musa is one of two or three genera in the family musaceae ; it includes bananas and plantains .

around 70 species of musa are known , with a broad variety of uses .

though they grow as high as trees , banana and plantain plants are not woody and their apparent " stem " is made up of the bases of the huge leaf stalks .

thus , they are technically gigantic herbs .

musa species are used as food plants by the larvae of some lepidoptera species , including the giant leopard moth and other hypercompe species , including h. albescens ( only recorded on musa ) , h. eridanus , and h. icasia .

musa ( genus )

sister relationship , the latter genus is well supported ( bpp , 0 . 98 ) . the genus
sectional relationships in the genus musa l . inferred from the pcr‐rflp of organelle dna sequences
1 . the nomenclature of the genus musa by david constatine . retrieved 5 july 2017 .
the genus musa is in the family musaceae in the major group angiosperms ( flowering plants ) .
sectional relationships in the genus musa l . inferred from the pcr - rflp of organelle dna sequences
almost all modern edible parthenocarpic bananas come from the two wild species musa acuminata and musa balbisiana . the scientific names of bananas are musa acuminata , musa balbisiana or hybrids musa acuminata × musa balbisiana , depending on their genomic constitution . the old scientific names musa sapientum and musa paradisiaca are no longer used .
musa is the name of the genus to which wild and cultivated bananas belong . in the hierarchy of botanicall classification , a genus comes above species and below family . in the binomial nomenclature system created by carl linneaus , the genus name forms the first part of the binomial species name for each species within the genus ( e . g . musa acuminata ) .
almost all modern edible parthenocarpic bananas come from the two wild species musa acuminata and musa balbisiana . the scientific names of bananas are musa acuminata , musa balbisiana or hybrids musa acuminata × balbisiana , depending on their genomic constitution . the old scientific names musa sapientum and musa paradisiaca are no longer used .
almost all modern edible parthenocarpic bananas come from the two wild species – musa acuminata and musa balbisiana . the scientific names of bananas are musa acuminata , musa balbisiana or hybrids musa acuminata × balbisiana , depending on their genomic constitution . the old scientific names musa sapientum and musa paradisiaca are no longer used .
almost all modern edible parthenocarpic bananas come from the two wild species – musa acuminata and musa balbisiana . the scientific names of bananas are musa acuminata , musa balbisiana or hybrids musa acuminata × balbisiana , depending on their genomic constitution . the old scientific names musa sapientum and musa paradisiaca are no longer used .
2 . cheesman , e . e . 1947 . classification of the bananas . i . the genus ensete horan and the genus musa l . kew bulletin ( 2 ) : 97 - 117 .
3 . cheesman , e . e . 1947 . classification of the bananas . i . the genus ensete horan and the genus musa l . kew bulletin ( 2 ) : 97 - 117 .
4 . cheesman , e . e . 1947 . classification of the bananas . i . the genus ensete horan and the genus musa l . . kew bulletin ( 2 ) : 97 - 117 .
the plant list includes 203 scientific plant names of species rank for the genus musa . of these 66 are accepted species names .
shepherd k . cytogenetics of the genus musa ( international network for the improvement of banana and plantain , montpellier ) . 1999 .
banana is also used to describe enset and fe ' i bananas , neither of which belong to the musa genus . enset bananas belong to the genus ensete while the taxonomy of fe ' i - type cultivars is uncertain .
banana is also used to describe enset and fe ' i bananas , neither of which belong to the musa genus . enset bananas belong to the genus ensete while the taxonomy of fe ' i - type cultivars is uncertain .
nwakanma dc , pillay m , okoli be , tenkouano a . sectional relationships in the genus
the genus musa is divided into two sections : musa and callimusa [ 1 ] . a section is a taxonomic rank below the genus , and subgenus if present , and above the species . it is also above the series , but in the case of bananas the term series has been used interchangeably with section . in 2013 , the number of sections in the genus musa was reduced from 5 to 2 [ 1 ] .
musapedia pages that mention cheesman : musa sections , nomenclature of cultivated bananas , calcutta 4 , musa itinerans .
a taxonomic genus within the family musaceae – large tropical herbs , commonly known as banana plants .
chessman also developed a coherent classification system for the musa genus , which he divided into four sections : australimusa , callimusa , eumusa and rhodochlamys [ 2 ] .
musa chunii häkkinen , a new species ( musaceae ) from yunnan , china and taxonomic identity of musa rub . . .
enter family names in full and use the wildcard character ( * ) for partial matches on genus and species .
1 . according to article 21 . 3 , the epithet in the name of a subdivision of a genus is not to be formed from the name of the genus to which it belongs by adding the prefix eu - . moreover , the name of any subdivision of a genus that includes the type of the adopted , legitimate name of the genus to which it is assigned is to repeat that generic name unaltered , according to article 22 . 1 .
there are 7 species in the genus ensete , all from tropical africa and asia . they were formerly placed in the banana genus , musa . in ethiopia , in addition to being an important food crop , it is also used in traditional medicine , and the leaves are used for thatching .
dill ( anethum graveolens ) is a short - lived perennial herb . it is the sole species of the genus anethum , though classified by some botanists in a related genus as peucedanum graveolens ( l . ) c . b . clarke .
the problems highlighted reveal the shortcomings of the current state of musa classification . hence , this study employs aflps in a phenetic examination of the relationships among sections musa , rhodochlamys , callimusa and australimusa of genus musa , and evaluates whether genetic differences among the sections are sufficiently significant or distinct to justify maintaining the four sections as separate groups .
shepherd k . 1990 . observations on musa taxonomy . in : jarret rl , ed . identification of genetic diversity in the genus musa : proceedings of an international workshop held at los banos , philippines , 5–10 september 1988 . france : inibap , montferrier‐sur‐lez , 158–165 .
tezenas du montcel h ( 1988 ) musa acuminata subspecies banksii : status and diversity . in : identification of genetic diversity in the genus musa . proc int workshop , los banos , philippines 5 - 10 september 1988 . inibap , montpellier , france , pp : 211–218 .
, a single colonization event from northern indo‐burma gave rise to the african species of the genus . at the time of divergence of
( a ) musa yunnanensis ( itc . 1573 ) ; ( b ) musa mannii ( itc . 1574 ) ; ( c ) musa rosea x siamensis ( itc . 1592 ) ; ( d ) musa campestris var . sarawakensis ( itc . 1517 ) ; ( e ) musa monticola ( itc . 1528 ) ; ( f ) musa lutea ( itc . 1515 ) . chromosomes were counterstained with dapi . bar = 5 μm .
a section is a taxonomic rank below the genus and above the species . it’s typically used to highlight relationships within a genus . for bananas , the first attempt to tidy up the musa genus dates back to 1887 , when the french botanist paul sagot recognized three groups : edible bananas , ornamental bananas with upright inflorescences and brightly coloured bracts , and giant enset species , which have since been given their own genus . sagot did not give names to his sections , but a few years later the british botanist john g . baker classified them as subgenera and respectively named them eumusa , rhodochlamys and physocaulis .
banana is the common name for herbaceous plants of the genus musa and for the fruit they produce . bananas come in a variety of sizes and colors when ripe , including yellow , purple , and red .
taxonomy , it is challenging to infer the exact number of species within the genus . based on the study of häkkinen & väre (
typification and check‐list of musa l . species names ( musaceae ) with nomenclatural notes
over the years several authors based the taxonomy of bananas on musa paradisiaca and musa sapientum . sometimes musa sapientum was treated as a subspecies of musa paradisiaca , but at other times botanical priority was ignored and musa paradisiaca was treated as a subspecies of musa sapientum . moreover , since musa paradisiaca is seedless , the subspecies seminifera was created in order to accommodate the wild seeded forms . giving a seed - bearing wild species the status of subspecies to a seedless cultivar is a good example of the stultifying effect formal nomenclature has had on the crop ' s taxonomy .
agrobacterium - mediated transformation of musa acuminata cv . ‘grand nain’ scalps by vacuum infiltration
figure 3 . the erect bunch of musa maclayi a wild australimusa banana species .
researchers norman simmonds and ken shepherd proposed the genome - based nomenclature system in 1955 . this system eliminated almost all the difficulties and inconsistencies of the nomenclature system of bananas based on musa sapientum and musa paradisiaca . despite this , musa paradisiaca is still recognized by some authorities today , leading to confusion . generally , modern classifications of banana cultivars follow simmonds’ and shepherd’s system . the accepted names for bananas are musa acuminata , musa balbisiana or musa acuminata × balbisiana , depending on their genetic ancestry
molecular analysis and genomic organization of major dna satellites in banana ( musa spp . )
factors influencing seed set in triploid musa spp . l . and production of euploid hybrids
figures 7 and 8 . the wild giant banana of montane forests , musa ingens .
relationship between nuclear 2c dna content and 2n chromosome number in representatives of the genus musa studied in the present work ( empty circles ) and by bartoš et al . [ 9 ] ( full circles ) , r = - 0 . 85 .
shepherd k ( 1988 ) observation on mus a taxonomy . in : identification of genetic diversity in the genus musa . proc int workshop held at los banos , philippines 5 - 10 september 1988 . inibap : montpellier , france , pp 158–165 .
daniells , j . , jenny , d . , karamura , d . and tomekpe , k . ( 2001 ) musalogue : a catalogue of musa germplasm . diversity in the genus musa . ( e . arnaud and s . sharrock , compil . ) . international network for the improvement of banana and plantain , montpellier , france .
in 1887 , the french botanist paul sagot published an article in which he subdivided the genus into three unnamed sections : i ) the edible bananas , ii ) the ornemental bananas with upright inflorescences and brightly coloured bracts , and iii ) the giant enset species , which were later given their own genus [ 2 ] .
isolation , characterization and chromosome localization of repetitive dna sequences in bananas ( musa spp . )
isolation , characterization and chromosome localization of repetitive dna sequences in banana ( musa spp . )
in view of the importance of chromosome numbers in grouping species within the genus musa , it will be of great interest to carry out a molecular study on the sole member of sect . ingentimusa that has a chromosome number of n = x = 14 .
started during the late eocene ( mean age estimate , 37 . 9 ma ; 50 . 5–24 . 5 ma 95 % hpd ) . clade i in the genus
the majority of dessert bananas eaten today derive from musa acuminata and are mainly eaten raw . plantains which are more starchy and less sweet are a hybrid between musa acuminata and musa balbisiana are usually cooked and eaten as a vegetable . morphologically wild banana is very different to its cultivar .
