mesocyon is an extinct genus of terrestrial carnivore within the family canidae , subfamily hesperocyoninae , which inhabited north america from the early oligocene to early miocene 38.9 — 20.6 ma , existing for approximately 18 million years .

though a carnivore , dentition suggests this animal was a hypercarnivore or mesocarnivore .

mesocyon

place mesocyon coryphaeus has been collected from central oregon in the john day formation , and in california .
mesocyon coryphaeus ; ypm vp 012701 ; north america ; usa ; oregon ; leander s . davis , sam h . snook ; 1874
mesocyon coryphaeus ? ; ypm vp 043966 ; north america ; usa ; oregon ; sam h . snook , leander s . davis ; 1874
mesocyon coryphaeus det . by : xiaoming wang 1994 ; see : wang , xiaoming . 1994 . phylogenetic systematics of the hesperocyoninae ( carnivora : canidae ) . bulletin of the american museum of natural history . 221 : 207pp . mesocyon coryphaeus det . by : malcolm r . thorpe
above : 30 million year old dog skeleton , mesocyon coryphaeus ( joda 3366 ) , included in the new study . below : mural from john day fossil beds nm depicting several early dogs ( mesocyon ) chasing a 3 - toed horse ( miohippus ) through an ancient forest .
cynodesmus thooides has a brain that is of similar size and external anatomy to that of mesocyon . the cerebral cortex of cynodesmus seems somewhat less expanded than in mesocyon . it has two main sulci , the coronolateral and suprasylvian , but lacks the ectolateral sulcus , while the ectosylvian sulcus is represented by a series of variable depressions ( fig . 13 ) . an advance over mesocyon is the presence of a small presylvian sulcus .
mesocyon coryphaeus ; ypm vp 012723 ; north america ; usa ; oregon ; wheeler county ; leander s . davis ; 1874 - 07 - 06
mesocyon coryphaeus ; ypm vp 012701 . a ; north america ; usa ; oregon ; leander s . davis , sam h . snook ; 1874
mesocyon coryphaeus ; ypm vp 012710 ; north america ; usa ; oregon ; wheeler county ; sam h . snook ; 1874 - 07 - 06
mesocyon coryphaeus ; ypm vp 012709 ; north america ; usa ; oregon ; wheeler county ; leander s . davis ; 1874 - 03 - 11
phylogenetic position ― this is the most diverse lineage of hespero - cyonines , beginning with mesocyon , and leading to enhydrocyon through the transitional forms cynodesmus , sunkahetanka and philotrox . the lineage is characterized by an increased trend towards hypercarnivory . endocranial material is known from three genera : mesocyon , cynodesmus and enhydrocyon .
mesocyon coryphaeus ; ypm vp 012723 . b ; north america ; usa ; oregon ; wheeler county ; leander s . davis ; 1874 - 07 - 06
a mural from john day fossil beds national monument depicts several early dogs ( mesocyon ) chasing a 3 - toed horse ( miohippus ) through an ancient forest in oregon .
mesocyon coryphaeus det . by : xiaoming wang 1994 ; see : wang , xiaoming . 1994 . phylogenetic systematics of the hesperocyoninae ( carnivora : canidae ) . bulletin of the american museum of natural history . 221 : 207pp . mesocyon brachyops det . by : malcolm r . thorpe ; see : thorpe , malcolm r . 1922 . oregon tertiary canidae , with descriptions of new forms . american journal of science . ( 5 ) iii : 162 - 176 .
the brains of the derived oligocene hesperocyonines , mesocyon , cynodesmus and enhydrocyon , have a more expanded cerebral cortex . the brain of mesocyon is slightly more advanced than that of cynodesmus . in mesocyon there is an ectolateral and an ectosylvian sulcus , while in cynodesmus there is no ectolateral sulcus and only a series of variable depressions in the place of the ectosylvian sulcus . however , cynodesmus does have a presylvian sulcus . the brain of enhydrocyon has four neocortical sulci ( coronolateral , suprasylvian , ectosylvian and presylvian ) . the most important difference between enhydrocyon and its ancestor ( cynodesmus ) is that its brain has very high frontal lobes , a feature that is related to its cranial morphology ( short rostrum ) .
description mesocyon was a short - faced canid , about the size of a coyote . like all true dogs , it had legs adapted for running , had large earbones that were adapted for better hearing , and a dentition that functioned both in shearing flesh and in crushing bones .
the brain of mesocyon is almost twice as large as that of hesperocyon . the general appearance of the brains of the two genera is similar . the frontal and temporal lobes are small , the rhinal sulcus of mesocyon is somewhat lower than that of hesperocyon , the overlap of the cerebellum is small and the posterior cerebellar vermis is straight . an advance in mesocyon over hesperocyon is the appearance of two more sulci ; in addition to the coronolateral and suprasylvian sulci , there are also an ectolateral and an ectosylvian sulci . the ectolateral sulcus is short , but well defined . the ectosylvian sulcus is well defined on one side , and shallower and broken in two parts on the other ( fig . 12 ) , a condition that is seen in both specimens . in amnh 6946 , the coronolateral sulci diverge posterolaterally significantly more than in amnh 6920 .
the extinct omnivorous boraphagine canid , phlaocyon , extant bush dog , bonecrushing hesperocyon canid , paraenhydrocyon , and hesperocyon canids mesocyon coryphaeus and hesperocyon gregarius had most impressive scores for canids . additionally , the dhole scored much more impressively than other social canids like wolf , dire wolf , and awd .
material ― mesocyon coryphaeus amnh 6920 - oligocene of camp creek , john day basin , oregon , u . s . a . partial skull and a plaster copy of its nearly complete endocranial cast ; the skull roof is restored and , therefore , the original endocast is presently unavailable . the olfactory bulbs and part of the cerebrum are hidden within the cast of the nasal cavities ( fig . 12e - g ) . the specimen was used by radinsky ( 1973 ) , together with amnh 6946 and f : am 63373 ( a cynodesmus , see below ) for a composite description of the mesocyon brain .
mesocyon had what scientists call digitigrade feet , which means that it was able to stand or walk on its toes , an adaptation that increased stride length and thus speed . when paleontologists examine these fossils , they see that the long bones of the toes are packed very close together , unlike what we see in plantigrade animals , or those that walk flat - footed .
description and comparisons ― scott ( 1895 ) described the brain of cynodesmus ypm - pu 10412 , and radinsky ( 1973 ) gave more extensive composite descriptions of mesocyon and cynodesmus brains based on ypm - pu 10412 , amnh 6946 , f : am 63373 and f : am 61300 . however , after the extensive work on canid phylogeny of recent years , many specimens have been taxonomically re - assigned . as a consequence , f : am 63373 is no longer considered mesocyon , but cynodesmus ( according to wang , 1994 ) . on the other hand , f : am 61300 is not cynodesmus , and certainly not “ cynodesmus petersoni , ” which is a nomen nudum ( wang , 1994 ) , but the borophagine desmocyon matthewi ( wang et al . , 1999 ) . as a result , it has become evident that several anatomical features were attributed by radinsky ( 1973 , p . 174 ) either to the wrong taxon or were characterised as “differences [ of ] evolutionary significance or [ reflecting ] individual variation . ” therefore , in order to avoid confusion , the brains of mesocyon and cynodesmus are redescribed herein .
specimen count 1 record last modified 5 jul 2018 skeletal morphology skull . mandible , teeth ; updated geological age cenozoic - neogene - miocene - arikareean upper stratigraphy john day fm nmnh - paleobiology dept . taxonomy animalia chordata mammalia carnivora canidae see more items in paleogeneral mammals terrestrial - neogene mammalia miocene arikareean john day paleobiology place oregon , united states collection date 14 jul 1882 usnm number v23112 published name mesocyon sp
mesocyon sp . amnh 6946 - early arikareean ( late oligocene ) , turtle cove of john day formation , oregon ( no locality data ) , u . s . a . a complete and excellently preserved natural endocast ( fig . 12a - d ) . it was figured by edinger ( 1956 ) under the name daphoenus , and described and figured by radinsky ( 1969 , 1973 , 1978a ) .
description and comparisons ― the brain of osbornodon fricki is twice the size of that of mesocyon and six times the size of that of hesperocyon . its overall morphology has neither the rectangular outline of enhydrocyon nor the tapering brains of the other eocene - oligocene hesperocyonines . its frontal lobes are more developed that those of hesperocyon and mesocyon , the overlap of the cerebellum is larger , the olfactory bulbs are rostrally expanded and the cerebellar vermis is slightly twisted . the most important features of the o . fricki cerebral cortex were described by radinsky ( 1973 ) , who noted , in addition to the sulci seen on cynodesmus , a large orbital gyrus , a small sylvian sulcus , a complete ectosylvian sulcus and large cruciate depression . this depression is at the centre of the anterior part of the two coronolateral sulci , which come closer to the dorsal midline at the level of the frontoparietal suture and then bow out laterally . this was considered by radinsky ( 1973 , p . 178 ) as “the first appearance of a distinct sigmoid gyrus . ” this tendency also can be seen in mesocyon and cynodesmus , and even in a couple of hesperocyon specimens . however , it is in osbornodon fricki that it becomes evident .
record last modified 5 jul 2018 skeletal morphology skull . unspecified skull element ; updated geological age cenozoic - neogene - miocene - arikareean upper stratigraphy john day fm nmnh - paleobiology dept . taxonomy animalia chordata mammalia carnivora canidae collector william day see more items in paleogeneral mammals terrestrial - neogene mammalia miocene arikareean john day paleobiology place crook county , oregon , united states collection date jun 1883 usnm number v7744 published name mesocyon coryphaeus ( cope )
a , dinocrocuta gigantea ; b , crocuta crocuta ; c , parahyaena brunnea ; d , ikelohyaena abronia ; e , chasmaporthetes lunensis ; f , ictitherium sp . ; g , proteles cristata ; h , epicyon haydeni ; i , borophagus secundus ; j , microtomarctus conferta ; k , canis lupus ; l , lycaon pictus ; m , mesocyon coryphaeus . phylogenetic relationships for hyaenids ( a–g ) based on werdelin and solounias ( 1991 ) , and for canids ( h–m ) based on wang ( 1994 ) , wang et al . ( 1999 ) , and tedford et al . ( 2009 ) .
the cerebral cortex of the early miocene hesperocyonine , osbornodon fricki , is far more advanced than that of its oligocene relatives . in addition to the sulci seen in cynodesmus , it has a large orbital gyrus , a small sylvian sulcus , a complete ectosylvian sulcus and a large cruciate depression . the rostral parts of the coronolateral sulci bow out laterally , indicating a separation between the coronal and lateral parts , and the first appearance of the sigmoid gyri . although such a cortical pattern appears for the first time in osbornodon fricki , early signs of such an arrangement can be seen also in mesocyon and cynodesmus , and even in a couple of hesperocyon specimens .
