bluuebunny/crossref_metadata_2025 huggingface dataset:
Osteocyte lacunae size in the genus Xenopus (Pipidae)
Authors: Reumer Jelle W.F. , Thiébaud Charles-H.
Published: April 2008

The relationship is studied between the volume of osteocyte lacunae and the nuclear DNA content and level of ploidy in the genus Xenopus. The lacunae volume and the DNA content appear strongly correlated. The possible use of this relationship in the study of the evolution of the genus is discussed.
Notes on the biology of Lacerta andreanszkyi (Reptilia: Lacertidae)
Authors: Busack Stephen D.
Published: April 2008

Reported only from three general areas at elevations between 2500-3700 m within the High Atlas Mountains of Marrakech Prefecture, Morocco, Lacerta andreanszkyi appears little studied (Saint Girons, 1953; Pasteur and Bons, 1960; Bons, 1967; Klemmer, 1969). Since Werner's (1929) description of this apparently restricted apecies, nothing has been published regarding its biology. The following limited data concerning population density, biomass, sex ratio, feeding ecology, reproduction, frequency of injury, and thermal environment and response of this elusive species are presented below to partially fill this void.
Density and Seasonal Movements of the Adder (Vipera berus L. 1758) in a Subalpine Environment
Authors: Neumeyer Rainer
Published: April 2008

Within a study area of about 1 km2 in a subalpine dwarf shrub community in the Swiss Alps, 148 adders (Vipera berus) were marked and observed during more than six months in 1981. There was no synchronized prenuptial sloughing of males. They seemed to slough only when they had found a female. After copulation the female was guarded by the male. Adult males sloughed three times, adult females only twice or once a year. Adder density was estimated to be about three adults per hectare. Survival of adults probably surpassed 80% after three years. Displacement rate was higher in foraging adders than in pregnant females. Most neonates stayed near the birth place until hibernation. The median home range was 5.20 ha in adult males and 0.76 ha in reproductive females, when estimated with Jennrich & Turner's (1969) method. The difference was probably due to the increased distances the males travelled during the mating period. After the mating period no difference could be found between adult males and pregnant females, in distances travelled, measured as a straight line. Spacing of home ranges was absent even within sexes. Pregnant females seemed to choose microhabitats more selectively than nonreproductive females. Sites of pregnant females had a more southerly exposure than sites of nonreproductive females.
Coexistence and niche segregation in the newts
Authors: Dolmen Dag
Published: April 2008

The newts Triturus vulgaris and T. cristatus are sympatric over almost the whole of their distributional areas, and they very often share the same breeding-ponds. According to "the competitive exclusion principle", however, no two species occupying the same ecological niche can persist together. Accordingly, within their habitat, the niches of the newts should be different. Studies on their macro- and microhabitat, diel activity, terrestrial seasonality and food, both of adults and larvae, indeed reveal such differences, especially in terrestrial seasonality, microhabitat and food preference. Although the habitat requirements of these newts are much the same, there is a clear resource partitioning between them, and adult T. cristatus also tends to exhibit a narrower niche breadth than does T.vulgaris.
Re-evaluation of the status of Japalura mitsukurii Stejneger 1898 (Reptilia: Agamidae)
Authors: Ota Hidetoshi
Published: April 2008

Morphological and ecological re-investigations revealed that two subspecies of Japalura swinhonis (i.e.,,J. s. mitsukurii andJ. s. formosensis) collectively represent a good species, J. mitsukurii, distinct from J. swinhonis. Taxonomic confusions about these species in the literature are reviewed.
Cycles annuels de la testostéronémie et de la thyroxinémie chez Vipera berus L. (Reptilia: Viperidae) en relation avec le cycle sexuel et l'hivernage
Authors: Fleury François , Naulleau Guy
Published: April 2008

Blood samples were taken in Vipera berus during a five year period. Changes in plasma thyroxine and testosterone levels were examined. Plasma testosterone levels show a marked profile. Highest levels are observed a few weeks after the emergence of hibernation from the end of March till the end of April. These values coincide with the mating period and spring spermiogenesis. Plasma thyroxine levels show also seasonal variations. Low values are observed in winter. Plasma thyroxine levels increase in spring and reach a maximal concentration shortly after the peak of plasma testosterone. A secondary peak is observed at the end of summer.
Growth and age at sexual maturity in common toads (Bufo bufo) from two sites in Southern England
Authors: Reading C.J.
Published: April 2008