the species that currently make up each section are listed in the musapedia page on musa sections .
musa x fennicae ( m . siamensis ( male ) x m . rosea ( female ) )
musa x fennicae ( m . siamensis ( male ) x m . rosea ( female ) )
flow cytometric estimation of nuclear dna amount in diploid bananas ( musa acuminata and m . balbisiana )
comparative analysis of phenotypic and genotypic diversity among plantain landraces ( musa spp . , aab group )
flow cytometric estimation of nuclear dna amount in diploid bananas ( musa acuminata and m . balbisiana )
before simmonds and shepherd ' s system , cultivated bananas were classified using the binomial nomenclature system developed by carl linneaus that is used to this day to name species . in fact linneaus is the one who gave the name musa paradisiaca to the banana . being the first linnean name given to a banana , musa paradisiaca is technically the
type species
for the genus musa . except that musa paradisiaca , and musa sapientum which linnaeus later added to the genus , had been modeled after a plantain and a silk cultivar , respectively , and as such did not represent species in any reasonable sense of the word . nevertheless , these names , and others that were proposed in their wake , continue to be used to designate cultivars despite the existence of the nomenclature system developed by simmonds and shepherd ( see previous section ) .
the plant list includes a further 181 scientific plant names of infraspecific rank for the genus musa . we do not intend the plant list to be complete for names of infraspecific rank . these are primarily included because names of species rank are synonyms of accepted infraspecific names .
visit my website at urltoken - bananas are produced by several kinds of large flowering plants in the genus musa . the banana plant itself is considered to be the largest herbaceous flowering plant . because the plants are tall and fairly sturdy , they are often mistaken for trees .
this study improves significantly the knowledge about the nuclear genome of wild musa species . we provide novel data on nuclear genome size and genomic distribution of ribosomal genes in 21 wild musa accessions . we revealed high variability in both characters , especially in the section callimusa . our results indicate that species of the musa genus evolved from a common ancestor by chromosome fission , which was accompanied by dna loss . cladogram based on the ssr markers together with the previously studied wild diploids showed clear clustering and significantly increased the knowledge on genetic diversity within musa genus . ssr genotyping platform enabled us to identify groups of the most related species and sub - species . apart from phylogenetic analysis , characterization of its sequences indicated that more than a half of the new itc accessions representing wild musa accessions originated from hybridization between different genotypes within a species or between putative subspecies .
all three musaceae genera – ensete , musa and musella – originated in northern indo‐burma during the early eocene . musa species dispersed from ‘northwest to southeast’ into southeast asia with only few back‐dispersals towards northern indo‐burma .
at the time of the revision , the musa section included 33 species and the callimusa one 37 .
musa genotyping centre was established at the institute of experimental botany in olomouc , czech republic . available :
] in accordance to their expected classification based on plant morphology . newly introduced accessions belonging to the musa section were grouped within the cluster a comprising other species from section musa . the two accessions described as
musa × paradisiaca l . subsp . sapientum ( l . ) c . e . o . kuntze
li , l . - f . et al . 2010 . molecular phylogeny and systematics of the banana family ( musaceae ) inferred from multiple nuclear and chloroplast dna fragments , with a special reference to the genus musa . molec . phylogenet . evol . 57 : 1 - 10 .
about 40 species of evergreen perennials make up this genus from india , bangladesh , asia , and australia . they are grown for their very large leaves , their colorful flowers , and their edible fruits ( including bananas and plantains ) . use musa as specimens or in a greenhouse .
structures of waxy and adh 1 genes in musa and the positions of each primer used in this study .
identification of the genomic constitution of musa l . lines ( bananas , plantains and hybrids ) using molecular cytogenetics
de langhe , e . et al . 2005 . integrating morphological and molecular taxonomy in musa : the african plantains ( musa spp . aab group ) . pl . syst . evol . 255 : 225 - 236 .
12 . musa sections revisited published 28 august 2013 in under the peel , the blog of the promusa community .
musa genotyping centre was established at the institute of experimental botany in olomouc , czech republic . available : urltoken .
banana is also used to describe enset and fe’i bananas , neither of which belong to the aforementioned species . enset bananas belong to the genus ensete while the taxonomy of fe’i - type cultivars is uncertain .
phylogeny of banana streak virus reveals recent and repetitive endogenization in the genome of its banana host ( musa sp . )
the system is based on 15 characters that were chosen because they are different in musa acuminata and musa balbisiana [ 1 ] . each character is scored on a scale from one ( typical musa acuminata ) to five ( typical musa balbisiana ) . the possible total scores range from a minimum of 15 to a maximum of 75 . the expected scores are 15 for aa and aaa , 35 for aab , 45 for ab , 55 for abb and 75 for bb .
aflp has provided important information regarding the genetic relationships among taxa of sections of musa . in addition , it has generated unique molecular markers for the identification of musa species . the level of polymorphism in musa and the number of loci generated per primer pair using aflp compare favourably with other techniques . a study employing issrs in musa ( godwin et al . , 1997 ) generated 940 bands from ten primer pairs , but only 13·1 % were polymorphic , while rflp analysis of musa ( gawel et al . , 1992 ) using 66 primers generated only 96 alleles , an average of two alleles per probe .
comparative analysis of argonaute gene sequences in bananas ( musa sp . ) shows conserved species - specific ago - 7 piwi domains
as ernest cheesman noted in 1948 ,
some botanists have regarded the seedless forms as ranking with the fertile species and have bestowed latin binomials upon them . others have preferred to regard them as varieties of one mythical “ species” ( usually called musa sapientum ) which is supposed to exist somewhere in the wild and fertile condition … such mistakes . . . are not peculiar to the genus musa , but they are unusually conspicuous in this group
[ 3 ] .
species in one of the two distinct tropical southeast asian subregions ( northern indo‐burma vs malesia ) is correlated with changes in extinction and speciation rate within that genus . of the eight models tested , the bisse‐bma analysis in b
results of aflp analysis showed that the 11‐chromosome and 10‐chromosome grouping are robust and justified and that the separation of musa species into different groups based on their chromosome numbers provides a reliable means for classifying musa species into sections . in contrast , the separations of sect . rhodochlamys from sect . musa , and sect . australimusa from sect . callimusa were not supported by the aflp analysis . indeed , there is more genetic variation within the two groupings , sect . musa – rhodochlamys and callimusa – australimusa , than there is between sect . musa and sect . rhodochlamys and between sect . callimusa and sect . australimusa , drawing attention to the fact that striking differences in morphological characters in musa species are not always indicative of the same degree of genetic difference .
most of the knowledge on nuclear genome size and genomic distribution of rdna loci in banana comes from the analysis of triploid cultivars and their wild ancestors [ 14 – 16 , 17 , 18 , 46 ] . only the study of bartoš et al . [ 9 ] included a wider range of musa species and provided the first complex picture of the whole genus . our study significantly expands the number of wild musa species where these key characteristics of nuclear genome are described .
ball t , vrydaghs l , van den hauwe i , manwaring j , and de langhe e . 2006 . differentiating banana phytoliths : wild and edible musa acuminata and musa balbisiana . journal of archaeological science 33 ( 9 ) : 1228 - 1236 .
fig . 2 . dendrogram showing genetic similarities between species of musa and ensete using upgma cluster analysis . scale bar depicts gdes .
phylogeny of banana streak virus reveals recent and repetitive endogenization in the genome of its banana host ( musa sp . ) | springerlink
secondary polyploids , heterosis , and evolutionary crop breeding for further improvement of the plantain and banana ( musa spp . l ) genome
analysis of expressed sequence tags from musa acuminata ssp . burmannicoides , var . calcutta 4 ( aa ) leaves submitted to temperature stresses
musa × paradisiaca var . dacca ( p . f . horaninow ) j . g . baker ex k . m . schumann
for the banana cultivar previously referred to as musa sapientum , see latundan banana . [ 19 ] for bananas and plantains previously referred to as musa paradisiaca , see plantain . for a list of the cultivars classified under the new system see banana cultivar groups .
figures 12 and 13 . wild australimusa banana species , musa maclayi growing in sheltered gully and bunches showing differences in bract retention .
overview : there is a huge amount of morphological variability in the cultivated banana . musa spp . which include banana and plantain , are not trees but giant herbs with a pseudostem ( formed from the bases of leaves rolled tightly around each other ) . members of this genus can grow up to 15 m tall making them the largest perennial herb in the world .
based on phenetic analyses , no clear distinction was apparent between species of sect . rhodochlamys and those of sect . musa . m . velutina ( sect . rhodochlamys ) was embedded within species of sect . musa , and m . laterita ( sect . rhodochlamys ) nestled within subspecies of m . acuminata . musa ornata ( sect . rhodochlamys ) also fell within the generally larger cluster of sect . musa . these results suggested that sect . rhodochlamys and sect . musa are not sufficiently distinct genetically to warrant separation into two sections . this is in agreement with the conclusions of simmonds ( 1962 ) , shepherd ( 1990 ) and jarret and gawel ( 1995 ) .
häkkinen , m . 2013 . reappraisal of sectional taxonomy in musa ( musaceae ) . ( taxon ) 62 : 809 - 813 .
musa flowers are individually not conspicuous , but the large main bracts are quite conspicuous ; the bracts curl back in turn to expose the flowers they have protected while in bud . musa species ( including cultivated bananas ) with pendulous inflorescences and dull purplish bracts have flowers with…
the species in the old eumusa section were described by cheesman as being more than 3 meters high , having pendent or semi - pendent inflorescences , many flowers to a bract and dull - coloured bracts . the section includes musa acuminata and musa balbisiana ( photo ) .
pcr - rflp of the ribosomal dna internal transcribed spacers ( its ) provides markers for the a and b genomes in musa l .
bananas are basically giant herbs , rather than trees , and there are approximately 50 species in the musa genus , which includes the edible forms of bananas and plantains . the genus is split into four or five sections , based on the number of chromosomes in the plant , and the region where they are found . furthermore , over a thousand different types of cultivars of bananas and plantains are recognized today . the different varieties are characterized by wide differences in peel color and thickness , flavor , fruit size , and resistance to disease . the bright yellow one found most frequently in western markets is called the cavendish .