( a ) contour plot depicted from the functions obtained in cva performed from the elbow shape of living predators and the predatory grouping . ( b ) elbow shape variation accounted for by the first canonical function . ( c ) elbow shape variation accounted for by the second canonical function . black arrows denote shape changes . ( d ) contour plot depicted from the functions obtained in cva performed from the elbow shape of living predators and the predatory grouping , but now including fossil forms . number indicates species : 1 , hesperocyon gregarius ; 2 , osbornodon fricki ; 3 , mesocyon temnodon ; 4 , enhydrocyon crassidens ; 5 , mesocyon coryphaeus ; 6 , archeocyon leptodus ; 7 , archeocyon falkenbachi ; 8 , phlaocyon leucososteus ; 9 , cormocyon haydeni ; 10 , desmocyon thomsoni ; 11 , cynarctus crucidens ; 12 , psalidocyon marianae ; 13 , epicyon saevus ; 14 , epicyon haydeni ; 15 , borophagus pugantor ; 16 , borophagus parvus ; 17 , borophagus secundus ; 18 , carpocyon webbi ; 19 , aelurodon asthenostylus ; 20 , aelurodon mcgrewi ; 21 , aelurodon taxoides ; 22 , aelurodon ferox ; 23 , leptocyon vulpinus ; 24 , leptocyon vafer ; 25 , leptocyon matthewi ; 26 , vulpes stenognathus ; 27 , urocyon minicephalus ; 28 , eucyon davisi ; 29 , canis thooides ; 30 , canis armbrusteri ; 31 , canis dirus ; 32 , canis lupus .
the brain of enhydrocyon stenocephalus is characterised by high and wide frontal lobes , resulting in a rectangular outline in dorsal view in contrast to the more tapering brains of all the other canids of the late eocene - early miocene . its brain has been described by radinsky ( 1973 , p . 176 ) , who noted about its sulcal . . . pattern that there is “a well defined ectolateral sulcus and an incomplete ectosylvian sulcus the left suprasylvian sulcus is broken with the two pieces slightly overlapped . a short presylvian sulcus delimits a narrow orbital gyrus . ” further , the rhinal sulcus is as high as in mesocyon and the overlap of the cerebellum , which has a straight cerebellar vermis , is small .
a . distribution of theoretical models overlaid with values from fe models of actual species , all scaled by total surface area . b , distribution of theoretical and actual models , the latter scaled by condylobasal length of the skull . red triangles indicate the theoretical pathway traveled by actual species on the functional landscape . the positions of hyaenid ( darker shade ) and canid ( lighter shade ) groupings are shown as ovals in ( b ) . species abbreviations ( hyaenids ) : ccr , crocuta crocuta ; hlu , chasmaporthetes lunensis ; iab , ikelohyaena abronia ; ict , ictitherium sp . ; pbr , parahyaena brunnea ; pcr , proteles cristata . canids : bor , borophagus secundus ; can , canis lupus ; epi , epicyon haydeni ; lpi , lycaon pictus ; mes , mesocyon coryphaeus ; mic , microtomarctus conferta . percrocutid : dgi , dinocrocuta gigantea .
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the ancestry of dog - like carnivores , as well as cat - like carnivores , goes back to the miacids , a group of carnivorans from some 45 mya , which shared certain features , miacids , such as tapocyon , had retractable claws like a cat , but had broad back molar teeth like a dog . these two groups diverged about 40 mya , with the ancestors of dogs , bears , weasels , raccoons , and seals going off in one evolutionary direction , while the ancestors of cats , hyenas , and civets diverged in another direction .
in our region these fossils were found at east lake and otay ranch , in chula vista , california .
ecology canids are genetically quite distinct from other groups . displaying great diversity , they are the most ancient of all the carnivorans . over a period of approximately 37 million years , at least 140 species of dogs evolved and became extinct in north america .
the trend toward greatly reduced forest lands and more open grasslands which occurred during the oligocene may have promoted the evolution of dog - like animals . we can hypothesize that dogs evolved and learned to run down their prey in environments where open grasslands became more common than thickly forested landscapes .
dogs exploited long - distance pursuit as a strategy for capturing prey in increasingly open habitats . cats do not do as well in open habitats as they generally stalk their prey , and need cover to hide behind .
as we observe in our own domestic dogs , fossil canids probably had an excellent sense of smell , a wide range of hearing , and good vision . they also had the advantage of being able to live on a variety of foods , and could be considered omnivores .
wild relatives living today include three families—wolves , foxes , and coyotes . they inhabit every continent except antarctica , so it is clear that they are adaptable to extremely variable habitats , from deserts to rain forests .
further investigation although scientists disagree as to how long ago dogs became domesticated , we do know that the human - canine connection goes way back , possibly as long as 15 , 000 years .
but how did dogs become domesticated ? many hypotheses exist , one being that dogs may have hung around places of early human occupation , scavenging scraps and benefiting from human hunting . perhaps they were used as a food source themselves . eventually their presence either became beneficial to humans in terms of their superior hearing and sense of smell , or some other factor came into play .
where did the first domesticated dogs occur ? some biologists have suggested that the dingoes of australian aborigines may have been the first domesticated dogs on earth , although other scientists hypothesize that domestication originated in asia .
genetic evidence indicates that domestic dogs came to the new world along with humans , migrating over the bering strait some 12 , 000 years ago . we still have much to learn about the process of the domestication of dogs .
suggested reading wayne , robert k . 1993 . phylogenetic relationships of canids to other carnivores . in miller ' s anatomy of the dog . philadelphia : w . b . saunders .
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det . by : xiaoming wang , 1994 ; see : wang , xiaoming . 1994 . phylogenetic systematics of the hesperocyoninae ( carnivora : canidae ) . bulletin of the american museum of natural history . 221 : 207pp .
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citation : tseng zj ( 2013 ) testing adaptive hypotheses of convergence with functional landscapes : a case study of bone - cracking hypercarnivores . plos one 8 ( 5 ) : e65305 . urltoken
editor : andrew a . farke , raymond m . alf museum of paleontology , united states of america
copyright : © 2013 zhijie jack tseng . this is an open - access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are credited .
funding : this research was supported by a national science foundation graduate research fellowship and a doctoral dissertation improvement grant ( deb - 0909807 ) , american society of mammalogists grant in aid of research , united states fulbright program , and a university of southern california zumberge grant . the funders had no role in study design , data collection and analysis , decision to publish , or preparation of the manuscript .
convergent evolution is a prominent feature of mammalian evolution in the cenozoic , so much so that many cases ( e . g . convergently fossorial , arboreal , herbivorous , or carnivorous forms ) have become textbook examples for the concept in evolutionary biology [ 1 ] . morphological convergence is often interpreted as being adaptive for the very reason that they appeared in unrelated clades of species . this study addresses two questions about macroevolutionary morphological convergence in mammalian skull morphology : ( 1 ) are morphologically convergent species actually convergent in functional capability ? ( 2 ) if so , do those morphologies occupy local optimal peaks in a “functional” landscape ? these questions are explored with theoretical morphology and finite element modeling in a case study of bone - cracking carnivorous mammals .
adaptation , like convergent evolution , is a central concept in evolutionary biology . studies of patterns and processes of adaptation on the macroevolutionary scale often rely on morphological characters , essentially those that are preserved in the fossil record . the concept of the fitness ( or adaptive ) landscape , as originally proposed to visualize possible evolutionary pathways of genetic interactions , has been adopted as a framework to examine morphology in evolutionary and ecological contexts [ 2 ] – [ 5 ] . in a demonstration of the concept at its extremes , kauffman [ 6 ] used simulations of hypothetical genetic interactions to create two fitness landscapes , one ( “fujiyama” landscape ) with a single adaptive peak , and the other with a random distribution of equally adaptive peaks . adaptive evolution is thought to proceed on intermediate landscapes between those extremes , with differentially elevated adaptive peaks , some of which act as “topological attractors” where examples of convergence can be sought [ 7 ] , [ 8 ] .
fea was originally an engineering technique , used in the design process to conduct mechanical testing on simplified , discrete representations of real - world objects . the term was coined by clough [ 23 ] for applications in the civil engineering field . in the past two decades , the application of fea to studies of vertebrate functional morphology has seen a notable increase , particularly in the study of the craniodental system [ 22 ] , [ 24 ] – [ 26 ] . application to mammalian craniodental biomechanics has been tested in a diverse range of research questions , from convergent evolution [ 27 ] , ecological niche [ 28 ] , conservation biology [ 29 ] , bite force [ 30 ] , to bone strain and model validation [ 31 ] , among others .
the initial input to fea is the morphology of interest , either derived from computer - generated models , photos of specimens , or more commonly , computed tomography ( ct ) images [ 21 ] . the representations of the morphology in question are modified and converted into element meshes , which are mathematical , geometric constructs of the original morphology . material properties and boundary conditions are assigned to the mesh model with values derived from experiments , or in the case of extinct organisms , experimental values taken from closely related living taxa [ 21 ] . fe analysis software programs can then perform simulations of forces on the fe model , returning results in the form of stresses , strains , and bite force [ 32 ] . the process of improving models of actual species , usually by digitally repairing incomplete areas of the structure of interest , is amenable to manipulation and creation of non - existing , theoretical shapes that can then be tested in the same way as a model of an actual species .
data for borophagine canids ( a–b ) and hyaenids ( c–d ) from two - dimensional geometric morphometric analyses in [ 10 ] . a , c , dorsal views ; b , d , lateral views . illustrations of skull show the measurements of width to length ( w∶l ) and depth to length ( d∶l ) taken from theoretical and actual skull shapes .