Growth and age at sexual maturity in the common toad, Bufo bufo, were investigated at two sites (Portland, Purbeck) in southern England between 1981 and 1985. The body length of males and females spawning for the first time (sexual age = 0) at these sites varied significantly between years, but this variation disappeared in females with a sexual age greater than 0. Male and female toads breeding for the first time at the Purbeck site were both larger and had higher growth rates than those on Portland. No reliable growth rates were obtained for females with a sexual age greater than 0 at either site. Growth was most rapid in males during the first two years following metamorphosis when 56% (Portland) and 71 % (Purbeck) of the total growth in body length occurred. The body length of newly metamorphosed toads at both sites was approximately 8 mm but increased by mid September to 14 mm on Portland and 19 mm at the Purbeck site. The earliest age at which sexual maturity was reached was 3 years for Portland males and 2 years for Purbeck males. No reliable estimates for the age at sexual maturity were obtained for females.
Navigation in breeding-migrating common frogs Rana temporaria: a simple translocation experiment
Authors: Lundberg Per , Elmberg Johan
Published: April 2008

The breeding migration of common frogs was studied during one spring. Frogs displaced during migration navigated successfully towards their breeding pond. Solar and visual cues seemed most important to successful navigation.
Chemisch-analytische und elektrophoretische Untersuchungen an Seren von Uromastyx acanthinurus Bell, 1825 (Sauria: Agamidae)
Authors: Hasl Andreas , Hasl Dora
Published: April 2008

As only little information about the blood chemistry of reptiles is available, a contribution for the establishment of standard values of serum parameters from Uromastyx acanthinurus is given. The sera were tested for their contents of total protein, glucose, triglycerides, cholesterol, uric acid, urea, creatinine, bilirubin, aspartate aminotransferase, alanine aminotransferase, γ-glutamyl-transferase, iron, and calcium. In a countercurrent electrophoresis the serum proteins were separated according to their electrophoretic mobility. Additionally, the molecular masses of the proteins were determined by a discontinuous polyacrylamid gel electrophoresis in the presence of sodiumdodecylsulfate. By means of these techniques the albumin and the 7S-antibodies from the Spiny-tailed lizard sera were characterized.
Reproductive characteristics of the lacertid lizard Lacerta lepida
Authors: Castilla Aurora M. , Bauwens Dirk
Published: April 2008

We report on the reproductive characteristics of the lizard Lacerta lepida from two separate geographic regions in Spain. Lizards from central Spain (L. lepida lepida) mature at an age of 32-33 months. upon attaining a minimum size of 122-148 mm snout-vent-length. One clutch averaging 16.9 eggs is produced annually. We found an inverse correlation between egg and clutch size. Lizards from south-eastern Spain (L. lepida nevadensis) have smaller clutches (mean = 12.3 eggs), composed of relatively large eggs, and some individuals produce more than one clutch per year.
Movement patterns of lacertid lizards: effects of temperature on speed, pauses and gait in Lacerta vivipara
Authors: Avery R.A. , Bond D.J.
Published: April 2008

Lacerta vivipara emerging from their overnight retreat before they had the opportunity to thermorcgulate moved with an alternation of locomotor bursts and pauses. Mean speed during bursts of locomotion fell with decreasing temperature from 3.21 snout-vent lengths (SVL) s-1 at the activity temperature (Tact ∼ 33°C) to 0.15 SVL s-1 at 5°C. Between Tact and 19°C the reduction was small (Q10 = 1.12) and statistically not significant; between 19°C and 5°C the change was very much greater (Q10 = 7.7). The pauses between locomotor bursts increased progressively in duration over the whole range of decreasing temperatures from Tact to 5°C, although the change from Tact to 23°C was not significant. Gait changed progressively from almost simultaneous movement of contralateral diagonal limbs at Tact to independent movement of limbs in the sequence LF, RH, RF, LH at 7°C, with increases in the mean duty factor of individual feet from 0.50 to 0.76 and in the proportion of time for which 3 or 4 feet were in simultaneous contact with the ground from 0 to 0.92.
Systematics of Neotropical gastropod-eating snakes: the dimidiata group of the genus Sibon, with comments on the nebulata group
Authors: Kofron Christopher P.
Published: April 2008