the first subgeneric classification of musa s . l . began with three subgenera physocaulis , eumusa and rhodochlamys ( sagot , 1887 ; baker , 1893 ) . later , cheesman ( 1947 ) laid the foundation for the grouping of banana species into four sections . he recognized subgenus physocaulis as a distinct genus , ensete with a chromosome number n = x = 9 . within musa s . s . , he redefined subgenera eumusa ( now sect . musa ) and rhodochlamys as two separate sections , and described an additional two sections , australimusa and callimusa . cheesman ( 1947 ) also redistributed the species among the four sections to produce more homogenous groups .
in addition to m . acuminata and m . balbisiana , the genus musa contains about 70 species . based on morphology [ 5 ] and chromosome number , the genus was divided into sections eumusa ( x = 11 ) , rhodochlamys ( x = 11 ) , australimusa ( x = 10 ) and callimusa ( x = 9 , 10 ) [ 6 ] . more recently , argent [ 7 ] created a separate section ingentimusa , which contains only a single species m . ingens ( x = 7 ) . this classification has been questioned recently , and various regroupings were suggested [ 8 ] . genotyping with several types of dna markers confirmed the need for revision of the musa sections [ 9 – 12 ] . based on these results , häkkinen [ 13 ] combined the australimusa , ingentimusa and callimusa sections into section callimusa , and sections eumusa and rhodochlamys into a newly created section musa .
the taxonomy of the approximately 50 species within the genus musa remains poorly resolved , not least because of the widespread vegetative reproduction and natural occurrence of many hybrids . most frequently , the genus is divided into four ( sometimes five ) sections , eumusa and rhodochlamys with a basic chromosome number of x = 11 , australimusa ( x = 10 ) , and callimusa ( x = 10 or x = 9 ) ( after cheesman , 1947 ; simmonds and weatherup , 1990 ; dolezel and bartos , 2005 ) . various minor and major regroupings have been suggested ( wong et al . , 2002 ) . at the species level , the number of species and the status of subspecies has been debated ( taxonomic advisory group for musa , 2007 ) . however , from the point of view of the taxa related to crops , the morphological features are well defined ( musa germplasm information system , mgis ; ipgri–inibap / cirad , 1996 ) . in the last decade , in conjunction with molecular studies of musa accessions at the dna level ( see bartos et al . , 2005 ) , aspects of the taxonomy have been clarified but a careful treatment of the complementary and contrasting data , along with judicious filling of gaps in the data , is required to resolve the relationships and phylogeny in the genus .
cheesman ( 1947 ) noted that sect . musa and sect . rhodochlamys , although regarded as a close assemblage , were initially separated for convenience , sect . musa including the edible bananas with dull bracts while sect . rhodochlamys included the ornamental bananas with brightly coloured bracts . this view is no longer tenable in the face of genetic evidence and these two sections should be merged into a single section , sect . musa .
13 . lamare , a . , otaghvari , a . m . and rao , s . r . 2016 . phylogenetic implications of the internal transcribed spacers of nrdna and chloroplast dna fragments of musa in deciphering the ambiguities related to the sectional classification of the genus . genetic resources and crop evolution , 11 pages . doi : 10 . 1007 / s10722 - 016 - 0433 - 9 .
genome groups are further divided into subgroups usually defined as a set of cultivars derived from each other through somatic mutations . on the basis of this system , cultivar names are put between inverted commas and preceded by the name of the genus and when known , the name of the group and subgroup . for example : musa ( aaa group cavendish subgroup ) ' robusta ' [ 2 ] .
in 1976 , george argent added the section , ingentimusa for the lone species musa ingens , which has 7 pairs of chromosomes [ 5 ] .
molecular cytogenetics of musa species , cultivars and hybrids : location of 18s - 5 . 8s - 25s and 5s rdna and telomere - like sequences
centrifugation assisted agrobacterium tumefaciens - mediated transformation ( caat ) of embryogenic cell suspensions of banana ( musa spp . cavendish aaa and lady finger aab )
construction and characterization of a plant transformation - competent bibac library of the black sigatoka - resistant banana musa acuminata cv . tuu gia ( aa )
figure 14 . articulated phytoliths from seed of musa acuminata ssp . banksii qh067962 showing distinct dorsal ridging of eumusa seed phytoliths . b : articulated phytoliths from seed of musa peekelii lh82751 with distinctive tabular dorsal surfaces found in australimusa seed phytoliths . these were not found in the kuk assemblages . c : seed phytolith from seed of musa ingens . d : dorsal and lateral views of ensete glaucum seed phytoliths qh356652 . e : fossil eumusa seed phytolith with distinct dorsal ridging found in the phytolith assemblage from kuk . f : facetted phytolith seed morphotype of musa ingens found in the phytolith assemblage from kuk . lateral view of ensete seed morphotype found sediment from kuk . h : articulated chain of musa leaf phytoliths found in sediment from kuk .
8 . li , l - f . , häkkinen , m . , yuan , y - m . , hao , g . and ge , x . j . 2010 . molecular phylogeny and systematics of the banana family ( musaceae ) inferred from multiple nuclear and chloroplast dna fragments , with a special reference to the genus musa . molecular phylogenetics and evolution 57 ( 1 ) : 1 - 10 .
1 . häkkinen , m . 2013 . reappraisal of sectional taxonomy in musa ( musaceae ) . taxon 62 ( 4 ) : 809 - 813 .
musa puspanjaliae r . gogoi & häkkinen , a new species of musa sect . musa , is described and illustrated from west kameng , arunachal pradesh , india based on morphological characteristics observed in the field . the new species is common in sessa , zero point to ramda on sepa road of west kameng and hazi basti , ziro of lower subansiri district in arunachal pradesh . a key to m . puspanjaliae and . . . [ show full abstract ]
genetic stability of three economically important micropropagated banana ( musa spp . ) cultivars of lower indo - gangetic plains , as assessed by rapd and issr markers
the apple is the pomaceous fruit of the apple tree , species malus domestica in the rose family ( rosaceae ) . it is one of the most widely cultivated tree fruits , and the most widely known of the many members of genus malus that are used by humans .
the present work is part of a continuing study to revise the old names in musa and aims to clarify the taxonomy in the sections rhodoclamys and callimusa . lectotypes are designated here for musa sect . callimusa and m . sect . rhodochlamys . these sections were first erected without the indication of a type species .
in a broader phylogenetic view based on groupings that can be regarded as strictly monophyletic , angiosperm phylogeny group ( 2003 ) puts musa within the zingiberales , one of four sister orders in the monophyletic grouping commelinids , along with the poales ( grasses ) , commelinales and aracales . this puts musa in an important taxonomic position from the point of view of comparative genetics , since it is a sister group to the well - studied grasses . apart from the cereals , bananas are the major crop species within the commelinids . the musaceae family includes a second genus , ensete , with the ethiopian banana , used occasionally as a food in east africa . ginger , where the root is eaten , is the other significant crop in the zingiberales . there are a number of horticultural species in the genus musa , and strelitzia reginae ( bird - of - paradise ) lies in the sister familiy strelitziacea . the leaves of musa are used for their fibre content : when fresh as plates for eating or wrapping food parcels for steaming , or when dry as strips for weaving into various articles and for roofing shelters . specific names such as m . ornata and m . textilis reflect these uses .
the center of diversity of the genus musa ( musaceae ) is in southeast asia , a region not studied in detail and where new species and varieties continue to be reported . a new wild banana species , m . chunii häkki - nen from yunnan , china is described and illustrated based on observed morphological characteristics in the field . this extremely rare new species was only found in tongbiguan nature . . . [ show full abstract ]
the plant is also called head cabbage or heading cabbage , and in scotland a bowkail , from its rounded shape . the scots call its stalk a castock , and the british occasionally call its head a loaf . it is in the same genus as the turnip – brassica rapa .
this article examines the origin and evolution of the musaceae family with special emphasis on the tempo and timing of diversification of the genus musa in relation to its distribution range throughout tropical southeast asia . evolutionary relationships and age estimates within major musaceae clades are inferred to gain more insight into the complex processes of speciation and extinction that shaped the current banana biodiversity in tropical southeast asia . in addition , we discuss to what extent past climatic and geological events , such as the continuous sea level fluctuations during the pleistocene and the collision of the sunda and sahul shelf , influenced the radiation of musa in tropical southeast asia .
) . in a majority of accessions from the musa section , 5s rdna sites were localized on two or three chromosome pairs . three signals were observed on chromosomes of
bananas and plantains belong to the genus musa . it was linnaeus that first gave the scientific name musa sapientum for all sweet bananas , and the scientific name musa paradisiaca for plantains . however , linnaeus did not know that the two species he had described were in fact hybrids and not two distinct species . therefore , those two names could not be relevant in modern taxonomy . genetic studies have then demonstrated that all edible bananas and plantains come from a common ancestor , musa acuminata . plantains also carry genes from another ancestor , musa balbisiana . the genome of each ancestor could be represented respectively by the letter a and b . then , further studies showed that edible bananas are mostly triploids and their genome would be described as aaa . this means that they carry three sets of chromosomes derived from m . acuminata . different hybrid combinations have been observed , such as aab , bbb , and tetraploid groups ( aaaa ) were also described . therefore , an accurate classification for bananas seems to be a great challenge . however , one thing sure in that banana taxonomists seem to agree that there is no single scientific name that can be attributed to all edible bananas . therefore , a new type of classification was proposed by simmonds and that would abandon the latin name to use instead a group indication like this : genus ( musa ) + genome group ( e . g . aaa ) + subgroup name ( e . g . cavendish subgroup “grand nain” ) . in panama , the sweet bananas come mostly from the cavendish subgroup . the plantain subgroup is also triploid but has the genome group aab .
musa itinerans , known also as yunnan banana , is a close relative to both banana progenitors with wide distribution across subtropical china . it is native to south - east asia and can be found in moist ravines to mountainous areas . in china , it is usually found in secondary tropical rainforests . it grows fast and can produce long rhizome with sucker emerging more than 2 meters from the mother plant , explaining its name origin . interestingly , it was shown as one of the most foc - tr4 resistant and cold tolerant species in the musa genus , providing valuable resource for the disease resistance and hardiness improvement in banan . . . [ more ]
between 1925 and 1937 , cheesman worked as professor of botany at the imperial college of tropical agriculture in trinidad . after his return to england , he worked on the taxonomy of musaceae at the royal botanic gardens , in kew . as a result of his studies he revived the genus ensete [ 2 ] , first published in 1862 by paul fedorowitsch horaninow , but then not accepted . cheesman made it clear that there are no wild musa native to africa , only ensete .