taking the evolutionary patterns observed previously for borophagine canids , hyaenids , and percrocutids , i test the hypothesis that bone - cracking ecomorphologies were specialized forms that converged on identical or equivalent functional peaks on a simplified form - function landscape . form and function are closely linked , so the functional pathways shared by bone - cracking ecomorphologies should reflect their parallel evolution in skull shape changes . secondly , the convergently evolved specialist species in both lineages occupy optimal peaks in the theoretical morphospace containing a wide range of possible morphologies . a novel “functional” landscape built using principles of functional morphology and theoretical morphology is presented as a framework to test these hypotheses . the general utility of such approach is then demonstrated by tracking evolution of craniodental function , as inferred from fea simulations , of actual fossil and extant species in the three carnivoran lineages discussed above .
the two main axes of cranial shape change formulated were used to form a two - dimensional morphospace analogous to raup ' s [ 17 ] classic “cube” of geometric parameters of shell coiling ( fig . 2 ) . the cranial parameters used here , however , do not constitute theoretical morphospace in the strict sense ; the direction of change along each morphological axis were chosen for analysis based on previous work using empirical morphospace [ 10 ] . this type of morphospace might also be referred to as a “combined” morphospace utilizing elements of both theoretical and empirical morphospaces [ 19 ] .
the hybrid morphospace occupied by the 36 models spanned d∶l ratios from 0 . 33 to 0 . 73 and w∶l ratios from 0 . 42 to 1 . 11 . theoretical skull shapes are shown in rostral - lateral view .
conventional adaptive landscapes rely conceptually on direct measures of survival and reproduction ; such measures are dependent on environmental and ecological conditions at the specific temporal and spatial scale being examined [ 5 ] , [ 16 ] . the creation of a functional landscape , as defined here , aimed to measure more universal features of craniodental systems based on biomechanics . bite force , regardless of the means for its estimation in living and extinct organisms , is one parameter that is crucial for vertebrates in both prey apprehension and mastication [ 60 ] , [ 61 ] . it is particularly important for bone - cracking ecomorphologies , as bite force is one direct determinant of the size of prey bone that can be consumed [ 39 ] , [ 62 ] . thus , the bite force performance of fossil and living carnivorans is expected to be of major importance .
similarly , it has been argued that skull strain energy , a measure of the work done in deformation of an object in fea simulations , is a suitable measure of functional efficiency [ 32 ] . this argument is based on the logic that biological objects ( e . g . skulls ) with maximum stiffness for a given volume of material ( i . e . low strain energy during deformation ) should be favored by selective processes that maximize functionality [ 32 ] . skull strain energy is used as a second axis of function in this study . the skulls of species in bone - cracking lineages are expected to be selected for increased stiffness per amount of skull bone , in order to perform the intensive bone - cracking behavior which places large amounts of stress and strain on the skull .
analogous to an adaptive landscape , where the third - dimension is a fitness axis used to document adaptive peaks and valleys over a bivariate plot of morphological parameters [ 8 ] , a functional landscape charts functional properties measured by a biomechanical axis over the bivariate plot of morphological parameters . the functional properties of bite force and skull strain energy are distinguished from measures of fitness because the former measure relatively narrow aspects of mastication , and not the overall organismal fitness or performance . nevertheless , for lineages such as hyaenids and borophagine canids that experienced directional evolution towards bone - cracking ecomorphologies , the two functional properties analyzed were probably important for bone - cracking performance .
the incremental changes in morphological parameters create hypothetical morphotypes that show variation along the same directions as observed empirically in hyaenids and canids ( fig . 2 ) . the association between parameters of skull shape and the ecological habits of extant carnivorans has been demonstrated in empirical morphospaces created by geometric morphometrics analyses [ 63 ] , [ 64 ] . conceptually , the morphological parameters used can be supplemented with other functionally relevant parameters that are particular to the research question being addressed . similarly , there may be other functional properties in addition to bite force and skull strain energy that are relevant to the specific type of functional morphology being examined . in its basic concept , the functional landscape is a functional manifestation of an adaptive landscape , its fitness axis ( commonly the z - axis ) having been modified to measure aspects of biomechanical function , which underlies organismal performance in relevant tasks .
theoretical morphotypes representing incremental deviation of the two morphological parameters were generated by modification of an ictitherium digital skull model . a complete and intact skull of the late miocene hyaenid ictitherium sp . ( hmv 0163 , hezheng paleozoology museum , gansu province , china ) was scanned using computed tomography ( ct ) at lanzhou university hospital no . 1 ( gansu province , china ) with a siemens somatom sensation 64 scanner ( 120 kv , 304 . 00 mas ) ; images had a pixel size of 0 . 2578 mm , resolution of 512×512 pixels , and 0 . 36 mm interslice distance . data were exported in the dicom ( digital imaging and communications in medicine ) format . the cranium and mandible of the specimen were separated and digitized using the software program mimics 13 ( materialise nv ) . digital reconstructions , including internal morphology , were exported in the stereolithography format ( * . stl ) . the files were then imported into geomagic studio 10 ( geomagic , inc . ) where generation of theoretical morphotypes took place .
skull depth and width in theoretical morphotypes were changed by scaling the original digital model of ictitherium in the respective axes by a set percentage ( 75 % –200 % of original ) . the axes of change were aligned so that depth increased along the line connecting the carnassial tooth and the top of the frontal dome ( figs . 1 – 2 ) ; width increased along the axis perpendicular to the long axis of the skull . the modified theoretical morphotypes were then exported into strand7 2 . 3 . 7 finite element analysis software program ( g + d computer pty ltd ) , where finite element meshes were generated .
three nodal constraints were placed on the cranium models : the left and right temporomandibular joints ( tmj ) , and the unilateral bite point . the bite point was modeled as a nodal constraint fixed from all translational and rotational movements . the tmj was modeled as a single nodal constraint in the middle of each glenoid fossa , fixed from all but rotational movement in the sagittal plane . all models were given a single set of material properties , representing typical values for mammalian cortical bone . all analyses were linear and static , therefore only two material parameters were required : young ' s ( elastic ) modulus = 20 gpa , and poisson ' s ratio = 0 . 3 . heterogeneous models that contain multiple material properties have been shown to have higher stresses and bite forces compared to identical models made with a single set of material properties ; such differences in results are acknowledged , but they are assumed to have no great effect on the comparative context being pursued in this study [ 25 ] , [ 52 ] , [ 55 ] .
bite force output is graphed as mechanical advantage ( ma ) and skull strain energy ( se ) values recorded in joules . both were plotted against bivariate plots of the two morphological parameters ( d∶l and w∶l ratios ) as wireframe plots , upon which simulation results from models of actual hyaenid and borophagine species were plotted ( fig . 3 ) .
w∶l and d∶l are plotted on the x - and y - axes , respectively . the functional properties mechanical advantage ( ma ) and skull strain energy ( se , in joules ) are plotted on the z - axis . a , d , three - dimensional plots of the data points from analysis of theoretical models ; b , e , the wire frame mesh overlaid and interpolated using the theoretical models ; c , f , the theoretical models removed , leaving the mesh representing the functional landscapes for ma and se , respectively . for data values see table s5 .
to use the functional landscape in predictions of functional evolution in actual lineages , the w∶l and d∶l ratios of actual hyaenids and canid species were measured from specimen photos . the dataset of fossil and extant hyaenids and canids from tseng and wang [ 10 ] was used . nine hyaenid species and 15 canid species were complete enough to be measured . means were used where sample size > 1 , and specimens that were used in fea ( see below ) were plotted individually ( table 1 , s1 , s2 ) .
list of actual models and species measurements of hyaenids and canids used in the study .
in addition to ma and se values , the stress distributions on the skulls of actual species were also visualized . values of von mises stress , which approximate materials that fail under a ductile mode of fracture , were used [ 26 ] , [ 73 ] . as fea conducted on models of actual species were scaled in a similar manner to the theoretical models , the distribution of von mises stress on the skull represents relative levels of stress that can be directly compared across species . high levels of stress under such comparisons can therefore be interpreted as likely areas of material failure .
the hybrid morphospace comprised 36 theoretical models , onto which a wire mesh was interpolated to create the functional landscapes ( figs . 2 – 3 ) . two separate landscapes were created , one for mechanical advantage ( ma ; fig . 3a–c ) and the other for skull strain energy ( se ; fig . 3d–f ) . the landscapes showed predictable trends of variation . increasing skull depth , regardless of the starting skull width , translated into higher ma and higher se ( fig . 3 ) . increasing skull width generated progressively lower ma and se at shallower skull depths , but the patterns became more complex at higher skull depths ( fig . 3 ) . peaks in ma are found at skull depth - to - length ( d∶l ) ratio of > 0 . 7 and width - to - length ( w∶l ) ratios of 0 . 4–0 . 7 ( fig . 3a–c ) . lowest ma values are found at d∶l < 0 . 4 and w∶l > 0 . 7 ( fig . 3a–c ) .
d∶l and w∶l ratios of actual hyaenid and borophagine canid species overlapped extensively in their distribution on the functional landscape ( fig . 4 ) . furthermore , the species followed an evolutionary pathway from d∶l 0 . 3–0 . 4 and w∶l 0 . 5–0 . 6 to d∶l ∼0 . 5 and w∶l ∼0 . 7 ( fig . 4a , d ) . this pathway showed a continuous climb towards higher elevation on the ma landscape ( fig . 4b ) , and a path into an adaptive valley on the se landscape ( figs . 4e ) . the pathways occupied by actual hyaenids and canids traversed a region of increasing ma and moderately low se , which is bordered at the bottom right with a large region of low ma and low se theoretical shapes ( fig . 5 ) . in the upper regions are high ma and high se shapes ; both of these regions represent suboptimal areas ( fig . 5 ) .
a , d , distribution of hyaenids ( dark circles ) and fossil canids ( light circles ) on two - dimensional contour plots of ma and se , respectively . lines are isoclines . b , e , distribution of hyaenid and canid species on the three - dimensional functional landscapes for ma and se , respectively . c , f , the pathways occupied by the hyaenid ( shaded ) and canid ( outlined ) lineages on the ma and se landscapes , respectively . sequential arrows indicate directions of change from less derived , earlier species to more derived , younger species . note continuous climb on the ma landscape and shifting towards shallower slopes on the se landscape . for data values of species models see table s6 .