Sibon dimidiata and S. sanniola comprise the dimidiata group of Sibon, and S. nebulata and S. dunni the nebulata group. The species within each group are more closely related to each other than to any other species of Sibon. S. annulata, S. argus and S. longifrenis are placed in the synonymy of S. dimidiata, with no basis for recognition of the nominal subspecies S. dimidiata grandoculis. S. sanniola has two subspecies, the nominate form and S. sanniola neilli. The dimidiata group is distinguished by the shared characteristics of: (1) non-cylindrical body (laterally compressed or bread-loaf shape in cross section); (2) head distinctly wider than neck; (3) protruding eyes of large diameter; (4) vertebral and paravertebral scales not or only scarcely wider than other dorsals; (5) 11-20 maxillary teeth; (6) 20-27 dentary teeth; and (7) 1 or 2 postmental scales. The nebulata group is distinguished by the shared characteristics of: (1) laterally compressed body; (2) head distinctly wider than neck; (3) vertebral scales 1 1/4 -1 1/2 times wider than other dorsals; (4) about 12-17 maxillary teeth; (5) about 18-24 dentary teeth; and (6) absence of a postmental scale.
Disponibilidad y uso de recursos tróficos por Lacerta schreiberi y Podarcis bocagei en simpatría en una localidad de la Cordillera Cantábrica, España
Authors: Domínguez José F. , Salvador Alfredo
Published: April 2008

Food availability and diet composition were examined in sympatric populations of Lacerta schreiberi and Podarcis bocagei at a locality in the Cantabrian mountains (province of León, Spain). Neither species uses trophic resources in proportion to their relative abundance. Extensive overlap in diet composition has been found between P. bocagei and juvenile L. schreiberi. Although both species feed mainly on spiders, juvenile L. schreiberi eat the most abundant and P. bocagei select larger prey sizes. Subadult and adult L. schreiberi select beetles and grasshoppers.
Bioacoustic differentiation in Painted frogs (Discoglossus)
Authors: Glaw Frank , Vences Miguel
Published: April 2008

Advertisement calls of the Discoglossus-species D. pictus, D. sardus, D. galganoi, and D. montalentii were studied. In comparison with all other species, the advertisement call of D. montalentii is completely different. The frequency spectrum displays a harmonic structure and resembles a Bombina-call, while advertisement calls of the other Discoglossus species are mostly unharmonious. D. pictus auritus and D. pictus pictus show a great similarity of call patterns. D. galganoi is characterized by the longest call duration. The call of a red-backed Discoglossus with the vague locality "Sardinia", here named "D. spec.", differed substantially from the calls of D. sardus and any other studied specimen. The complex situation regarding the distribution of different Tyrrhenian Discoglossus phenotypes is discussed in this context.
Proteinvariabilität und Taxonomie des Gran Canaria Skinks Chalcides sexlineatus
Authors: Mayer Werner , Tiedemann Franz
Published: April 2008

Zusammenfassung. 65 Exemplare der Skinkgattung Chalcides von 19 Fundorten auf der Insel Gran Canaria wurden hinsichtlich 11 Genloci elektrophoretisch untersucht. Die Exemplare vom Norden und Südwesten der Insel unterschieden sich in der elektrophoretischen Mobilität von 2 Enzymen, CPK und MDH, konstant voneinander. Von WNW nach OSO zieht sich ein Hybridgütel quer über die Insel. Unser Ergebnis spricht klar für die Annahme einer einzigen Art (Chalcides sexlineatus) mit den Unterarten sexlineatus und bistrialus. Dies steht in ausgezeichneter Übereinstimmung mit den morphometrischen Ergebnissen von Lopez-Jurado und Baez (1985), aber im krassen Gegensatz zur Annahme von 3 unterschiedlichen Arten durch Pasteur et al. (1988). Chalcides pallens wird in die Synonymic von Chalcides sexlineatus bistriatus verwiesen.
Comparative morphology of the adrenal gland in selected species of the genus Podarcis
Authors: Laforgia V. , Varano L. , Capaldo A. , Putti R. , Cavagnuolo A.
Published: April 2008