by then , it was known that the vast majority of edible bananas were derived from either musa acuminata alone or hybridized with musa balbisiana . however , their origin proved to be more complicated than mere hybridisation . whereas some cultivars were , like their wild ancestors , diploid , most edible bananas were found to be triploid , that is they had three sets of chromosomes instead of two . in some cultivars all three sets seemed to come from musa acuminata , whereas in others , sometimes one set seemed to come from musa balbisiana , sometimes two sets . this complexity made it difficult to devise a concise nomenclature system based on latin names that could cope with all possible permutations [ 4 ] .
cultivated bananas are large , vegetatively - propagated members of the genus musa . more than 1 , 000 cultivars are grown worldwide and they are major economic and food resources in numerous developing countries . it has been suggested that cultivated bananas originated from the islands of southeast asia ( isea ) and have been developed through complex geodomestication pathways . however , the maternal and parental donors of most cultivars are unknown , and the pattern of nucleotide diversity in domesticated banana has not been fully resolved .
the taxon sampling represents five ensete species ( six accessions ) , 38 musa species ( 63 accessions ) and one species ( one accession ) of musella ( supporting information table s1 ) . in order to correctly estimate node ages for ensete , musa and musella , we extended the musaceae dataset with 156 zingiberales species and two outgroup taxa ( methods s1 ) .
hybridization is known to be common between species from sect . musa and sect . rhodochlamys , producing relatively vigorous offspring . according to simmonds ( 1962 ) , m . acuminata ( sect . musa ) crosses effectively with m . laterita , m . ornata and m . velutina ( all from sect . rhodochlamys ) , while m . balbisiana ( sect . musa ) hybridizes successfully with almost all species , including m . laterita and m . velutina . the weak reproductive barrier between the two sections supports the notion that they are not distinct .
an interesting outcome of this study is the observation of a negative correlation between the basic chromosome number ( x ) and nuclear genome size ( 1c ) , which became evident in this study after a wider range of musa species was analyzed . this trend could be explained by the evolution from a common ancestor by chromosome fission accompanied by dna loss . this hypothesis is in line with simmonds [ 49 ] , who speculated that the lower chromosome number of m . beccarii and the genus ensete reflects their ancient origin . similarly , bekele and shigeta [ 50 ] suggested that ensete glaucum and m . beccarii are ancestral forms of ensete and musa with a common ancestor that is yet to be established and the ancestral chromosomal number of both genera is x = 9 . on the other hand , if this hypothesis was true , representatives of the genera ensete and musella would be expected to have a genome size comparable to that of and other callimusa species . a more extensive study of the karyotype evolution in the family musaceae will be necessary to explain this
the less chromosomes , the larger genome
trend emerging in the genus musa , but not observed in other genera of the family .
( itc . 1531 ) ) . four groups comprised different representatives of the section musa ( former sections eumusa and rhodochlamys ) and two groups included different species belonging to section callimusa .
comparison of dna marker and pedigree - based methods of genetic analysis of plantain and banana ( musa spp . ) clones . i . estimation of genetic relationships , theoretical and applied genetics
. . . edible seedless bananas mostly grown in the backyards or home gardens whereas wild seeded bananas commonly found in the wild [ 4 ] . the genus musa are generally grouped into four sections : australimusa ( n = 10 ) , callimusa ( n = 10 ) , rhodochlamys ( n = 11 ) and eumusa ( n = 11 ) [ 5 , 6 , 7 , 8 ] . most members of callimusa and rhodoclamys are ornamentals in nature ; they originated on the asian continent . . . .
compared to other species discussed in this volume , banana has an unusual triploid genetic background with parthenocarpy , and the process of domestication has been largely through collection of individual varieties from spontaneous mutations in the wild . hence conventional genetics and plant breeding are relatively poorly developed . however , genomic approaches are now rapidly advancing in musa : the global musa genomics consortium was established in 2001 to assure the sustainability of banana as a staple food crop by developing an integrated genetic and genomic understanding , allowing targeted breeding , transformation and more efficient use of musa biodiversity .
previous studies in the fields of archaeology , genetics and linguistics have shed light upon the major stages in the domestication process of cultivated bananas [ 1 ] , [ 2 ] , [ 70 ] . in this study , we have not only confirmed the multiple intra - and inter - specific hybridization origins of cultivated banana , but also revealed that both diploid and triploid cultivars harbor high levels of nucleotide diversity . however , only a small number of musa accessions were investigated in this study , and it may therefore be insufficiently representative of the genus . it will be necessary to employ tens of nuclear genes and hundreds of musa accessions in future studies to further elucidate the domestication process undergone by cultivated banana .
carreel f . etude de la diversité génétique des bananiers ( genre musa ) à l ' aide des margueurs rflp , phd thesis , institut national agronomique , paris - grignon ; 1994 .
perrier , x . et al . 2011 . multidisciplinary perspectives on banana ( musa spp . ) domestication . proceedings of the national academy of sciences of the usa 108 ( 28 ) .
the nomenclature system used to classify banana cultivars was developed by norman simmonds and kenneth shepherd in 1955 [ 1 ] . it classifies cultivated bananas into genome groups , according to the relative contribution of their ancestral wild species , and into subgroups , sets of closely related cultivars . this system eliminates almost all the difficulties and inconsistencies of a taxonomy based on musa paradisiaca and musa sapientum .
in 1947 , ernest cheesman divided the genus into four sections based on chromosome numbers and morphological characteristics [ 4 ] . he wrote that he deliberately called the groups sections rather than subgenera
in an attempt to avoid the implication that they are of equal rank
. his grouping of species proved to be useful and was widely accepted .
cultivated bananas and plantains are giant herbaceous plants within the genus musa . they are both sterile and parthenocarpic so the fruit develops without seed . the cultivated hybrids and species are mostly triploid ( 2 n = 3 x = 33 ; a few are diploid or tetraploid ) , and most have been propagated from mutants found in the wild . with a production of 100 million tons annually , banana is a staple food across the asian , african and american tropics , with the 15 % that is exported being important to many economies .
then came ernest e . cheesman , the prescient british botanist who realized that the classification of banana cultivars needed a system different from the latin binomials used for wild species . in 1947 , he divided the genus musa into four sections based on the chromosome numbers and morphological characteristics of the species : those that have 11 pairs of chromosomes ( eumusa and rhodochlamys ) and those that have 10 pairs ( australimusa and callimusa ) . he said that he deliberately used the term section , rather than subgenus , to avoid the implication that the groups are of equal rank . in 1976 , another british botanist , george argent , added the section ingentimusa to accommodate a lone species , musa ingens , which has 7 pairs of chromosomes .
the distinct separation of the clusters comprising species with chromosome numbers n = x = 11 in sect . musa and rhodochlamys , and species with chromosome numbers n = x = 10 in sect . callimusa and australimusa , is in agreement with previous taxonomic alignment based on morphological data . cheesman ( 1947 ) noted that chromosomal differences between taxa of sect . callimusa – australimusa and sect . musa – rhodochlamys were correlated with many small differences in their habits and physiology , and regarded chromosome number as the best and safest criterion of relationships within musa . this study is in agreement with cheesman’s data and also the cytogenetic evidence of simmonds ( 1962 ) and shepherd ( 1990 ) and the more recent study on species in sections musa and rhodochlamys using rflp by jarret and gawel ( 1995 ) .
musa balbisiana was shown to be most distant in the present analysis . it is generally considered a distinct species ( cheesman , 1948 ; simmonds , 1962 ) and other molecular studies have demonstrated its position as a species isolated within sect . musa ( simmonds and weatherup , 1990 ; gawel and jarret , 1991 ; gawel et al . , 1992 ; jarret et al . , 1992 ) .
wong , c . et al . 2002 . assessment of the validity of the sections in musa ( musaceae ) using aflp . ann . bot . ( oxford ) 90 : 231 - 238 .
the musa orthologs of the waxy and adh 1 genes were identified by performing a blast homology search [ 26 ] against the musa est database at ncbi using the oryza sativa coding sequences as queries ( genbank accession numbers : waxy : nm _ 001065985 , adh 1 : ef122490 ) . the parameters for blastn ( urltoken ) were set as follows : database was expressed sequence tags ( est ) and organism name was musa . sequences that were retrieved in this way were used to design primers with the software primer premier 5 . 0 ( premier biosoft international , palo alto , ca ) . the positions of exons were determined by reference to the annotated o . sativa sequences . the homologs of matk and trnl - f in musa accessions were amplified using published universal primer sequences [ 27 ] , [ 28 ] .
häkkinen , m . & väre , h . ( 2008 ) . typification and check - list of musa l . names ( musaceae ) with nomenclatural notes adansonia , iii , 30 : 63 - 112 .
the species in the old rhodochlamys section were described by cheesman as being less than 3 meters high , having upright inflorescences , few flowers to a bract and brightly coloured bracts . ( photo : musa velutina )
donohue m , and denham t . 2009 . banana ( musa spp . ) domestication in the asia - pacific region : linguistic and archaeobotanical perspectives . ethnobotany research & applications 7 : 293 - 332 . open access
within the rhodochlamys and musa clusters , m . balbisiana colla formed a distinct branch , while the remaining species in the cluster were separated into two groups . the first cluster included m . ornata roxb . , the four subspecies of m . acuminata colla , m . laterita cheesman , m . velutina h . wendl & drude and m . sikkimensis , while the second cluster included m . itinerans and m . nagensium prain . species from sect . rhodochlamys , m . ornata , m . laterita and m . velutina were embedded within sect . musa , suggesting that the separation of sect . rhodochlamys from sect . musa was not clear‐cut .


non-reproductive sexual behavior is sexual activities animals participate in that do not lead to the reproduction of the species .

although procreation continues to be the primary explanation for sexual behavior in animals , recent observations on animal behavior has given alternative reasons for the engagement in sexual activities by animals .

animals have been observed to engage in sex for social interaction , demonstration of dominance , aggression relief , exchange for significant materials , and sexual stimulation .

observed non-procreative sexual activities include non-copulatory mounting ( without penetration , or by the female ) , oral sex , genital stimulation , anal stimulation , interspecies mating , and acts of affection .

there have also been observations of animals engaging in homosexual behaviors , as well as sex with dead animals and sex involving juveniles .