small shaded squares represent theoretical models matched by existing hyaenid and canid species ( small unshaded square shows position of insectivorous proteles cristata ) . suboptimal regions are shown in larger squares . regions marked by parenthesized labels represent optimal areas not occupied by actual species .
the regions of the ma vs . se plot occupied by actual species represent a pathway from low ma ( ∼0 . 18 ) towards higher ma ( ∼0 . 25 ) at or below the fitted curve ( se = 174 . 74 * ma 2 −47 . 04 * ma + 5 . 8609 , r 2 = 0 . 8363 ) for the theoretical models ( fig . 6 ) . the ma values of models of actual species covered a slightly larger range than predicted by theoretical models , from ∼0 . 16 to ∼0 . 27 ( fig . 6a ) . the exception is the myrmecophagous hyaenid proteles cristata , which has an ma of ∼0 . 12 , lower than all actual species and theoretical models . se values of actual species followed the overall trend predicted by the theoretical models , but do not follow the theoretical pathways exactly . to test for potential differences created by scaling factor , models of actual species were re - analyzed after scaling by total volume , total muscle attachment surface area , or total skull length ( condylobasal length ) . volume - and muscle - scaled models returned essentially identical results as the total surface area method ( fig . 6a ) . scaling by skull length returned similar results , except that ma values for the derived hyaenids crocuta crocuta and parahyaena brunnea were lower , and se values for ictitherium and chasmaporthetes lunensis were also lower ( fig . 6b ) . such differences did not change the overall trends , however .
von mises stress distributions on the actual models showed a general trend of increasingly stressed fronto - parietal regions in hyaenids ( fig . 7a–g ) . the canid models showed no such trend , and in general had moderate levels of von mises stress spread over the dorsal cranium , except for elevated stress levels in canis lupus and decreased levels in epicyon haydeni ( fig . 7h–m ) . the fronto - parietal region in ikelohyaena abronia and canis lupus showed the highest peak stress , and in all models the temporomandibular joints tend to have elevated stress levels ( fig . 7 ) .
the generation of simplified functional landscapes was used to test the hypothesis that convergent morphological evolution in canids and hyaenids can be explained in terms of functional evolution towards more optimal bone - cracking capability . theoretical skull shapes showed a general increase in mechanical advantage ( ma ) with higher d∶l ratios , although the narrower ( lower w∶l ) skulls had largest levels of strain energy ( fig . 3 ) . actual hyaenid and canid species showed a steady climb up the ma landscape , at the same time moving along topological isoclines in se . such a pattern of evolution is consistent with optimization theory ; in this case two functions of the skull , maximizing ma and minimizing se , are optimized by traveling upslope on the ma landscape and moving along topological isoclines on the se landscape ( fig . 4 ) . therefore , the hypothesis that convergent morphologies shared convergent functional capability is supported .
hyaenid and canid models are adjacent to each other on the ma vs . se plots , with more derived species having higher ma ( fig . 6 ) . as predicted by the landscape model , the path from less derived species to more specialized species tend to occur downward ( i . e . smaller se for a given ma ) or rightward ( i . e . larger ma for a given se ) on the plot ( fig . 6 ) . such distribution is expected under an optimization model . the functional correlation of the ma and se distributions is further supported by the fact that proteles cristata , a specialized insectivorous hyaenid , does not crack bones , and accordingly has very low ma towards the bottom left corner of the ma vs . se plot ( fig . 6 ) . this exception also supports the interpretation that there is an adaptive coupling of functional attributes and ecology in this sample of carnivorans .
overall , among the theoretical models used to construct the functional landscape , only a small number overlapped with actual morphologies ( fig . 5 ) . in the upper left and upper right regions high ma is coupled with high se , making those morphologies sub - optimal ; those areas are accordingly not occupied by actual species ( fig . 5 ) . the bottom right corner is marked by both low ma and low se , and is similarly not optimal . the actual path taken by canids and hyaenids constitutes a route of increasing ma at relatively small cost in se increase ( fig . 5 ) . therefore , the functional landscape distributions of actual species predict skull ma to be maximized relative to increase in skull se through evolution . the distribution of ma versus se values for the 13 actual skull models show an intermediate position within the range of theoretical morphologies , overlapping the regions predicted by the functional landscape , therefore supporting theoretical predictions ( fig . 6 ) .
distributions of modern north american and east african carnivoran species on the functional landscapes .
distributions are plotted on the ma ( a ) , se ( b ) , and ma∶se ( c–d ) landscapes . arrows indicate pathways of evolution for hyaenids ( light arrows ) and borophagine canids ( dark arrows ) . species distributions of modern carnivoran species are plotted as solid contours . peaks on the ma∶se landscape ( d ) represent optimized theoretical skull shapes that are either realized ( light shade ) or unoccupied ( dark shade , with question mark ) . ( d ) corresponds with figure 5 .
list of modern north american and east africa carnivoran species used to construct contour of carnivoran distribution .
the extensive overlap of modern carnivorans with the evolutionary sequence of canids and hyaenids indicates constraint in skull shape disparity within the hybrid morphospace of theoretical possible shapes ( fig . 2 ) . presence of such a higher - level constraint created a limitation on the evolution of functionally more optimized skull shapes in bone - cracking carnivorans ( fig . 8 ) . of course , the complex suite of functions that the mammalian skull plays in mastication , food acquisition , and sensory reception meant that constraints on the realized skull shapes are more complex than just biomechanical ones . in the absence of additional non - biomechanical constraints , one optimal path to maximize ma and minimize se would be to travel along topological lines at d∶l between 0 . 3 and 0 . 4 towards higher w∶l ratios ( fig . 8c–d ) . at higher w∶l ratios , se increases more slowly and therefore those shapes have relatively higher ma . in reality , there appears to be a constraint in increasing w∶l ratio across the modern carnivorans analyzed , and consequently skull shape evolved towards higher d∶l with an upper limit of w∶l ∼0 . 7 to instead increase ma on local ( but not global ) optima ( fig . 8 ) .
regardless of the simplicity of a two - dimensional framework , the resulting distribution of actual species on the functional landscape shows a remarkable consistency of maintaining ma∶se ratios throughout the region occupied by bone - cracking canids , hyaenids , and the corresponding modern faunas ( fig . 8 ) . such a pattern indicates an overarching selection for the maintenance of strong skulls and efficient bites across carnivora , attributes which are principal in both active hunting and passive scavenging behaviors . despite the outstanding morphological features of the skull and teeth in specialized bone - cracking ecomorphologies , the functional properties of those derived ecomorphs still operated within the bounds of the carnivoran distribution . again , the notable exception in the modern east african fauna is the cheetah , acinonyx jubatus . skull shape in the cheetah has fallen off the tall ridges on the functional landscape , and is located in a valley with low ma . the strict requirements for speed may have overridden the base functional demands of mastication , demonstrating that such deviation from the major trend is nevertheless feasible ( fig . 8 ) .
among metazoan animals , redundancy in body segments has been proposed to enhance evolutionary potential for differentiation in functions [ 16 ] . an analogous explanation can be applied to the plesiomorphically homodont dentition of vertebrates , which evolved into highly heterodont dentition in mammals . carnivores exhibit fine examples of diversified function of heterodont teeth [ 76 ] . the shallow , slashing bites of pursuit predators are made using the anterior incisors and canines , and the crushing bites of omnivores are made with the posterior bunodont molars [ 77 ] . such differentiation in dental function is shared by all carnivorans on a more general level , indicating the presence of multiple axes of functional properties for different tooth positions alone . carnassial function , the focus of the current study , for example , should be supplemented with study of functional properties in other teeth in order to more fully characterize the potential selective forces that shape craniodental morphology . such integration requires more complex mathematical formulations of a multi - dimensional problem , of which the current study represents a two - dimensional first step that is easily visualized .
in sum , a functional landscape framework constructed from theoretical morphologies showed the presence of functional peaks that are not attained by actual species . the pathways that actual species traversed , however , were nevertheless local optima of relatively high mechanical advantage and moderate skull strain energy . predictions from the functional landscape are supported by results obtained using models of actual species , showing a clear link between form and function in the evolution of bone - cracking ecomorphologies . the restricted region occupied by a wider sampling of modern carnivorans on the functional landscape indicates higher - level phylogenetic constraint as an explanation for the unoccupied optimal peaks . the combination of theoretical morphology and functional modeling with fea has been shown to be an informative approach to test adaptive hypotheses regarding morphological convergence , and has implications for applications in broader taxonomic contexts .
cranium ratio measurements of fossil canids . institutional abbreviations : amnh , american museum of natural history , new york ; f : am , frick collection , american museum of natural history , new york ; hmv , hezheng paleozoology museum , gansu , china ; ivpp , institute of vertebrate paleontology and paleoanthropology , beijing , china ; lacm , natural history museum of los angeles county , california ; mcz , museum of comparative zoology , harvard university , massachusetts ; mvz , museum of vertebrate zoology , university of california , california ; pphm , plains - panhandle museum , texas ; uamz , university of alberta museum of zoology , alberta , canada ; ucmp ; university of california museum of paleontology , berkeley , california . other abbreviations : d∶l , skull depth to length ratio ; w∶l , skull width to length ratio .
cranium ratio measurements of fossil hyaenids and percrocutids . for abbreviations see table s1 legend .
cranium ratio measurements of extant north american carnivorans . for abbreviations see table s1 legend .
cranium ratio measurements of extant east african carnivorans . for abbreviations see table s1 legend .
theoretical models and their parameters . d∶l , skull depth to length ratio ; w∶l , skull width to length ratio ; elements : number of four - noded tetrahedral finite elements in model ; se , skull strain energy ( in joules ) ; adjse , strain energy adjusted by model volume ; fout , output bite force ( in newtons ) ; ma , mechanical advantage ; s . t . , solution time required for fea ( in minutes ) . model files are deposited in dryad ( doi : 10 . 5061 / dryad . r2b1h ) .
finite element model parameters of actual fossil and extant carnivorans analyzed in the study . the number of elements were kept as close to 1 , 000 , 000 elements as possible for both actual and theoretical models . three models had lower counts of elements ( p . brunnea , p . cristata , c . lupus ) , but no correlation of ma or se values to lower element counts was detected . abbreviations as in table s5 . model files are deposited in dryad ( doi : 10 . 5061 / dryad . r2b1h ) .