The morphology of the adrenal gland and relationships between noradrenalin (NA) and adrenalin (A) cells were studied in selected species of the genus Podarcis. As in other previously-studied genera, the morphology of the adrenal gland is not homogeneous, and the species examined can be divided into two groups according to the relationship between chromaffin and steroidogenic tissue. Podarcis taurica and P. hispanica, in which the two tissues are strongly separated, belong to one group. P. wagleriana, P. muralis, P. sicula, P. pelofionnesiaca and P. melisellensis belong to a second group in which dorsal chromaffin ribbons send digitations between the steroidogenic cords. The NA/A cell ratio is higher in species of the first group than in those of the second.
Morphological variation, karyotype and reproduction of the parthenogenetic blind snake, Ramphotyphlops braminus, from the insular region of East Asia and Saipan
Authors: Ota Hidetoshi , Hikida Tsutomu , Matsui Masafumi , Mori Akira , Wynn Addison H.
Published: April 2008

Morphological variation, the karyotype, and reproduction in the parthenogenetic blind snake (Ramphotyphlops braminus) were studied on the basis of a large sample from the Ryukyu Archipelago, Taiwan, and Saipan. Meristic and morphometric characters showed little geographic variation. The numbers of transverse scale rings and vertebrae, each somewhat variable within the sample, were significantly correlated with each other. The karyotype of specimens from the Ryukyu Archipelago and Taiwan consists of 42 chromosomes best interpreted as forming 14 triplets, indicating that R. braminus from this region has a triploid karyotype. Clutch size varied from one to eight, and was significantly correlated with the snout-vent length. From observations of gonads in preserved specimens and from captive breedings, R. braminus begins reproduction after April in the Ryukyu region.
Cytogenetic analysis of the pleurodine turtle Phrynops hogei and its taxonomic implications
Authors: Reed Kent M. , Hanks Brian G. , Bickham John W. , Rhodin Anders G. J. , Greenbaum Ira F. , Mittermeier Russell A. , Fedullo Luiz P.
Published: April 2008

Conventional chromosomal preparations of the Brazilian sidenecked turtle Phrynops hogei indicate the karyotype of this species (diploid number 2n = 58; fundamental number FN = 64) is identical to that reported for other members of the genus. Electron microscopic analysis of whole-cell complements of synaptonemal complexes corroborated the karyotypic description and provided definitive resolution of the acrocentric condition of the microchromosomes. Additionally, this approach provided a continuous sequence of prophase I nuclei which enabled detailed description of chromosomal behavior from leptonema through diakinesis and the sequence of centriolar replication.
The influence of tadpole swimming behaviour on predation by dragonfly nymphs
Authors: Chovanec Andreas
Published: April 2008

This study analyses interspecific differences in anuran tadpole swimming behaviour that could influence vulnerability and therefore prey selection by dragonfly nymphs (Aeshna cyanea). Laboratory experiments showed that Bufo bufo tadpoles were almost continually and slowly in motion, which makes them easy prey for the dragonflies. Hyla arborea tadpoles were also very active and slow in swimming; in contrast to Bufo, however, they showed effective predator avoidance strategies (different habitat preferences, high evasiveness). The predation risk of Rana dalmatina larvae was low because the tadpoles were immobile and benthic, rare movements were made with high speeds. Bombina bombina is intermediate in swimming activity, velocity, and vulnerability.
Mating and oviposition in the hylodine frog Crossodactylus gaudichaudii (Anura: Leptodactylidae)
Authors: Weygoldt Peter , Potsch de Carvalho e Silva Sergio
Published: April 2008

Males of Crossodactylus gaudichaudii call from stream edges, and they regularly dive and excavate oviposition places under stones and rocks. A female ready to spawn visits a male, and both animals dive and dig themselves under a stone to lay eggs. Oviposition takes only 1 to 2 minutes. The male visits the eggs again after the female has left, and afterwards carefully closes and conceals the entrance to the oviposition crevice. After hatching, the larvae remain in their crevice for about 2 more weeks, until they are fully pigmented and able to swim in the current. The implications of the observations are discussed. The behaviour observed is compatible with the idea of hylodine-dendrobatid relationships although not sufficient to support this hypothesis.
Is there a dialect in Pelodytes punctatus from southern Portugal?
Authors: Paillette M. , Oliveira M.E. , Rosa H.D. , Crespo E.G.
Published: April 2008