non - reproductive sexual behavior in animals

why have animals evolved to have sex ? the obvious answer ,
for reproduction
, is at odds with the diversity of non - reproductive sexual behavior . some non - reproductive sexual behavior may exist merely by accident , but there ' s a variety of ways non - reproductive sexual behavior may otherwise benefit animals . there ' s no ready answer to the general question of why animals have sex .
ram mating behavior after long - term selection for reproductive rate in rambouillet ewes .
research on masturbatory practice by non - human animals almost exclusively focuses on male masturbation .
sexual behavior is an extremely significant aspect of the lives of all sexually reproductive animals , including humans . masturbation is an enigmatic yet highly ubiquitous practice , as it is a non - reproductive sexual behavior . understanding the origins of masturbation may shed light on its evolutionary function and its consequent conservation in human behavior , elucidating possible explanations for some of our most primal innate behaviors .
are used strictly in the reproductive sense to refer to animals that produce sperm or eggs , respectively ) .
why has natural selection allowed sexual affect and sexual behavior to flourish , particularly in humans ? the obvious answer is that sexual affect motivates sexual behavior , and sexual behavior is necessary for reproduction . but only a small subset of sexual behavior is actually capable of producing offspring . why has evolution preserved such things as masturbation , oral sex , homosexuality , and sex after menopause ?
regarding genetic influences on behavior : a single gene usually codes for complex behavior .
relationship of sex and number of siblings in utero with sexual behavior of mature rams .
in rats , a _ _ _ _ _ _ will display male sexual behavior in adulthood .
] . female animals treated with testosterone prenatally or neonatally subsequently show increased male - typical behavior and decreased female - typical behavior . similarly , male animals that have their testes removed early in development later show increased female - typical behavior and reduced male - typical behavior . these effects have been seen for sexual behaviors and for non - reproductive behaviors that differ by sex , such as aggression and juvenile rough - and - tumble play [
the most parsimonious explanation is that non - reproductive sexual behavior is a spandrel . that is , natural selection created a motivation to seek genital stimulation because this motivation makes animals more likely to reproduce , and it is merely an accident of evolution that this motivation also gets animals to do useless things like masturbate .
though most empirical research on the subject is heavily biased toward western sexual behavior .
a . expressing whether the behavior conforms to our culture ' s sexual norms .
altered adult sexual behavior in the male rat following chronic prenatal hypoxia . - pubmed - ncbi
wallen k , tannenbaum pl . hormonal modulation of sexual behavior and affiliation in rhesus monkeys .
stoinski ts , perdue bm , legg am . sexual behavior in female western lowland gorillas (
dolphins are known to display non - reproductive sexual behavior , engaging in masturbation , stimulation of the genital area of other individuals using the rostrum or flippers , and homosexual contact . [ 48 ] [ 53 ] [ 54 ]
gordon t ( 1981 ) reproductive behavior in the rhesus monkeys : social and endocrine variables . am zool 21 : 185–195
which of the following phrases best defines sexual variations ? a . sexual activity that involves force or coercion b . sexual behaviors that are not socially approved c . sexual behavior that is not statistically typical d . sexual expression that is illegal
by separating capability from interest , sexual behavior became more sensitive to social context , and sex could easily be used for other than reproductive purposes . once the capacity to engage in sex was released from hormonal control , hormonal modulation of sexual motivation became the primary regulator of sexual behavior . however , unlike the physical adaptations described earlier , which completely prevent the occurrence of sexual behavior , hormonal regulation of sexual motivation only modulates the frequency or likelihood of occurrence of sexual behavior . this less strict control exerted by sexual motivation has been the source of much misunderstanding about hormonal regulation of sexual behavior in primates , including humans .
wallen k . desire and ability : hormones and the regulation of female sexual - behavior .
) : insights into pseudogene formation and evidence for functional degeneracy in non - human primates .
homosexuality is quite common in the animal kingdom , especially among herding animals . many animals solve conflicts by practicing same gender sex .
the coverage of # savebenjy opens a dialogue on homosexual activity in a landscape that survives and thrives on heterosexual reproductive non - human animal activity in a male - dominated landscape .
autoeroticism is a . sexual fantasy . b . sexual behavior with others . c . an intrapersonal activity . d . an unacceptable activity .
the utility of nature as a heteronormatizing force was influenced by two factors . the first was industrialization , which moved people away from nature and interactions with other animals . the second factor was that aspect of darwin’s theory that emphasized animals’ drive to reproduce and continue the species . this emphasis on heterosexual reproductive activity created a picture of the non - human animal as only engaging in sexual activity with the opposite sex , and inevitably has led to under - recording or - documenting of same - sex behavior in non - human animals .
diurnal , larger than nwp , most are partly terrestrial . non - prehensile tails
a female rate will show female sexual behavior in adulthood if it is _ _ _ _ _ _ .
le boeuf b , mesnick s . sexual - behavior of male northern elephant seals . i .
in his book , bagemihl describes homosexual activity in a broad spectrum of animals . he asserts that while same - sex behavior is sometimes found in captivity , it is actually seen more frequently in studies of animals in the wild .
you can view the lecture here . at about the 11 : 40 point the claim is made that humans are the only species that engage in non - reproductive sex .
intracerebral infusion of an aromatase inhibitor , sexual behavior and brain estrogen receptor - like immunoreactivity in intact male rats .
wallen k , winston la . social complexity and hormonal influences on sexual behavior in rhesus monkeys ( macaca mulatta )
dittmann rw , kappes me , kappes mh . sexual behavior in adolescent and adult females with congenital adrenal hyperplasia .
effect of vorozole , an aromatase enzyme inhibitor , on sexual behavior , aromatase activity and neural immunoreactivity .
wallen k . influence of female hormonal state on rhesus sexual behavior varies with space for social interaction .
according to the text , when we label a sexual behavior natural or unnatural , we are a . expressing whether the behavior conforms to our culture ' s sexual norms . b . expressing instinctive beliefs . c . using biological criteria for our judgment . d . using universal norms for human sexual behavior .
many acts that are considered to be sex crimes involve parties who participate in such acts willingly . these crimes relate to issues of marriage and infidelity , non - reproductive sexual activities , prostitution and pandering , and pornography and obscenity .
bruce bagemihl argues that any evidence of non - reproductive same - sex activity has been rationalized , in effect “explaining away” ( 122 ) any same - sex behaviors . published in 1999 , bagemihl’s biological exuberance offers both a “wondrous bestiary” ( 265 ) chronicling the myriad of same - sex activities exhibited by a wide range of species , and an exploration of how non - reproductive homosexual activity in non - human animals is treated in scientific discourse . the # savebenjy campaign was treated as an oddity , but bagemihl demonstrates that homosexuality in animals is not a new phenomenon . he finds that homosexual activity exhibited by non - human animals , unless it is explicit sexual intercourse , is either omitted from research findings or insufficiently documented , being wrongly categorized under a number of other behaviors such as affiliation or dominance ( 107 ) .
although no mark and recapture techniques were applied in the present study , the seasonal distribution of svls suggests that animals were sexually mature in the first reproductive season after hatching .
i ' ve heard this about many species , including aforementioned bonobos , dolphins and more . also homosexual behavior in animals is rather widespread , and i ' ll be damned if that ' s a reproductive sex .
madsen t , shine r ( 1993 ) temporal variability in sexual selection acting on reproductive tactics and body size in male snakes . american naturalist 141 : 167–171 .
the thing that particularly fascinated me about this book was the broad array of variations in physical gender found in animals . for many animals ( e . g .
) . i . specimens , procedures and behavioral characteristics of estrus ii . periodicity of estrus , homosexual , autoerotic , and non - conformist behavior .
furuichi t , connor r , hashimoto c . non - conceptive sexual interactions in monkeys , apes , and dolphins in : yamagiwa j , karczmarski l . , editors .
the masters and johnson ' s model of sexual response does not account for the physical changes that occur in the clitoris . role of desire in sexual arousal . physiological components of sexual arousal . role of the autonomic nervous system in sexual response .
the vehemence with which this prohibition [ against sex with other species ] continues to be held , its persistence while other non - reproductive sexual acts have become acceptable , suggests that there is [ a ] powerful force at work : our desire to differentiate ourselves , erotically and in every other way , from animals .
sdn - poa volume , sexual behavior , and partner preference of male rats affected by perinatal treatment with atd .
zhao qk ( 1993 ) sexual behavior of tibetan macaques at mt . emei , china . primates 34 : 431–444
while in adult females the relationship between circulating hormone levels and sexual behavior varies with social context , adolescent females could show one of two patterns . adolescent females may show a tight coupling of hormones and behavior in which adult flexibility in response to social context develops during puberty . alternatively , adolescent females may have a loose coupling between circulating hormones and sexual behavior in which social context overrides increased sexual motivation in response to circulating hormone levels . we investigated variability among adolescent females in the relationship between sexual behavior and circulating hormone levels to address these two alternatives .
seth genuinely cares about his animals , yet he derives sexual pleasure from having sexual contact with them . seth is practicing a . klismaphilia b . bestiality c . zoophilia d . kennelism
tan et al . ( 2009 ) observed female greater short - nosed fruit bats ( cynopterus sphinx ) licking the shaft and base of their mate ' s penis during coitus . ( so unlike the other non - reproductive sexual behaviors discussed in this chapter , this behavior occurs only in an apparently reproductive context . ) tan et al . make a similar suggestion : saliva may kill pathogens and thus reduce the spread of disease .
influence of castration and estrogen replacement on sexual behavior of female - oriented , male - oriented , and asexual rams .
bercovitch fb , strum sc . dominance rank , resource availability , and reproductive maturation in female savanna baboons .
plenty of academic research referenced in detail at the wikipedia article on homosexual behavior in animals . roughgarden and bagemihl have done extensive research . urltoken urltoken urltoken urltoken urltoken urltoken
vasey pl . same - sex sexual partner preference in hormonally and neurologically unmanipulated animals . ann rev sex res . 2002 ; 13 : 141–79 .
ciaccio la , lisk rd , reuter la . prelordotic behavior in the hamster : a hormonally modulated transition from aggression to sexual receptivity .
goy , r . w . ( 1979 ) . sexual compatibility in rhesus monkeys : predicting sexual performance of oppositely sexed pairs of adults . in
) : androgens and behavior in a confined troop . horm behav 20 : 452–462
such studies have nonetheless observed autoerotic behavior in a diverse array of mammalian species .
there * have * been studies done on the reproductive success of homosexually paired birds . . .
bailey nw , zuk m . same - sex sexual behavior and evolution . trends in ecology and evolution . 2009 ; 24 : 439–46 .
taken together , these results suggest that in early adolescence , periovulatory increases in circulating estradiol increase female sexual initiation and female sexual motivation , as they do in adult females . in addition , these results suggest that social context can suppress female sexual behavior in early adolescent females , with one middle ranked female showing no sexual initiation at midcycle . in contrast , high social rank allows an uncoupling of circulating hormone levels and female sexual initiation behavior , since a high ranked female initiated interactions with males in the absence of periovulatory hormone levels .
benjy’s behavior challenged cultural perceptions of non - human animals as intrinsically heterosexual . his homosexual activity eluded normative sexual categories of ordering which are defined , discrete , and biologically determined . more importantly , benjy was no longer a charolais bull who engaged in homosexual activity ; he became a symbol , a representative for the naturalness of homosexuality .