conceived and designed the experiments : zjt . performed the experiments : zjt . analyzed the data : zjt . contributed reagents / materials / analysis tools : zjt . wrote the paper : zjt .
futuyma dj ( 1997 ) evolutionary biology . sunderland : sinauer associates , inc . 763 p .
mcghee gr jr ( 1980 ) shell form in the biconvex articulate brachiopoda : a geometric analysis . paleobiology 6 : 57–76 .
wright s ( 1932 ) the roles of mutation , inbreeding , crossbreeding and selection in evolution . proceedings of the xi international congress of genetics 1 : 356–366 .
simpson gg ( 1944 ) tempo and mode in evolution . new york : columbia university press . 237 p .
arnold sj ( 2003 ) performance surfaces and adaptive landscapes . integrative and comparative biology 43 : 367–375 .
kauffman sa ( 1995 ) at home in the universe . oxford : oxford university press . 336 p .
thomas rdk , reif w - e ( 1993 ) the skeleton space : a finite set of organic designs . evolution 47 : 341–360 .
mcghee gr , jr . ( 1999 ) theoretical morphology : the concept and its applications . new york : columbia university press . 316 p .
stayton ct ( 2006 ) testing hypotheses of convergence with multivariate data : morphological and functional convergence among herbivorous lizards . evolution 60 : 824–841 .
tseng zj , wang x ( 2011 ) do convergent ecomorphs evolve through convergent morphological pathways ? cranial shape evolution in fossil hyaenids and borophagine canids ( carnivora , mammalia ) . paleobiology 37 : 470–489 .


the l'hoest 's monkey ( cercopithecus lhoesti ) , or mountain monkey , is a guenon found in the upper eastern congo basin .

they mostly live in mountainous forest areas in small , female-dominated groups .

they have a dark coat and can be distinguished by a characteristic white beard .

l ' hoest ' s monkey

( see lhoests monkey management guidelines - guenons - section 1 ( l ' hoest ' s monkey - biology and field data ) for general information ) .
l’hoest’s monkey inhabits forest up to altitudes of 2 , 500 metres ( 2 ) .
no critical habitat rules have been published for the l ' hoest ' s monkey .
there ' s a new arrival at the edinburgh zoo , a baby l ' hoest ' s monkey .
l ' hoest ' s monkey consumes fruits , leaves , seeds , flowers , and arthropods .
( tolo , et al . , 2008 ;
l’hoest’s monkey ( cercopithecus lhoesti )
, 2007 )
( hart , et al . , 2008 ;
l’hoest’s monkey ( cercopithecus lhoesti )
, 2007 )
flannery , s . 2007 .
l ' hoest ' s monkey ( cercopithecus lhoesti )
( on - line ) . the primata . accessed february 22 , 2011 at l ' hoest ' s monkey ( cercopithecus lhoesti ) .
. l ' hoest ' s monkeys are also hunted by humans for bushmeat .
fruits , leaves and invertebrates make up the majority of the l’hoest’s monkeys diet .
the l’hoest’s monkeys have an average lifespan of 30 years when living in captivity .
the l ' hoest ' s monkeys are managed by the european endangered species programme .
little information is available regarding the home range of l ' hoest ' s monkeys .
to the humans , the l’hoest’s monkeys are a source of food in form of bush meat .
( basabose and yamagiwa , 1997 ; mitani , et al . , 2001 ;
l’hoest’s monkey ( cercopithecus lhoesti )
, 2007 )
l ' hoest ' s monkey is found in the countries of burundi , rwanda , uganda , and zaire . this species prefers the montane ,
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. l ' hoest ' s monkeys also have cheek pouches , in which they carry food while foraging .
( see lhoests monkey management guidelines - guenons - section 1 ( l ' hoest ' s monkey - biology and field data ) for general information ) . as in lhoests monkeys , individuals can be seen sitting with their tails intertwined ( hill , 1966 ) . hamlyns monkeys may have a specialised cutaneous glandular area in the sternal region of the chest similar to that found in the de brazzas monkeys ( cercopithecus neglectus ) ( see section 1 . 8 and kingdon , 1988 ) .
the l’hoest’s monkey is classified as a genus cercopithecus member , and it’s closely similar to hamlyn’s monkey ( c . hamlyni ) not only in size , but distribution as well . previously , these l’hoest’s monkeys included the taxon preussi from the gulf - of - guinea area as a subspecies however its currently regarded as a separate species – preuss’s monkey ( c . preussi ) , and this with the sun - tailed monkey ( c . solatus ) , these form the c . lhoesti group .
l ' hoest ' s monkey mother tumbili holds her as - yet unnamed baby , born on sept . 24 , 2012 at the edinburgh zoo in scotland .
this is used as a threat display by the l ' hoest ' s monkey and head bobs up and down ( estes , 1991 ) . this often occurs with
l ' hoest ' s monkey - cercopithecus lhoesti . baby monkey is carried by mummy monkey . filmed at colchester zoo , essex , united kindgom » facebook » urltoken » twitter » urltoken » vimeo » urltoken thanks for watching , subscribe , leave comments and feedback !
after birth , a baby l ' hoest ' s monkey clings to its mother ' s belly while she licks it clean . females in the group try to hold new infants . because social groups are composed of related females and young , parental care likely occurs . young l ' hoest ' s monkeys often entwine their tail with their mother ' s .
, including l ' hoest ' s monkeys . to escape eagles , they flee on the ground , which is uncharacteristic of
( see lhoests monkey management guidelines - guenons - section 1 ( l ' hoest ' s monkey - biology and field data ) for general information ) . the hamlyns monkey is slower in its movements , shyer , and quieter than other guenons ( kingdon , 1980 ) . allen ( 1925 ) suggested that there was some nocturnal activity in these monkeys , though there has since been no evidence put forward to confirm or deny this .
wildscreen . 2007 .
l’hoest’s monkey ( cercopithecus lhoesti )
( on - line ) . arkive images of life on earth . accessed february 22 , 2011 at urltoken .
l’hoest’s monkeys sleep up in the trees in a sitting - position , holding each other or holding the branches of the trees .
when sleeping , l’hoest’s monkeys frequent favourite tree spots , where they sleep as a group , out of reach of many predators . newborn l’hoest’s monkeys are brown and acquire adult colours over the first two to three months . the young are frequently observed entwining their tail with their mother’s ( 2 ) .
( see lhoests monkey management guidelines - guenons - section 1 ( l ' hoest ' s monkey - biology and field data ) for general information ) . the distribution of hamlyns monkey is similar to that of the lhoests monkey ( see earlier and lernould , 1988 ) . its range limit in the north is at the rivers zaire and lualaba , in the west at the rivers lindi and nepoko , in the east at the virungu volcano range , and in the south at rainforest boundaries ( rahm , 1970 ) . the eastern limit is approximately level with lake kivu , while the southern limit is at approximately 4º south ( colyn , 1988 ) .
the sun - tailed monkey was first described in 1986 ( 1 ) . it is a close relative of l’hoest’s monkey , ( cercopithecus lhoesti ) , and preuss’s monkey ( c . preussi ) , and in many ways resembles these primates with their dark grey coats , white markings , and long tails ( 4 ) ( 5 ) .
l’hoest’s monkeys’ lives are threatened by the common chimpanzees which on many occasions have killed the l’hoest . there are also the crowned hawk - eagles which prey on guenons , they do not exclude the l’hoest’s monkeys . so to be able to escape the eagles , they have to flee while on the ground . other predators include the humans who hunt them for bush meat .
l’hoest’s monkeys have a more terrestrial lifestyle compared to most monkeys . they will live in groups with one adult male and form close bonds that are reinforced through mutual grooming . when feeding and sleeping , l’hoest’s monkeys will move higher into the trees and individuals will have favourite sleeping spots .
( see lhoests monkey management guidelines - guenons - section 1 ( l ' hoest ' s monkey - biology and field data ) for general information ) . a number of vocal signals and their social implication have been described by kingdon ( 1988 ) . most notable in hamlyns monkeys is the absence of any high pitched alarm calls . the male rallying call is a deep ' booming ' followed by a series of short explosive ' hacks ' .
the l’hoest’s monkey has a dark brown coat , a dark belly and a chestnut color running across its back . it has light gray colored cheeks and a pale moustache , with an outstanding white bib .
facts - l ' hoest ' s monkey also known as : l ' hoest ' s guenon , mountain monkey french : cercopithèque de l ' hoest kingdom animalia phylum chordata class mammalia order primates family cercopithecidae genus cercopithecus ( 1 ) size male head - body length : 54 - - 70 cm ( 2 ) female head - body length : 45 - - 55 cm ( 2 ) male weight : 6 - - 10 kg ( 2 ) female weight : 3 - - 4 . 5 kg ( 2 )
l ' hoest ' s monkeys are occasionally infected with simian immunodeficiency virus , or siv . when transmitted to humans , this virus becomes hiv .
the range of the l ' hoest ' s monkey is restricted to the albertine rift and a region of lowland forest in eastern d . r . congo . nyungwe is the only location where these typically elusive monkeys have been habituated and studied intensively . as a large forest where l’hoest’s monkeys are widely distributed , nyungwe represents a key location for their conservation .
the zoo also hosts another pair of l ' hoest ' s monkeys , which are native to the democratic republic of congo , rwanda and uganda .
the lifespan of l ' hoest ' s monkeys in the wild is currently unknown . one captive specimen lived to be 24 . 1 years of age .
populations of l’hoest’s monkeys are decreasing due to deforestation from agricultural development and hunting . they are listed as vulnerable on the iucn red list of threatened species .
tolo , c . , j . baranga , g . kagoro - rugunda . 2008 . dietary selection of l’hoest’s monkeys in kalinzu forest reserve , southwestern uganda .
l ' hoest ' s monkey has a unimale social group that occasionally has extra - group males . male competition is high when there are extra - group males . only one male gets to copulate with all of the females .
photographer peterdc8 caught these compelling photos of moto , colchester zoo ' s year - old l ' hoest ' s monkey over the weekend . the name ' moto ' means fire in swahili . as evidenced by these photos of moto eating veggies , the l ' hoest diet is primarily herbivore , although l ' hoests are also known to eat eggs , lizards , and small birds . these charismatic monkeys are listed as vulnerable to extinction by the iucn .
l ' hoest ' s monkeys reside in montane tropical rainforests , including both primary and secondary forests . in secondary forests , they occupy the thick underbrush that grows where trees have fallen . l ' hoest ' s monkeys can be found at altitudes ranging from 900 to 2 , 500 m . the species is typically more terrestrial than other
due to their semi - frugivorous diet , l’hoest’s monkeys play a role in seed dispersal . members of this species are known to host two types of gastrointestinal worm parasites ,
l ' hoest ' s monkeys are considered vulnerable by the icun red list and endangered by the us federal list . populations are decreasing because of deforestation due to agricultural expansion as well as hunting . l ' hoest ' s monkeys were at one point listed in appendix ii by the convention on international trade in endangered species ( cites ) , which means international trade of this species is monitored . however , hunting of this species for bushmeat still occurs . l ' hoest ' s monkeys are most vulnerable to snares and shotgun hunting .