The mating call of Pelodytes punctatus from Algarve (Southern Portugal) is composed of two multipulsed motives, "a" and "b", lasting about 200 ms. One "a" is followed by two, three or more "b"s giving a sucession of "a-b-b-...". The inner timing in pulse rate acceleration distinguishes each motive. We suggest that the Algarve population has its own dialect, which is different from those of Camargue and Liguria, whose mating calls are longer (about 300 and 400 ms) with a syntax of "a-b" pairs. Pulse rates and durations change with temperature.
Variation in stomach contents of the gecko Ptyodactylus hasselquistii guttatus in relation to sex, age, season and locality
Authors: Perry Gad , Brandeis Michael
Published: April 2008

We examined stomach contents of 77 specimens of Ptyodactylus hasselquistii guttatus (Lacertilia: Gekkonidae) from three locations in Israel. Juveniles took smaller and softer prey items than adults. Males had relatively larger bodies and heads and took fewer, larger and more diverse prey items than did females. Composition of stomach contents varied with collection locality and season, suggesting opportunism. Most of the prey items were small. All 324 food items were invertebrates (65.3% Insecta, 23.8% Arachnida, and 10.9% of other classes). A large proportion of food items were strict ground dwellers, suggesting frequent hunting trips to the ground.
The skink Mabuya ivensii: new records from Zambia and Zaire, and the status of the subspecies septemlineata Laurent 1964 and the genus Lubuya Horton 1972
Authors: Branch W.R. , Haagner G.V.
Published: April 2008

Twenty one specimens of the poorly-known skink Mabuya ivensii Bocage 1879, collected from northwestern Zambia and adjacent Zaire, represent the first records of the species from these countries. Continued recognition of the eastern subspecies M.i. septemlineata Laurent 1964 is not supported. Recognition of a monotypic genus, Lubuya Horton 1972, for ivensii is also rejected. The species shows sexual dimorphism in size, females having a maximum snout-vent length of 148 mm, males reaching only 120 mm SVL.
A new species of Latonia (Anura, Discoglossidae) from the lower Miocene of France
Authors: Hossini Saïda
Published: April 2008

The extinct discoglossid genus Latonia Meyer (1843) was widely distributed in Europa in the Tertiary, and included the largest known discoglossid frogs. Among the characters used by most subsequent authors as diagnostic of this genus, is the presence of dermal sculpturing on certain cranial bones, especially on the maxillae and frontoparietals. The state of this character (presence or absence of sculpture) is unknown in the type species of the genus (Latonia seyfriedi), as well as in some fossils referred to this genus. It is established here that sculpture may be lacking in Latonia; this feature characterizes a new species known from three French localities: Coderet (late Oligocene), Laugnac and "Saint-Gérand-Le-Puy" (early Miocene). Such as feature could correspond to a generic distinction. A revision of the type species is required to redefine the genus Latonia.
Breeding of the toad Bufo verrucosissimus: sexual dimorphism and shifting spawning sites
Authors: Tarkhnishvili David N.
Published: April 2008

The Colchic toad (Bufo verrucosissimus) inhabits wet mountain forests of Caucasia and breeds in small and unstable slow streams and seepage pools. Pair formation usually takes place on land. Amplexing couples search for new breeding sites every year; there is little site fidelity. Active searching for breeding sites is facilititated by the small size of males; the species is highly dimorphic, males having a mean body length of 70-85 mm, females a length of 100-130 mm. If a larger, more permanent water body appears in a region, reproductive tactics change and males wait for females around the pond. These generalizations are supported by data collected from 1989-1993. There was an inverse correlation between body size of females and males in amplexing pairs.
Larval ecology of Rana arvalis: an allopatric island population compared with a sympatric mainland population
Authors: Lardner Björn
Published: April 2008

Rana arvalis has escaped its mainland competitor Rana temporaria on the Baltic island of Gotland. Larvae from mainland and island R. arvalis populations were raised in inter- as well as intraspecific regimes of different densities. Gotlandian larvae had a longer larval period and a lower growth rate than mainland conspecifics at the provided densities. The Gotlandian larvae did not respond more strongly to competition with R. temporaria than mainland larvae, but they seemed to have lost competitive ability in general. When competing with a stronger competitor, this loss of competitive ability in general is predicted to give the same effect as a loss of competitive ability towards that specific species.
Tail morphology related to habitat of varanid lizards and some other reptiles
Authors: Bedford Gavin S. , Christian Keith A.
Published: April 2008