4 . alfred c . kinsey et al . sexual behavior in the human female , w . b . saunders company , philadelphia , 1953 .
as one example , bottlenose dolphins routinely engage in non - reproductive intercourse - this can be when females are not in estrus ( i can ' t locate the reference though ) , and there is also a lot of non - intercourse sexual behaviour between individuals , even between males ( mann , j . 2006 . sociosexual behaviour among indian ocean bottle - nose dolphins and the development of male - male bonds .
while social rank affects the timing of the expression of sexual behavior within an adult female’s ovarian cycle , it rarely completely suppresses female sexual behavior ( wallen , 1990 ) . finally , adult males respond differently to sexual initiation by early adolescent and adult females ( zehr , 2002 ) . the increased aggression and decreased mounting by males toward adolescents also limits adolescent sexual behavior and further illustrates the special social status that adolescent females have within the social group .
sexual dimorphism in the coloration of the first and second rows of ventral longitudinal scales in the abdomen is probably associated with sexual maturation in males , since juveniles and females always presented white scales . feltrim ( 2002 ) suggested that sexual dimorphism in coloration could represent a social sign and could play an important role in sexual recognition .
beirne , p . ( in press ) . on the sexual assault of animals : a sociological view . in a . creager and b . jordan ( eds . ) ,
“a brilliant and important exercise in exposing the limitations of received opinion . . . an exhaustively argued case that animals have multiple shades of sexual orientation . ”
studies of rhesus monkey behavioral endocrinology offer two different pictures of the role that hormones play in female sexual behavior . early studies of social groups of rhesus monkeys described discrete periods of sexual activity interspersed with longer periods of sexual inactivity ( carpenter , 1942 ) . in contrast , studies of male - female pairs of rhesus monkeys reported midcycle peaks in sexual behavior but some sexual activity throughout the female’s cycle ( goy , 1979 ; michael & zumpe , 1970 ) . these markedly different patterns of sexual activity reflected the hormonal emancipation of the ability to mate combined with a sensitivity of sexual behavior to social context . subsequent studies demonstrated that the amount of space ( wallen , 1982 ) and the presence of multiple females ( wallen & winston , 1984 ) affected the extent to which the female’s hormonal condition modulated the occurrence of sexual behavior .
many animals of the same sex touch each other in ways that are not overtly sexual ( they do not involve direct contact of the genitals ) but that do nevertheless haveclear sexual or erotic overtones . these are referred to as
huffman ma ( 1992 ) influence of female partner preference on potential reproductive outcome in japanese macaques . folia primatol 59 : 77–88
animals are those with two distinct sexes in which males always remain male and females always remain female .
so , if we bread animals specifically for fucking it is o . k . ?
meyer - bahlburg hfl , dolezal c , baker sw , new mi . sexual orientation in women with classical or non - classical congenital adrenal hyperplasia as a function of degree of prenatal androgen excess .
dittmann rw , kappes me , kappes mh . sexual behavior in adolescent and adult females with congenital adrenal hyperplasia . psychoneuroendocrinology . 1992 ; 17 : 153–70 .
a more widely known example of
prostitution
in animals is hunter and davis ' s ( 1998 ) observation of mated female adélie penguins copulating with males other than their mate in exchange for rocks on which to lay their eggs . but in this case , the harlotry could conceive , so it isn ' t a clear example of non - reproductive sex .
alexander gm , wilcox t , farmer me . hormone - behavior associations in early infancy .
effects of discrete lesions of the sexually dimorphic nucleus of the preoptic area or other medial preoptic regions on the sexual behavior of male rats .
giffney , noreen , and myna hird . queering the non / human . aldershot , uk : ashgate , 2008 .
weatherhead pj , prosser mr , gibbs hl , brown gp ( 2002 ) male reproductive success and sexual selection in northern water snakes determined by microsatellite dna analysis . behavioral ecology 13 : 808–815 .
on the other hand there are many ways in which we cannot help behaving just as animals do — or mammals , anyway — and sex is one of the most obvious ones . we copulate , as they do . they have penises and vaginas , as we do , and the fact that the vagina of a calf can be sexually satisfying to a man shows how similar these organs are . the taboo on sex with animals may , as i have already suggested , have originated as part of a broader rejection of non - reproductive sex . but the vehemence with which this prohibition continues to be held , its persistence while other non - reproductive sexual acts have become acceptable , suggests that there is another powerful force at work : our desire to differentiate ourselves , erotically and in every other way , from animals .
jones ba , shimell jj , watson nv . pre - and postnatal bisphenol a treatment results in persistent deficits in the sexual behavior of male rats , but not female rats , in adulthood .
when non - reproductive sex is more accessible than reproductive sex , animals might pursue it for practice . li et al . ( 2007 ) noticed that during the mating season , some male macaques wouldn ' t tolerate other males copulating with females , particularly if the copulating male was adolescent or ranked below the other male . the lower stakes outside of the mating season would probably be a better time for males to practice sex .
the changing aspects of an individual ' s sexual attitudes , behaviors , feelings , and roles can be described by the term ? psychophysiological development . sexual life cycle . psychosexual development . sexual maturation .
] . sexual orientation also has been reported for two male infants who were reassigned as girls because of severe penile damage in infancy . one of these individuals had primary sexual interest in women in adulthood , whereas the other had sexual interest in both women and men [
“a brilliant and important exercise in exposing the limitations of received opinion . . . an exhaustively argued case that animals have multiple shades of sexual orientation . ” ― publishers weekly
a brilliant and important exercise in exposing the limitations of received opinion . . . an exhaustively argued case that animals have multiple shades of sexual orientation .
publishers weekly
the dsm - 5 identifies sexual dysfunction as a . a diminution of sexual functioning in one of the four phases of sexual response . b . a pathological inability to regulate arousal states , to delay or achieve ejaculation , and / or to control orgasms . c . a disturbance in sexual desire and in the psychophysiological changes characterizing the sexual response cycle that causes marked distress and interpersonal difficulty . d . psychological or physical impairments to achieving sexual fulfillment .
in order to understand queer animals , alaimo employs haraway’s “naturecultures” as the environment within which fluidity and plurality of sexuality can be achieved . she shows how non - human animals are cultural beings entwined in social interactions . alaimo adopts a perspective similar to bagemihl’s , as she longs for a reconfiguration of the distinctions between nature and culture :
# savebenjy , as the campaign was called , captures a marked shift in cultural attitudes towards homosexuality in ireland . this essay considers the discourse of sexuality , both in the historical and irish cultural context . foucault’s the history of sexuality vol . 1 ( 1976 ) identified how sex was brought into biological discourses , where it could be studied and explained and , by the nineteenth century , how heterosexual reproductive sex was promoted as the norm . same - sex non - reproductive behavior was made “deviant” with strict laws and prohibitions . in ireland , the doctrine of the catholic church emphasized chastity and restraint , and sex was confined to the married heterosexual couple , while same - sex non - reproductive activity was a criminal offence .
lockhart ab , thrall ph , antonovics j . sexually transmitted diseases in animals : ecological and evolutionary implications .
nadler rd . homosexual behavior in nonhuman primates in : mcwhirter dp , sanders sa , reinisch jm , editors .
sexual differentiation of aromatase activity in the rat brain : effects of perinatal steroid exposure .
female sexual initiation in early and late adolescence in three females who first ovuluted during early adolescence , illustrating that the frequency of sexual initiation increased from early to late adolescence .
homosexuality is a social phenomenon and is most widespread among animals with a complex herd life .
animals are expected to defend feeding territories when food is widely distributed . true or false .
manson , j . h . , perry , s . , & parish , a . r . ( 1997 ) . nonconceptive sexual behavior in bonobos and capuchins .
a brilliant and important exercise in exposing the limitations of received opinion . . . an exhaustively argued case that animals have multiple shades of sexual orientation .
- - publishers weekly
takahata y ( 1980 ) the reproductive biology of a free - ranging troop of japanese monkeys . primates 21 : 303–329
a . focused on biological function , behavior , body awareness , and acceptance .
further research on species in which sexual dimorphism is prominent but sexual segregation is absent ( watts 2005 ) or on species in which sexual segregation occurs in the absence of a sexual dimorphism in size ( such as in bats ) ( altringham and senior 2005 ; senior et al . 2005 ) would be extremely important for understanding the underlying causes and mechanisms of sexual segregation , not just in ungulates , but in all sexually segregating species . finally , the examples of sticklebacks and guppies show how powerful an experimental approach can be in elucidating proximate and ultimate causes of sexual segregation .
there are hundreds of examples of non - reproductive sex among animals , from albatrosses to koalas . but none of these examples can make people quite so uncomfortable as bonobos do . two bonobo females having sex looks very different than two female albatrosses sitting placidly on their nest . bonobo sex looks human . [ biologists : media sensationalizes animal sex ]
gavin l , mackay ap , brown k , et al . centers for disease control and prevention ( cdc ) sexual and reproductive health of persons aged 10–24 years – united states , 2002–2007 .
altered sexual partner preference in male ferrets given excitotoxic lesions of the preoptic area anterior hypothalamus .
shine r ( 1994 ) sexual size dimorphism in snakes revisited . copeia 1994 : 326–346 .
chadwick - jones jk . presenting and mounting in non - human primates : theoretical developments . j soc biol struct . 1989 ; 12 : 319–33 .
wallen k , winston la , gaventa s , davis - dasilva m , collins dc . periovulatory changes in female sexual behavior and pattern of ovarian steroid secretion in group - living rhesus monkeys .