( see lhoests monkey management guidelines - guenons - section 1 ( l ' hoest ' s monkey - biology and field data ) for general information ) . hamlyns monkeys live in single male groups of 10 or fewer ( rahm , 1970 ) . a study on a captive group by peters ( 1992 ) showed relatively high levels of allo - grooming in this species ( 13 - 29 % of their time ) . this indicates a rigidly maintained dominance hierarchy ( see marler , 1965 ) , though no studies have been done to confirm or refute this .
l’hoest monkeys can also live in captivity . at the moment , their life span while in the jungle is not yet unknown however , while in captive , this monkey can live for 24 . 1 years .
i investigated the feeding ecology of l’hoest’s monkeys ( cercopithecus lhoesti ) and blue monkeys ( cercopithecus mitis ) in the kalinzu forest , uganda . although forest guenons are generally thought to be frugivores or folivores , these two guenons spent a large proportion of their time feeding on invertebrates . the l’hoest’s monkey and the blue monkey spent as much as 66 and 50 % of their time on insectivory , respectively . these proportions of time spent on invertebrate feeding are higher than those reported elsewhere for forest guenons . l’hoest’s monkeys mainly utilized the area near the ground for invertebrate feeding , while blue monkeys utilized the area around 20 m above the ground . it seemed that guenons have an ability to change their diet according to the environment .
when our founder , dr . harry wegeforth , went to the east coast and purchased pairs of several species from dealers . our first guenons were lesser spot - nosed monkeys and sykes monkeys received in an exchange with a german zoo in 1929 , and a schmidt’s red - tailed monkey came in 1930 . l’hoest’s and owl - faced monkeys were added to collection in 1960 , with a young pair of the latter as gifts from the leopoldville zoo in what is now the democratic republic of the congo . the san diego zoo was the first facility in the world to welcome a diana monkey birth and the first in the united states to have a l’hoest’s monkey baby .
research support , u . s . gov ' t , non - p . h . s .
female l’hoest ' s monkeys usually give birth every other year at the end of the dry season . on average , females l ' hoest ' s monkeys produce a single offspring after 5 months of gestation . infants are born with their eyes open and fully covered in brown fur . their fur darkens to adult coloration around 2 to 3 months of age . young l ' hoest ' s monkeys nurse until mothers birth another offspring , but frequency of nursing considerably decreases after the first few months . on average , weaning occurs around 1 year of age . when males reach sexual maturity , they leave the group .
the convention on international trade in endangered species ( cites ) lists l’hoest’s monkey on appendix ii , meaning that any international trade in this species should be carefully monitored ( 3 ) , but this does little to control hunting for bushmeat . while this species does occur in some protected areas , such as bwindi impenetrable national park ( 7 ) , these populations still face threats , as mentioned above . while its large distribution and largely inaccessible forest habitat protects the species’ short - term survival , the long - term prospects for the handsome l’hoest’s monkey are not so secure ( 2 ) .
l’hoest’s monkeys are among those really vulnerable primates on the red list of the icun . their populations are currently declining because of a number of factors like deforestation for human activities like settlement , hunting , among others .
adult l ' hoest ' s monkeys typically weigh between 9 to 18 pounds ( 4 and 8 kilograms ) . these primates are endangered in the wild due to deforestation of their habitat and people hunting them for bushmeat .
l’hoest monkeys can also spread diseases to humans because they are sometimes infected with a virus called simian immunodeficiency or siv which changes into hiv when transmitted to human beings .
this species has cheek pouches to carry food in while it forages . the average body mass for an adult male is around 7 . 5 kilograms , and for a female it is around 4 . 3 kilograms . the foot of l ' hoest ' s monkey is quite narrow , more adapted for running on the ground .
the rest of our guenons share their enclosures with other species . for example , wolf’s monkey siblings dru and amara live with two pygmy hippos , elgon and francesca . amara and dru love to hop atop a hippo’s back for a free ride or swim underwater right alongside them , which is unusual for a monkey .
the diet of l ' hoest ' s monkeys consists mainly of fruits , leaves , and invertebrates . invertebrates typically constitute a little less than half of the diet , while fruits and plant materials make up over 50 % . however , in some locations , the dietary percentage of invertebrates is as low as 9 % . l’hoest’s monkeys usually forage for mushrooms , terrestrial herbs , and arthropods in the lower strata of the forest and search the upper strata for small fruits , buds , flowers , young leaves ( which have more protein than mature leaves ) , and herbaceous stems . they often look for arthropods in shallow streams , fallen leaves , trunks , and branches of the forests . l ' hoest ' s monkeys favor fruits of
santiago , m . , f . bibollet - ruche , n . gross - camp , a . majewski , m . masozera , i . munanura , b . kaplin , p . sharp , g . shaw , b . hahn . 2003 . noninvasive detection of simian immunodeficiency virus infection in a wild - living l’hoest’s monkey ( cercopithecus lhoesti ) .
when the mother gives birth , her little l’hoest’s will clings onto its mother’s belly and also the other females in their group will want to hold this newly born infant . this parental care from other group members is probably because of the fact that these social groups usually comprise of blood related females and their young ones .
medway , l . ( 1972 ) . phenology of a tropical rain forest in malaya .
the l’hoest’s monkeys breeds seasonally , and the timing is based on the area they are in . following a gestation period of approximately 5 months , they give birth to one young . it’s typical that they give birth at night and usually at the finish of the dry season , which enables lactation when the rains are heavy .
l ' hoest ' s monkeys are polygynous . a single male lives and mates with many females . when males have reached sexual maturity they leave the group . when females are ready to mate , they direct their hindquarters toward a male , know as presenting .
l’hoest’s monkeys are herbivores , they mainly feed on fruits , leaves , and small invertebrates but they contribute less than half their diet 50 % of their diet consists of fruits and plant materials . they also feed on mushrooms , herbs , and arthropods which they find in the shallow streams , they look for small fruits , fresh young leaves with more protein , buds and flowers as well as herbaceous stems . l’hoest’s monkeys prefer fruits from particular plants . and they feed on particular invertebrates like insects , different ants . earth worms , the spiders and also grasshoppers .
fight black - and - white colobus vs . patas monkey ( singapore zoo ) / бой колобуса с мартышкой - гусаром
l’hoest’s monkeys live in groups with a single male and 10 to 17 females or young , most of which are related . they forage and sleep as a group in trees , and also participate in mutual grooming , which solidifies close bonds within the group . they rarely associate with other
this display by l ' hoest ' s monkey is used as a threat display ( estes , 1991 ) . the eyes are fixed on the stimulus and the eyebrows are raised and the scalp is retracted , the facial skin is also stretched by moving the ears back ( estes , 1991 ) . underneath the eye lids the color is different which contrasts sharply with the surrounding facial color ( estes , 1991 )
height : tallest - patas monkey erythrocebus patas , 19 to 34 inches ( 48 to 87 . 5 centimeters ) , males are taller than females ; shortest - southern talapoin monkey miopithecus talapoin , 10 to 17 inches ( 26 to 45 centimeters )
weight : heaviest - patas monkey , 9 to 29 pounds ( 4 to 13 kilograms ) ; lightest - southern talapoin monkey , 1 . 6 to 2 . 9 pounds ( , 75 to 1 . 3 kilograms ) , females are lighter than males
kaplin , b . a . and moermond , t . c . ( 2000 ) . foraging ecology of the mountain monkey (
one of africa’s most attractive primates , the l’hoest’s monkey possesses a brilliant white ruff that frames its delicate black face . its second most distinctive feature is the deep - set , orange eyes , surrounded by bare skin that is pale violet in adult males . the body and long legs are black with grizzled grey , except for a chestnut coloured ‘saddle’ . the long tail is thick at the base and tapers to a black brush . fully grown males can be twice the weight of females and have a conspicuous bright blue scrotum ( 2 ) .
altmann , s . a . , and altmann , j . ( 1970 ) .