Tail shape, length and texture were recorded from 28 species of varanid lizards as well as several other reptiles that were known to be either semi-aquatic or arboreal. The varanids were described with respect to their tail characteristics and we then looked for relationships between tail characteristics and what is known about the habitats and lifestyles of the species. Semi-aquatic species of all sizes and phylogenetic groups have laterally compressed tails with a tall "fin" comprising the dorsal one-third of the tail. The tails of the large non-aquatic varanids are laterally compressed with a coarse texture. The smaller species in the subgenus Odatria have more diverse tails, and the tail characteristics generally correspond to habitats and lifestyles. The terrestrial species that live under rocks on the soil surface have very coarse, spinous tails. Saxicolous Odattria have long, smooth tails, and arboreal species have coarse tails.
Albumin and mitochondrial DNA evolution: Phylogenetic implications for colubrine snakes (Colubridae: Colubrinae)
Authors: Lopez T.J. , Maxson L.R.
Published: April 2008

Previous molecular analyses of colubrine snake relationships have been based on estimates of amino acid sequence differences in the nuclear-encoded protein, serum albumin. Phylogenetic hypotheses based on albumin data are compared to new trees derived from nucleotide sequence variation in a 307-base pair (bp) region of the mitochondrial cytochrome b gene and a 384-bp region of the mitochondrial gene encoding the 16S ribosomal RNA (rRNA) subunit. There are so many multiple substitutions at degenerate sites in the cytochrome b sequences that little phylogenetic signal remains, leaving major conclusions based on the more informative 16S rRNA sequences. Analyses of the sequence data using both parsimony and genetic distance algorithms are largely congruent with earlier conclusions based on albumin, and corroborate (1) the monophyly of the ratsnakes, (2) the derivation of the ratsnake clade from within the racer lineage, and (3) the monophyly of the Nearctic racer clade (Coluber + Masticophis). The 16S rRNA data provide greater resolution of relationships within the racer lineage than either the cytochrome b or albumin data. The trees based on cytochrome b and 16S rRNA sequences do not support monophyly of the racers, in contrast to the albumin data.
Reproduction of Psammodromus algirus in coastal sandy areas of NE Spain
Authors: Carretero Miguel A. , Llorente Gustavo A.
Published: April 2008

The variation in the reproductive cycle of three populations of the lizard Psammodromus algirus living in coastal sandy areas of NE Spain was analyzed. In contrast with those in continental climates, they showed evidence of reproductive stress: the reproductive season began sooner and was longer. Moreover, body size was smaller and sexual size dimorphism did not arise. Only the end of the breeding period was relatively constant. Nevertheless, these different reproductive traits seem to follow a common trend. In general, no important reproductive differences were found among the three coastal areas. Females laying two clutches have been detected in one locality. Clutch size was correlated with female size. The high phenological plasticity of this species is associated with its wide ecological niche.
Embryonic development of the newt Triturus italicus in relation to temperature
Authors: Tripepi S. , Rossi F. , Peluso G.
Published: April 2008

The embryonic development of Triturus italicus was observed at different temperatures. Normal development occurred between 10°C and 22.5°C. In this range of temperatures an hyperbolic relationship between development time and temperature was confirmed.
Aquatic fungi growing on the spawn of certain amphibians
Authors: Czeczuga B. , Muszyńska E. , Krzemińska A.
Published: April 2008

The mycoflora developing on the spawn of nine species of amphibians was investigated under laboratory conditions. Fifty-two zoosporic fungus species were found to grow on the spawn investigated, including 6 chytridiomycetes, 1 hyphochytriomycete, 44 oomycetes and 1 zygomycete fungus. Out of these 52 species, 23 are known as parasites or necrotrophs of fish. Five fungus species were recorded for the first time from Poland.
A new species of Typhlophis (Serpentes: Anomalepididae) from Bolívar State, Venezuela
Authors: Celsa Señaris J.
Published: April 2008

n. Se describe la segunda especie del género Typhlophis. T. ayarzaguenai sp. nov., para la Serranía de Los Pijiguaos, estado Bolivar, Venezuela. Typhlophis ayarzaguenai se diferencia de T. squamosus principalmente por tener un mayor número total de escamas dorsales (398-418 vs 345), mayor número de escamas alrededor del cuerpo (24 vs 21) y mayor número de escamas cefálicas. Esta nueva especie constituye el primer registro del género Typhlophis para Venezuela.
Lists of European species of amphibians and reptiles: will we soon be reaching "stability"?
Authors: Dubois Alain
Published: April 2008