. . . and animals don ' t live off 2000 year old books filled with bs .
your logic says that police dogs , service animals , and sporting animals are abused . some can be , but i believe a lot of them enjoy themselves . simple minds , simple lives .
bao am . , swaab df . sex differences in the brain , behavior , and neuropsychiatric disorders .
the development of brain circuitry controlling the sexual dimorphism in urination behavior is influenced by the levels of estrogen or testosterone that are circulating in the blood during the early postnatal period . estogren must prevent the development of the neuronal patterns of connectivity that are responsible for the male behavior .
) . thus , a female might have a stronger rank - related suppression of sexual behavior early in adolescence than late in adolescence . finally , the early adolescent females may be less sensitive to the effects of estradiol on sexual motivation than are late adolescent females . if this were true , follicular increases in estradiol , while sufficient to trigger ovulation , may be insufficient to increase sexual initiation . probably , age - related differences result from some combination of experiential differences , changes in social status , or sensitivity to hormones , with no single factor accounting for the differences . whatever the cause , this change in sexual behavior across development reinforces the notion that rhesus female sexual behavior is sensitive to both the hormonal and social environments .
a brilliant and important exercise in exposing the limitations of received opinion . . . an exhaustively argued case that animals have multiple shades of sexual orientation .
- -
publishers weekly
then in 1999 , bruce bagemihl published
biological exuberance : animal homosexuality and natural diversity
( st . martin ' s press ) , one of the first books of its kind to provide an overview of scholarly studies of same - sex behavior in animals . bagemihl said homosexual behavior had been documented in some 450 species .
it says sex between animals - as between humans - is often a matter of enjoyment , rather than procreation , and that this applies to animals of the same sex as well as opposite sexes .
discover new insights into neuroscience , human behavior and mental health with scientific american mind .
wallen , k . ( 1995 ) . the evolution of female sexual desire . in p . abramson and s . pinkerton ( eds . ) . sexual nature , sexual culture ( pp . 57–79 ) . chicago : university of chicago press .
this purification of sex manifested itself through catholic doctrine in ireland , and homosexual non - reproductive sexual behavior was now identified as deviant . queer theorist gayle rubin describes mistreatment of homosexuals in the us during the 1950s , from frequent police raids to queer bashing . the us gay rights movement in the 1970s led to a rethinking of what it meant to be gay or lesbian , and brought about a radical new era when sexual preferences could no longer be viewed as legitimate grounds for discrimination . ireland’s movement towards becoming a more tolerant country would take another 20 years .
vasey pl , sommer v . homosexual behaviour in animals : topics , hypotheses and research trajectories . in : sommer v , vasey pl , editors . homosexual behaviour in animals : an evolutionary perspective . cambridge : cambridge university press ; 2006 . p . 3–42 .
nottebohm f . , arnold ap . sexual dimorphism in vocal control areas of the songbird brain .
behavior . in j . e . reynolds iii & s . a . rommel ( eds . ) ,
other animals appear to go through a homosexual phase before they become fully mature . for instance , male dolphin calves often form temporary sexual partnerships , which scientists believe help to establish lifelong bonds . such sexual behavior has been documented only relatively recently . zoologists have been accused of skirting round the subject for fear of stepping into a political minefield .
see william simon and john h . gagnon , ‘sexual scripts : permanence and change’ , archives of sexual behavior , 15 / 2 ( 1986 ) , 97–120 ; william simon , postmodern sexualities ( london : routledge , 1999 ) , 40–58 .
demonstration of a sexual dimorphism in the distribution of serotonin - immunoreactive fibers in the medial preoptic nucleus of the rat .
clutton - brock th ( 1988 ) reproductive success : studies of individual variation in contrasting breeding systems . chicago , il : university of chicago press .
this is the first published article on the biology of c . vacariensis ; its main goal is to study the reproductive cycle and sexual dimorphism of the species . the following questions are addressed : ( 1 ) are the reproductive activity and cycles of stored fat seasonal or continuous ? ( 2 ) what is the reproductive cycle of males and females ? ( 3 ) at which snout - vent length ( svl ) do males and females reach sexual maturity ? ( 4 ) what is the effect of environmental factors ( temperature , photoperiod , precipitation ) on the reproductive activity and body fat cycles ? ( 5 ) what is the clutch size ? ( 6 ) does clutch size depend on female size ? ( 7 ) is there any sexual dimorphism in morphological characteristics and in the coloration pattern ?
human masturbation is typically coupled with imagined or observed sexual behavior ( e . g . pornography ) , while masturbation in other primates typically occurs in isolation or independent of the sexual behavior of others , and likely does not involve developed mental sexual imagery given the presumed human uniqueness of this capacity . human masturbation also seems to be more ubiquitous across individuals , and may display different patterns compared to other primates , though data on this subject is limited .
vasey pl , sommer v . homosexual behaviour in animals : topics , hypotheses and research trajectories in : sommer v , vasey pl , editors .
carothers , j . h . 1984 . sexual selection and sexual dimorphism in some herbivorous lizards . the american naturalist 124 ( 2 ) : 244 - 254 . [ links ]
female sexual initiation in high , middle , and low ranked females during late adolescence , illustrating that high ranked females had higher levels of sexual initiation and a less tight coupling of behavior with the periovulatory period of their ovarian cycles than did middle and low ranked females .
can refer either to a particular behavior when it occurs between two men or two women , or to an individual whose primary
identity
involves any or all of these activities . since the notion of identity is inappropriate to ascribe to animals , these terms will be reserved for the behaviors that animals engage in and , where relevant , to describe individuals whose primary
orientation
is toward animals of the same sex where courtship , sexual , and / or pair - bonding activities are concerned . in addition , because the terms
] , but this curvilinear relationship , as opposed to a linear relationship , had not been predicted . these studies were part of a larger project that also measured looking preferences for social / non - social stimuli , non - verbal communicative gestures , verbalizations , pretend play , and empathy [
altmann j ( 1974 ) observational study of behavior : sampling methods . behaviour 49 : 227–267
tutin ceg , mcgrew wc ( 1973 ) chimpanzee copulatory behavior . folia primatol 19 : 237–256
hormones , brain and behavior . vol 3 . san diego , ca : academic press .
jia zy , jiang zg , wang zw ( 2000 ) observation on the behaviors of masked palm civet in reproductive season . acta theriol 20 : 108–115 .
derickson , w . k . 1976b . ecological and physiological aspects of reproductive strategies in two lizards . ecology 57 : 445 - 458 . [ links ]
the relationship of male - male mounting to the sexual preferences of young rams .
bradbury jw ( 1977 ) lek mating behavior in the hammer - headed bat . z tierpsychol 45 : 225–255 .
one of the most important findings in kinsey ' s work was that a . children had sexual thoughts and experiences . b . few people understood or used contraceptive devices . c . there was extraordinary diversity in sexual behavior . d . a vast majority of women masturbated several times a day .
anate m . vaginal trauma at sexual intercourse in llorin , nigeria . an analysis of 36 cases .
by invoking examples of how we humans have decided that we do have an ethical obligation to the sentient animals in our care like neglect and abuse laws , i was using the above proposition to argue for the ethical treatment of animals .
homosexuality in its myriad forms has been scientifically documented in more than 450 species of mammals , birds , reptiles , insects , and other animals worldwide .
reeder dm ( 2003 ) the potential for cryptic female choice in primates : behavioral , anatomical , and physiological considerations . in : jones cb , editor . sexual selection and reproductive competition in primates : new perspectives and directions . norman : american society of primatologists . pp . 255–303 .
meyer - bahlburg hfl , dolezal c , baker sw , new mi . sexual orientation in women with classical or non - classical congenital adrenal hyperplasia as a function of degree of prenatal androgen excess . arch sex behav . 2008 ; 37 : 85–99 .
hines m , brook c , conway gs . androgen and psychosexual development : core gender identity , sexual orientation and recalled childhood gender role behavior in women and men with congenital adrenal hyperplasia ( cah )
mallard ducks are reported to both attempt to rape ducks of the same sex , as well as practice necrophilia . either of those should qualify on some level as non - reproductive sex , even if not consensual for the one in a pickle . this discovery earned kees moeliker the ig nobel prize in 2003 . the guardian reports :
in addition to physical injury and increased risk of disease , sexual intercourse and pregnancy increase opportunity for predation and use energy that could enhance survival . the occurrence of nocturnal mating , rapid sexual intercourse , and cryptic mating are all adaptations that counter this risky aspect of sexual intercourse . given the significant risks associated with sexual reproduction , why does it occur ?
reproductive cycle . the available data indicate that c . vacariensis has a seasonal and discontinuous reproductive cycle , as it has been found for other lizard species that inhabit regions with seasonal climatic factors ( precipitation and / or temperature ) ( e . g . magnusson , 1987 ) .
sex when the female is nonfertile would have little evolutionary consequence if sex also occurred during fertility . thus , the coupling of increased sexual motivation with peak fertility through changes in the same hormones increases reproductive success and still allows the occurrence of sexual behavior in nonreproductive contexts . a reliance upon sexual motivation as the mechanism coordinating fertility with sexual behavior produces a less tight coupling between hormonal and behavioral change in primates than that seen in nonprimate species ( wallen , 1990 ) . a loose coupling between hormonal changes and behavior would be at a selective disadvantage compared to a strict coupling if the loose coupling reduced the likelihood of mating when the female is fertile . however , if mating during peak fertility was the same , but additional mating occurred at nonfertile times , there would still be some selection against nonreproductive mating due to the risks posed by mating itself .
fleming a . s , vaccarino f , luebke c . amygdaloid inhibition of maternal behavior in the nulliparous female rat .
leckman j . f , et al . the role of central oxytocin in obsessive compulsive disorder and related normal behavior .
constantinescu m , hines m . relating prenatal testosterone exposure to postnatal behavior in typically developing children : methods and findings .
talmage - riggs g , anschel s . homosexual behavior and dominance hierarchy in a group of captive female squirrel monkeys (
yes , and nearly 100 % of animals with mate with their own offspring . many species eat their young .
curators say a norwegian exhibition on homosexuality among animals has been well received , despite initial indications of strong opposition .
pomerantz sm , goy rw . proceptive behavior of female rhesus monkeys during tests with tethered males .