. it is also called the
long - tailed macaque
, and is referred to as the
cynomolgus monkey
in laboratories .
the l’hoest’s monkeys are so polygamous in nature in a way that one male monkey lives and also mates with so many females . the moment a male reaches its sexual maturity , he will have to leave the group and assume independence and at that time , they are looking out for the mature female . the mature females have a signal , once they are really ready to meet the male , they start directing their behind toward the males and this behavior is called presenting .
the l’hoest’s monkeys mainly live in rwanda , northeastern d . r congo , western uganda as well as burundi . it’s a forest monkey that loves dump pristine forests . they can be seen in gallery forest , on forested mountain slopes , mature lowland rainforests , as well as forest borders , nonetheless , they have been seen in cultivated areas . however , it also will live on cultivated lands . in mountainous areas they are commonly seen in mature and twisted undergrowth with broken canopy , and then in lowland forests they are seen in areas where the forest is regenerating .
the l’hoest’s monkey is found in tropical rainforests of africa . it has a white ruff that frames the face with distinctive deep set orange eyes . their bodies are black and have long legs which are grizzled with grey . they have a chestnut coloured “saddle” at the base of their back . their long tails are thick at the base and brush - like towards the end . males can grow to be twice the weight of females and are easily recognised by their bright blue scrotum .
l ' hoest ' s monkeys occassionally flee from predators while on the ground , which necessitates coordination , though the manner of this coordination is unknown . when females are ready to mate , they direct their hindquarters toward a male , know as presenting . l ' hoest ' s monkeys also utilize a variety of behaviors as a threat display . staring involves fixing the eyes on a subject , raising the eyebrows , stretching the facial skin , and moving the ears back . often , they open their mouth but do not display their teeth . additionally , they may engage in head - bobbing , which often occurs with staring with an open mouth , and is also a threat display .
in group of l’hoest’s monkeys , there is usually only 1 male while the females may be 10 – 17 in number and young ones , all of them are often related . they always go hunting for food and to sleep in the trees as a group . as group , they participate in the mutual grooming thereby strengthening their bond between group members . l’hoest seldom interact with the other guenons in the forest . they spend most of their time on the ground and they may also flee from danger like predators while still on the ground rather than climbing up the trees which is a rare character among primates .
cm , and has a black tuft at the end , similar to a lion ' s tail . the male ' s tail - tuft is more developed than that of the female .
the lion - tailed macaque ( macaca silenus ) , or the wanderoo , is an old world monkey endemic to the western ghats of south india .
naughton - treves , l . ( 1998 ) . predicting patterns of crop damage by wildlife around kibale national park , uganda .
howard pc ( 1991 ) nature conservation in uganda’s tropical forest reserves . iucn , gland , switzerland
inhabits hilly primary and secondary moist evergreen forest ( 1 ) ( 2 ) . the sun - tailed monkey is a predominantly terrestrial primate ( 7 ) .
l’hoest’s monkeys are relatively large in size with a dark coat . they have a striking pattern monkeys with quite long limbs and tail . the females can weigh about 3 . 5 kg , while the males are often larger therefore can weigh up to 6 kg . their body is mostly covered by that short dark gray fur and a big chestnut saddle pattern around the back area .
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elon musk ' s plan to rescue trapped thai boys ? a kiddie submarine that looks like a coffin .
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our group of l ' hoest ' s monkeys is made up of male kizizi , who was born here in may 2003 . he has been paired with tumbili our adult female who was born in april 2001 and arrived here in september 2010 from san diego . in november 2013 kizizi and tumbili welcomed the birth of youngster into their family group , a male which keepers have named jamal ( meaning handsome ) .
feldhamer , g . a . , l . c . drickamer , s . h . vessey , and j . f . merritt . 1999 . mammalogy . adaptation , diversity , and ecology . wcb mcgraw - hill , boston . xii + 563pp .
ostro , l . e . t . , young , t . p . , silver , s . c . , and koontz , f . w . ( 1999 ) . a geographic information system ( gis ) method for estimating home range size .
today , the zoo is home to five guenon species . they can be found in various enclosures in the zoo’s lost forest . lesser spot - nosed monkey sassy is diabetic . trained to accept daily insulin shots , she lives with fellow lesser spot - nosed monkeys rachel and lester .
it has been suggested that hamlyns monkeys avoid living in mixed species troops ( gautier - hion , 1988b ) , perhaps because association with another troop would increase the likelihood of a predator detecting the small and inconspicuous troop of hamlyns .
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status : cites - appendix ii ; u . s . esa - endangered ; iucn - lower risk ( nt )
nowak , ronald m . , 1994 . walker ' s bats of the world . johns hopkins university press , baltimore .
after they have mate and the female l’hoest’s monkey has conceived , she will have a gestation period of 5 months after which she will give birth to normally 1 offspring . they mainly give birth towards the end of a dry season every year . at birth , the infants are delivered with eyes open and their bodies are fully covered with that brown fur which only turns dark as they get older , color starts changing when they turn 2 or 3 months old . the mother will nurse its infant until another is born although they stop caring so much about their little ones after some few months . weaning however occurs when the infant is about 1 year old .
mitani , j . c . , sanders , w . j . , lwanga , j . s . and windfelder , t . l . ( 2001 ) predatory behavior of crowned hawk - eagles ( stephanoaetus coronatus ) in kibale national park , uganda . behavioural ecology and sociobiology , 49 : 187 - 195 .
chapman , c . a . , wrangham , r . , and chapman , l . j . ( 1994 ) . indices of habitat - wide fruit abundance in tropical forests .
struhsaker , t . t . ( 1978 ) . food habits of five monkey species in the kibale forest , uganda . in chivers , d . j . and herbert , j . ( eds . ) ,
if you hear a guenon sneeze , it ' s probably the
sneeze call
that guenons pass through the group as an alarm .
team wild , an elite squadron of science superheroes , needs your help ! your mission : protect and conserve the planet’s species and habitats from destruction .
it ' s always exciting to see the babies grow and take their first few swings through the enclosure ,
hughes said in the statement .
carroll , s . b . 2006 . the making of the fittest . new york : w . w . norton and company . isbn 9780393061635 .
guenon babies are weaned at 9 to 18 months , depending on the species . with most guenons , related females stay with each other throughout their lives ; a daughter’s social status depends on her mother’s ranking in the group . males leave their family to join a different group when they reach maturity .
guenon mothers are the main caregivers for their single infant , although other adult females in the group may assist . guenon babies are carried by the mother , and at two weeks of age , babies are able to climb on their own . they attain their adult coloration at two to three months ; the characteristic beard and mustache of de brazza’s monkeys appear at about three weeks . de brazza’s monkey babies grow up faster than those of other guenons ; by the time they’re five months old , they’re already finding and eating their own fruit .
spot - nosed and crowned monkeys also communicate by jerking their head in different positions , each of which mean something specific . de brazza ' s monkeys use their lush , white beard for visual displays . scientists have recorded seven different sounds wolf ' s monkeys make , including a grunting call they use to keep in contact while foraging . it appears that this grunting increases when the wolf’s monkeys are foraging for insects : could this be their favorite food ?
, eds . b . b . smuts , d . l . cheney , r . m . seyfarth , r . w . wrangham , and t . t . struhsaker . university of chicago press .
this monkey has a restricted range and is therefore highly at risk from habitat loss and fragmentation ( 1 ) . while the area of lope is relatively well protected , the foret des abeilles has been opened up to timber exploitation ( 5 ) . as the forests become accessible for logging , the wildlife becomes more susceptible to hunting by locals for meat . in addition , the sun - tailed monkey is semi - terrestrial and so is at risk from being trapped in ground snares ( 5 ) .
gumert , md , fuentes a , jones - engel , l . ( 2011 ) . monkeys on the edge : ecology and management of long - tailed macaques and their interface with humans . cambridge university press .
a uniquely valuable compendium of taxonomic and distributional data on the world ' s living and historically extinct mammalian species . contributors and editors alike deserve the thanks of all
a bit different from most other guenon species , de brazza’s monkeys are often paired for life . among the largest of the guenons , de brazza ' s have a distinctive , beautiful coloration . their body is grayish , with a reddish - brown back and black arms , legs , and tail . their rump is white , and they have a white stripe on their thighs . young de brazza ' s monkeys have a yellow rump , and adult males have a bright blue rump display during mating season ! groups of de brazza ' s have been known to sit completely still for up to five hours and then creep silently away into the forest .
szalay , f . s . , and e . delson . 1979 . evolutionary history of the primates . academic press , new york . xiv + 580 pp .
red - tailed monkeys live with allen’s swamp monkeys and spot - necked otters live in one enclosure , while just across the path you’ll find red - tailed monkeys and with swamp monkeys with red river hogs , a forest buffalo , and a spot - necked otter . there’s never a dull moment in these mixed - species groups !
because the l’hoest’s monkeys need to flee from heir predators from the ground , they need proper coordination for their own safety . in other matters for example when females need to mate , they start directing their behind towards the males for them to see and this is a signal that the males understand . at some point , they do stare and this involves fixing the eyes that single object , they raise eyebrows , stretch their facial skin , and move the ears back . there are times when they open their mouth without displaying their teeth and sometimes they engage in head - bobbing , which goes along with staring the with opening the mouth when threatened .
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thorington , r . w . , jr . , and s . anderson . 1984 . primates . pp . 187 - 216 in anderson , s . and j . k . jones , jr . ( eds ) . orders and families of recent mammals of the world . john wiley and sons , n . y . xii + 686 pp .
the gabonese government declared the sun - tailed monkey as a fully protected species in 1994 ( 5 ) , and it is now considered a flagship species for conservation in gabon ( 2 ) . the future of this species rests with its protection within its range , and of its habitat . it will be important to determine this primate ' s distribution more precisely , and monitor the planned logging operation in the foret des abeilles and lope closely ( 5 ) .
an animal adoption is the perfect gift for all animal lovers . each adoption helps support twycross zoo’s conservation work worldwide , as well as help care for our animals at the zoo .
this monkey likes company ! the average group size is around 40 individuals . these large groups are divided into sub - groups of two to six monkeys that work together foraging for food . the groups ' sleeping sites are usually located near water , and become regular spots and repeatedly used .
however , it is no longer on ‘the world’s 25 most endangered primates’ list , after the international body compiling it determined that the local governments in southern india had acted positively to protect it .
hamlyns monkeys are predated on the ground by leopards ( felis pardus ) and golden cats ( felis aurata ) , which are particularly abundant in parts of eastern zaire ( kingdon , 1980 ) .
la plupart des définitions du français sont proposées par sensegates et comportent un approfondissement avec littré et plusieurs auteurs techniques spécialisés . le dictionnaire des synonymes est surtout dérivé du dictionnaire intégral ( tid ) . l ' encyclopédie française bénéficie de la licence wikipedia ( gnu ) .
hamlyns monkey is a little known species from dense montane and lowland forest habitats ( kingdon , 1980 ) . it is considered a relatively specialised member of the genus ( verheyen , 1962 ) , relying on cryptic semi - terrestrial habits ( kingdon , 1980 ) . it is found in primary lowland rain forest , montane forest up to 2 , 000m , and bamboo forest ( cords , 1987 ) . the only mountain area it occupies is the kivu ridge , west of lake kivu ( colyn , 1988 ) .
molur s , d brandon - jones , w dittus , a . eudey , a . kumar , m . singh , m . m . feeroz , m . chalise , p . priya & s . walker ( 2003 ) . status of south asian primates : conservation assessment and management plan ( c . a . m . p . ) workshop report , 2003 . zoo outreach organization / cbsg - south asia , coimbatore
de solla , s . , bonduriansky , r . , and brooks , r . j . ( 1999 ) . eliminating autocorrelation reduces biological relevance of home range estimates . journal of animal ecology 68 : 221–234 .
brugiere , d . , gautier , j . p . and lahm , s . ( 1998 ) additional data on the distribution of ceropithecus ( lhoesti ) solatus . folia primatologica , 69 : 331 - 336 .