Zoologists at the end of our century are faced with a strong demand from "society" for "final and definitive" lists of taxon names: such lists are requested in particular by administrations and users of "official lists" of species. This has entailed, even among some professional taxonomists, a strong movement in favour of artificial stability of taxon names and of a replacement of the basic rule of the International Code of Zoological Nomenclature, the rule of priority, by a so-called "rule of common usage". The aim of this paper is to show, taking the example of European anuran amphibians, that this way of posing the question is wrong. The major factor of change in taxon names in zoology is taxonomic research, not nomenclatural grooming. Contrary to what is often believed, even in "well-known" regions like Europe, numerous new species have recently been discovered, in part through the use of new research techniques (electrophoresis, bioacoustics, etc.), but also as a result of better exploration of natural populations: the misleading idea that "the European fauna is well known" has acted as a brake against recognition of new taxa when these were discovered in the field. Name changes due to the mere application of nomenclatural rules are much less numerous than those due to the progress of taxonomic research, and they would be even much less common if zoologists and editors paid more attention to the international rules of nomenclature. We are still far from reaching the "holy grail" of "final lists" of animal faunae, even in Europe, and, rather than trying to comply with this request from "society", zoologists should explain why this goal will not be reached soon, and that the only way to accelerate the movement towards it would be the creation of numerous positions of professional zoologists and the increase of funds afforded to basic zoological research in Europe.
RAPD identification of north European water frogs
Authors: Zeisset Inga , Beebee Trevor J.C.
Published: April 2008

A technique for the identification of north European water frogs (Rana lessonae, R. ridibunda and R. esculenta) based on PCR (polymerase chain reaction)-amplification of DNA using random primers (RAPD) is presented. The method requires very small amounts (< 2 mg) of tissue and reliably distinguished the three types of frogs using samples taken from two widely separate localities (Britain and Poland). In addition, the primers distinguished the DNA of water frogs from that of a brown frog (R. temporaria) and from that of two toad species (Bufo bufo and B. calamita).
The Behaviour of Certain Cardueline F1 Inter-Species Hybrids
Authors: Hinde R.A.
Published: April 2008

1. The behaviour of inter-species hybrids between Carduelis carduelis, Chloris chloris and the domestic Canary was studied. 2. All behaviour patterns which occur in both parent species are unchanged in the hybrids. 3. Behaviour patterns whose form or frequency differs in the parent species, occur in an intermediate condition in the hybrids. 4. Behaviour patterns which occur in one parent species only and which are apparently the result of an evolutionary process in which insignificant intention movements have become stereotyped and exaggerated more in that species than in the other, appear in an intermediate condition in the hybrid. 5. The relation between display components and behaviour tendencies are (qualitatively) unchanged in the hybrids.
"String-Pulling" in Birds. Iii. the Successful Response in Greenfinches and Canaries
Authors: Vince M.A.
Published: April 2008

1. Eighteen greenfinches, of which six were wild trapped adults, five were aviary-reared juveniles and seven were hand-reared juveniles; and also sixteen domestic canaries of which six were adults and ten were juveniles were tested in a "string-pulling" situation. 2. The experiment consisted of (1) a training period when birds were fed repeatedly at the point on a perch where the string and bait were to be suspended; (2) a test period when birds were given up to twelve half-hour trials with the bait suspended on a 4" string; and (3) for those birds which failed in the test period, a period of training in string-pulling. Half the juveniles tested were successful in string-pulling, but none of the adults. 3. Results showed that the finches used more varied methods of pulling up the string than do other species (e.g., tits) which habitually use the feet in feeding. It was also shown that the methods used by juveniles tended to be more varied than those of adults. 4. To this greater variety of behaviour is in part imputed the greater success of the juveniles in the string-pulling situation; this factor is, however, considered to be additional to those previously reported: that juveniles spent a greater proportion of each test trial in responding to the string and/or bait, and a diminished tendency to become extinguished in comparison with adults. 5. The way in which behaviour developed throughout the test trials was adaptive in the sense that activity which was reinforced (e.g., by the movement of the bait following a pull on the string) tended in general to increase at the expense of unreinforced activity. 6. Consideration of individual performances during the test and training trials suggested that the birds showed no evidence of insight into the nature of the experimental situation; success tended to occur intermittently and the improvement in performance was on the whole gradual. This suggested that the performance is closer to "trial-and-error" than to insight learning.
Communal Use of One and the Same Nest By Two Breeding Pairs of the Bengalee 1)
Authors: Masatomi Hiroyuki
Published: April 2008