sexual dimorphism in the preoptic / anterior hypothalamic area of ferrets : effects of adult exposure to sex steroids .
beach fa ( 1976 ) sexual attractivity , proceptivity and receptivity in female mammals . horm behav 7 : 105–138
) also showed a peak in female sexual initiation at midcycle , but showed much lower levels of sexual initiation than the higher ranked female . finally , the third female who ovulated ( ys5 ,
and those acts need to be discussed to have an accurate understanding of biology . the exhibit continuously states that non - reproductive sex acts form the foundation of many vertebrate social structures . without those social groups , the animals would perish . in that way , behavior that does not result in mating , and thus would otherwise be considered
evolutionarily useless
, proves its worth by increasing the survivability of the various members of the group by strengthening cohesion and diffusing tension . that argument about evolution underlies one of the two implicit messages of the exhibit .
norvell mk , benrubi gi , thompson rj . investigation of microtrauma after sexual intercourse .
andersson m ( 1994 ) sexual selection . princeton , nj : princeton university press .
d . sexual arousal by the real infliction of physical or psychological harm to another .
a . giving and receiving pleasure to each other without a sexual or coital goal .
palavras - chave : teiidae , cnemidophorus vacariensis , reprodução , dimorfismo sexual , conservação .
all the incidents recorded by harris and her coauthors took place in monterey bay . however , harris told discovery news ,
given that we documented interspecific sexual interactions involving at least three different male otters and that similar behavior has been described in many wildlife species , it is certainly possible that this behavior could be occurring elsewhere in the range .
yet scientists say we should be wary of referring to animals when considering what ' s acceptable in human society . for instance , infanticide , as practiced by lions and many other animals , isn ' t something people , gay or straight , generally approve of in humans .
) . these studies estimate from sequence disruptions that more than 30 % of olfactory receptor genes are non - functional pseudogenes in non - human primates , rising to more than 60 % in the human genome . coupled with these genetic changes , there has also been a dramatic reduction in the size of the olfactory cortex , from 65 % of total cortex in insectivorous mammals to less than 5 % in old world primates (
labad j , menchon j . m , alonso p , segalas c , jimenez s , vallejo j . female reproductive cycle and obsessive–compulsive disorder .
the counterexample would be that we ' re treating animals in all kinds of ways that are not in their interest or involve not
getting their consent
.
furuichi t , connor r , hashimoto c . non - conceptive sexual interactions in monkeys , apes , and dolphins . in : yamagiwa j , karczmarski l . , editors . primates and cetaceans : field research and conservation of complex mammalian societies . tokyo : springer . p . 385–408 .
anderson , r . a . & vitt , l . j . 1990 . sexual selection versus alternative causes of sexual dimorphism in teiid lizards . oecologia 84 : 145 - 157 . [ links ]
depicts the frequency of female sexual initiation in high , middle , and low ranked control females . the two high ranked females initiated sexual interactions with the highest frequency and for longer periods prior to ovulation . both middle and low ranked females had peaks in sexual initiation behavior at midcycle , but had lower levels than high ranked females during the follicular phase . thus , middle and low ranked late adolescent females demonstrated an adult - like pattern of a shorter period of follicular female initiation , lower levels of behavior , and a tighter coupling of behavior with the periovulatory period than that of high ranked late adolescent females .
bagemihl details how many ethologists and other researchers disregarded any same - sex behavior that is not overt sex , calling it imitation of heterosexuality ( pseudoheterosexuality ) , substitute activity in the absence of the opposite sex , a mistake , or a pathological condition , seeking to explain the behavior rather than understand it . bagemihl claims that the preconceived notions of heteronormative sexual activity in non - human animals are grounded in the traditional “noah’s ark view” of the animal kingdom , where “biology revolves around two sexes , male and female , with one of each to a pair” ( 36 ) . ecologist joan roughgarden equates the homophobia in science with a “cover up” ( 128 ) .
magnusson , w . e . 1987 . reproductive cycles of teiid lizards in amazonian savanna . journal of herpetology 21 ( 4 ) : 307 - 316 . [ links ]
several psychological adaptations crucial to sexual behavior parallel the physiological and behavioral adaptations controlled by gonadal hormones . successful reproduction requires intimate social contact , which provides the opportunity for the evolution of male selection based on physical and behavioral characteristics . it is beyond this review to cover this vast area . instead we focus on the psychological processes that regulate the occurrence of sexual behavior in females and coordinate mating with fertility .
nadler rd . homosexual behavior in nonhuman primates . in : mcwhirter dp , sanders sa , reinisch jm , editors . homosexuality / heterosexuality : consepts of sexual orientation . new york : oxford university press ; 1990 . p . 138–70 .
is it if you want to be dirty be dirty a freedom of practice ? there is a general opinion about animals ' behavior . they refer to a man who is dummy an ass , a coward a chicken , a dirty a pig or an ape . something is described as in human opposite savage . animals learning from humans in the circus have succeeded in teaching man how to behave like them .
barouki r , gluckman pd , grandjean p , hanson m , heindel jj . developmental origins of non - communicable disease : implications for research and public health .
unfortunately , the extant research doesn ' t clearly support any one explanation of all these behaviors across all these species . perhaps this shouldn ' t be a surprise . in this chapter , i enumerate some of the available explanations and the evidence for them . they aren ' t mutually exclusive , but nor are there any proposals of how to integrate them into a coherent theory of non - reproductive sexual behavior . therefore , the adaptive value of sexuality—the one domain of life that evolutionary psychology would presumably most easily explain—is in fact an open question .
wilson me , gordon tp , blank ms , collins dc . timing of sexual maturity in female rhesus monkeys (
could the indirect competition hypothesis explain inter - sexual site segregation in red deer ( cervus elaphus l . ) ?
altmann , j . , hausfater , g . , & altmann , s . a . ( 1998 ) . determinants of reproductive success in savannah baboons . papio cynocephalus in t . h . clutton - brock ( ed . ) . reproductive success : studies of individual variation in contrasting breeding systems ( pp . 403–418 ) . chicago : the university of chicago press .
janet mann , a professor of biology and psychology at georgetown university who has studied same - sex behavior in dolphin calves , says their homosexuality
is about bond formation , not about being sexual for life .
roy and silo are hardly unusual . indeed , scientists have found homosexual behavior throughout the animal world .
for intelligent species , the benefits are exactly the same as in intercourse with birth control - no offspring are produced , but people still seem to get something out of it . even for non - intelligent creatures , the usual non - procreative reasons still apply ( pleasure , dominance , social cohesion and conflict resolution , prostitution , etc . ) .
licht , p . & gorman , g . c . 1970 . reproductive and fat cycle in caribbean anolis lizards . university of california publications in zoology 95 : 1 - 52 . [ links ]
sexual health is a . focused on biological function , behavior , body awareness , and acceptance . b . focused on our mental health and our attitudes toward sexuality . c . primarily focused on our physical well - being . d . focused on sexual function and sexually transmitted diseases .
] . the effects of early androgen exposure on both the brain and behavior are often described as organizational , and early androgen exposure is thought to produce enduring changes in behavior by altering the development and organization of underlying brain circuits .
] . both outcomes are consistent with an influence of early androgen exposure on sexual orientation .
there were annual reproductive cycles in the study period ( fig . 1 ) . the peak of the reproductive cycle of males coincided with the peak of the female reproductive cycle . the testicular volume was highest in october / november ( = 72 . 2 ± 29 . 6 mm 3 ; n = 17 ) , and lowest in february ( = 8 . 9 ± 2 . 1 mm 3 ; n = 6 ) ; females were able to reproduce between october and december , and they were nonreproductive between january and september .
by the fall breeding season around 3 . 5 years of age , all adolescent females have ovulatory menstrual cycles , and most conceive ( wilson et al . , 1982 ; wilson et al . , 1983 ; zehr , 2002 ) . in general , late adolescent females engage in sexual behavior for longer periods than do adults , due to increased estradiol earlier in the follicular phase ( wilson et al . , 1982 ) . in adult females , social rank modulates the length of behavioral estrus , with high ranked females mating for longer periods of time prior to ovulation than lowed rank females ( wallen , 1990 ) . this section describes female sexual initiation in late adolescent females of high , medium , and low rank to determine if late adolescent females have rank - related modulation of female sexual behavior similar to that seen in adult females . in addition , this section explores age - related differences in female sexual initiation by comparing sexual behavior in early and late adolescence for those females who ovulated in early adolescence .
the existence of sexual contact between humans and animals , and the potency of the taboo against it , displays the ambivalence of our relationship with animals . on the one hand , especially in the judeo - christian tradition — less so in the east — we have always seen ourselves as distinct from animals , and imagined that a wide , unbridgeable gulf separates us from them . humans alone are made in the image of god . only human beings have an immortal soul . in genesis , god gives humans dominion over the animals . in the renaissance idea of the great chain of being , humans are halfway between the beasts and the angels . we are spiritual beings as well as physical beings . for kant , humans have an inherent dignity that makes them ends in themselves , whereas animals are mere means to our ends . today the language of human rights — rights that we attribute to all human beings but deny to all nonhuman animals — maintains this separation .
females begin to engage in sexual behavior during the breeding season around 2 . 5 years of age . however , since few females are likely to ovulate or conceive around 2 . 5 years of age ( wilson & gordon , 1989 ; wilson , gordon , blank , & collins , 1984 ; wilson et al . , 1986 ; wilson et al . , 1983 ) , studies of adolescent sexual behavior have primarily focused on females 3 . 5 years of age or older ( pope , gordon , & wilson , 1986 ; wilson & gordon , 1980 ; wilson , gordon , et al . , 1984 ; wilson , et al . , 1982 ) . this section describes sexual initiation behavior in both ovulating and nonovulating early adolescent females . if circulating hormones and sexual initiation are tightly coupled in early adolescence , all ovulating females would display sexual initiation behavior and only ovulating females would be sexually active . our data suggest comparable flexibility in the sexuality of adolescent females to that seen in adult females .
is the first comprehensive account of the subject , bringing together accurate , accessible , and nonsensationalized information . drawing upon a rich body of zoological research spanning more than two centuries , bruce bagemihl shows that animals engage in all types of nonreproductive sexual behavior . sexual and gender expression in the animal world displays exuberant variety , including same - sex courtship , pair - bonding , sex , and co - parentingeven instances of lifelong homosexual bonding in species that do not have lifelong heterosexual bonding .