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wu , h . - y . , and lin , y . - s . ( 1993 ) . seasonal variation of the activity and range use patterns of a wild troop of formosan macaque in kenting , taiwan .
this animal has several common names . it is often referred to as the long - tailed macaque because its tail is usually about the same length as its body and because its long tail distinguishes it from most other macaques . the species is also commonly known as the crab - eating macaque because they are often seen foraging beaches for crabs . another common name for m . fascicularis is the cynomolgus monkey , which literally means
dog - milker
monkey ; this is the name most commonly used in laboratory settings . in indonesia , m . fascicularis and other macaque species are known generically as kera , possibly because of the high - pitched alarm calls they give when in danger (
krra ! krra !
) .
, who gave the animal its scientific name in 1821 , did not specify what he meant by the use of this word , although it is presumed it had something to do with his observation of the animal ' s colour .
umapathy , g . ; singh m . , mohnot , s . m . ( 2003 ) .
status and distribution of macaca fascicularis umbrosa in the nicobar islands , india
. international journal of primatology 24 : 281–293 .
information indicates evolutionary relationships at both the ordinal and the family level . this indispensable reference work belongs in public and academic libraries throughout the world and on the shelf of every biologist who works with mammals .
- - publisher ' s website .
guenon ( gwen non ) is the name for a group of medium - sized monkeys that have long back legs , a rounded head , a long tail that helps them balance while moving through the trees , and large cheek pouches . the word guenon comes from the french word for monkey . monkeys in the guenon group are some of the most colorful , graceful , and lively in africa .
, with groups of
outsider
males drifting in and out of the territory . sometimes males live separately or in small bachelor groups . different guenon species often mix together . they understand each other ' s alarm calls and know how to react .
classified as a separate guenon species , allen’s swamp monkeys “go fishing” by laying leaves or grass on top of the water , and grabbing fish that come to hide underneath . as their name implies , swamp monkeys live near water and are good swimmers ; webbed toes help them paddle through water . they have been known to dive into the water to escape predators . allen ' s swamp monkeys have a sturdy build and gray / green skin . the face is reddish with long hair bundles at the cheeks .
depending on subspecies , the body length of the adult monkey is 38 - 55 centimetres ( 15–22 in ) with comparably short arms and legs . the tail is longer than the body , typically 40–65 cm ( 16–26 in ) . males are considerably larger than females , weighing 5 - 9 kilograms ( 11 - 20 lb ) compared to the 3–6 kg ( 7 - 13 lb ) of female individuals .
old world monkeys provide an important ecological role in terrestrial food chains , consuming plant matter ( leaves , fruit , flowers , etc . ) and generally some animals as well ( insects , snails , small vertebrates , etc . ) , and being consumed by large cats ( leopards , tigers , etc . ) , birds of prey , and humans . for humans , these monkeys are popular sightings in the wild or in zoos , and some , such as the rhesus macaque ( macaca mulatta ) , have been used extensively in medical and biological research . the rhesus monkey also has given its name to the rhesus factor , one of the elements of a person ' s blood group .
an old world monkey is any member of the primate family cercopithecidae of the superfamily cercopithecoidea in the clade catarrhini , typically characterized by close - set nostrils that are downward or forward facing , a tubular ear bone , and a tail , if present , that is never prehensile ( adapted for grasping or holding ) . old world monkeys include many of the most familiar species of non - ape primates such as baboons and macaques .
de brazza ' s live in male / female pairs . they have a large
boom
call , made even louder when they inflate their vocal sac , which they use as a warning . the males shake branches to keep a predator away and may even attack !
gumert , md ; kluck , m . , malaivijitnond , s . ( 2009 ) .
the physical characteristics and usage patterns of stone axe and pounding hammers used by long - tailed macaques in the andaman sea region of thailand
. american journal of primatology 71 : 594–608 .
several old world monkeys have anatomical oddities . the colobus monkeys have a stub for a thumb to assist with their arboreal movement . the proboscis monkey has an extraordinary nose while the snub - nosed monkeys have almost no nose at all . the penis of the male mandrill is colored red and the scrotum has a lilac color , while the face also has bright coloration like the genitalia and this develops in only the dominant male of a multi - male group .
wilson and reeder ' s mammal species of the world is the classic reference book on the taxonomic classification and distribution of the more than 5400 species of mammals that exist today . the third edition includes detailed information on nomenclature and , for the first time , common names . each concise entry covers type locality , distribution , synonyms , and major reference sources . the systematic arrangement of information indicates evolutionary relationships at both the ordinal and the family level . this indispensable reference work belongs in public and academic libraries throughout the world and on the shelf of every biologist who works with mammals .
- - publisher ' s website .
guenons use loud , booming calls and bird - like chirps to alert each other . the calls vary depending on the type of predator and its location . the alarm call for the lesser spot - nosed guenon sounds like a car purring ; the male “purrs” to distract the threat while his troop quietly slips away . danger for guenons can come from chimpanzees , leopards , or eagles . hanging out with other monkey species may help all the monkeys improve their diets and be better able to spot predators—safety in numbers !
disclaimer : itis taxonomy is based on the latest scientific consensus available , and is provided as a general reference source for interested parties . however , it is not a legal authority for statutory or regulatory purposes . while every effort has been made to provide the most reliable and up - to - date information available , ultimate legal requirements with respect to species are contained in provisions of treaties to which the united states is a party , wildlife statutes , regulations , and any applicable notices that have been published in the federal register . for further information on u . s . legal requirements with respect to protected taxa , please contact the u . s . fish and wildlife service .
↑ c . groves ,
order primates ,
order monotremata ,
( and select other orders ) . page ( s ) 152 - 178 in d . e . wilson and d . m . reeder , eds . , mammal species of the world , 3rd edition , johns hopkins university press ( 2005 ) . isbn 0801882214 .
- - natureserve explorer is a source for authoritative conservation information on more than 50 , 000 plants , animals and ecological communtities of the u . s and canada . natureserve explorer provides in - depth information on rare and endangered species , but includes common plants and animals too . natureserve explorer is a product of natureserve in collaboration with the natural heritage network .
il s ' agit en 3 minutes de trouver le plus grand nombre de mots possibles de trois lettres et plus dans une grille de 16 lettres . il est aussi possible de jouer avec la grille de 25 cases . les lettres doivent être adjacentes et les mots les plus longs sont les meilleurs . participer au concours et enregistrer votre nom dans la liste de meilleurs joueurs ! jouer
wilson and reeder ' s mammal species of the world is the classic reference book on the taxonomic classification and distribution of the more than 5400 species of mammals that exist today . the third edition includes detailed information on nomenclature and , for the first time , common names . each concise entry covers type locality , distribution , synonyms , and major reference sources . the systematic arrangement of
rahm ( 1970 ) found a difference in the relative length of head - and - body and tail between hamlyns monkeys in the mountain forest of kivu ridge and those in lowland forest . this was not thought to be of any taxonomic significance ( colyn , 1988 ) . measurements available for the c . h . kahuziensis subspecies are given below , and show no evidence of size differences between the sub species .
these colorful guenons have nothing to do with a wolf : they were named after the person who first described them for science . they have a pale forehead and a black stripe above their eyes , stretching from tufted ear to tufted ear . this gives them a rather grim appearance , but they are social . because they also feed on nectar , wolf ' s monkeys serve as pollinators for certain rain forest trees .
old world monkeys , together with apes of the old world , comprise one of the three major informal groups of the biological order primates , the other two groups being prosimians and new world monkeys . together , the new world monkeys and the old world monkeys and apes are considered to be
higher primates ,
or simians ( infraorder similformes ) , while the prosimians ( such as lemurs ) are considered to be the
lower primates .
the term monkey , thus , refers to any simian that is not an ape or any primate that is neither an ape nor a prosimian . in reality , monkeys are not a single coherent group and therefore do not have any particular traits that they all share .
gestation in the old world monkeys lasts between five and seven months . births are usually single , although , as with humans , twin births do also occur from time to time . the young are born relatively well developed , and are able to cling onto their mother ' s fur with their hands from birth . compared with most other mammals , they take a long time to reach sexual maturity , with four to six years being typical of most species .
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mittermeier , r . a . , rylands , a . b . and wilson d . e . 2013 . handbook of the mammals of the world : volume 3 primates . lynx edicions , barcelona .
this species was treated in previous red list assessments ( 1986 to 01 july 2008 ) under the genus cercopithecus , but is now placed under allochrocebus following mittermeier et al . ( 2013 ) . this updated assessment was created to accommodate the taxonomic move from cercopithecus to allochrocebus .
justification : listed as vulnerable as the species has undergone past declines and continues to do so . the entire range of this species is in a region of intense conflict , which has exacerbated the identified threats . it is expected that these declines will continue in the face of ongoing political climates , resulting in an overall population reduction of more than 30 % over a 30 - year time - frame ( given a 10 - year generation period ) .
this species ranges from the eastern democratic republic of the congo ( drc ) , east of the lualaba river through the ituri forest , rwanda and western uganda ( southwest kigezi district and the ruwenzori mountains ) , and south to the itombwe massif . the southern limits are poorly defined . isolated populations occur east of the main block of the range , and include kibale forest national park , kalinzu forest reserve , ruwenzori mountains national park , maramagambo forest reserve and bwindi impenetrable national park ( uganda ) , nyungwe national park ( rwanda ) , virunga and kahuzi - biega national park uplands ( drc ) , and kibira national park ( burundi ; barakabuye
2007 ) . recently also recorded from kahuzi - biega lowlands ( drc ) ( j . hall pers . comm . ) . this species is strongly sympatric with
, especially west of the albertine rift . it is found up to 2 , 900 m asl .
widespread within the lowland block , but only locally common in some areas ( e . g . , the epulu area in the okapi wildlife reserve ) . it is also common in some of the eastern fragments ( e . g . , nyungwe and bwindi , the rumangabo area of the virunga np in drc ) .