In the present paper, an example of the communal use of one and the same nest by two "pairs" of the Bengalee, Lonchura striata var. domestica, was described. There was no marked aggressiveness between the pairs. Six eggs laid by the two females were indiscriminately incubated. The eggs did not hatch, but a nestling inserted as replacement for the eggs was normally cared for by every member of the four. Shortly speaking, these birds performed all activities including nest building, incubation, and brooding as an individual of a flock consisting of four birds, rather than as a member of a pair. The availability of only one ready-made nest in the cage was considered one of the most important causes of this curious outcome, in combination with the gentle temperament of the species in general.
Lateral Preferences in Monkeys
Authors: Ettlinger G.
Published: April 2008

Hand preferences have been observed in a group of 48 monkeys. It is found that practice in manipulation increases the proportion of animals showing strong and consistent preferences and reduces the initial predominance of left preferences in this sample of animals to near equality with right. The proportion of animals showing strong and consistent preferences is low during initial somatosensory discrimination testing in the dark. The various kinds of change in preference observed on up to ten consecutive tests are analysed in some detail. Thus a full reversal is common in animals changing from a strong preference, whereas a strengthening of the same preference is common in animals changing from a weak preference. 45% of animals change their preference between the first and second test, but this proportion is progressively reduced, for example to 13% changing between tests 3 and 4. Finally the effects of various neurosurgical procedures on the preferences in 30 animals are tabulated. These comprise frontal, temporal or parietal cortical ablations and also section of one optic tract. Only the latter procedure gives rise to changes in hand preferences. It is concluded that the nature of the sensory control (whether visual or somatosensory, or if visual, whether confined to one half visual field) of a manual manipulation is another major determinant of hand preference.
Telencephalon and Behaviour in Gasterosteus Aculeatus
Authors: Segaar J.
Published: April 2008

The investigation concerns the problem of the function of the Telencephalon in the reproductive behaviour of Gasterosteus aculeatus males. This behaviour involves aggressive, sexual and parental activities whose strength was measured in breeding cycles some weeks or months after small parts of the Telencephalon had been removed and compared with non-operated animals. 1. Removal of the N.n. olfactorii or of the Bulbi olf. does not change the normal behaviour. 2. Removal of one complete Telencephalon-hemisphere also does not change the normal behaviour. 3. Removal of the frontal parts of the Telencephalon, including the olfactory bulbs, produces irreversible modifications in the behaviour in subsequent breeding cycles consisting of 1) significantly low Aggression, 2) Sex activity of significantly short duration and 3) significantly high Parental care. 4. Removal of the bilateral parts of the Telencephalon in a breeding cycle one month after the operation produces broadly the same modifications as after frontal operations, but after two or three months the behaviour can revert to the normal pattern. 5. After a transverse cut between the olfactory bulbs and the commissura anterior the behaviour can revert to normal in as little as one month. In other words these changes are reversible. 6. The recovery of the normal pattern is accompanied by regeneration, but is not proportional to the actual amount of tissue regenerated. It happens that recovery of the normal pattern in some days of the breeding week is accompanied by a modified pattern and a striking antagonism between the tendencies in other days. Since this runs sometimes parallel with apparent total regeneration, sometimes with partial regeneration it is probable, that architectonic structures are involved. 7. The regeneration after lateral operation is histologically visible after 42 days as a thick stratum of neuroblasts in the periphery and after 84 days as delamination of the same kind as can be observed in normal animals, and regeneration of nerve fibres. The Telencephalon of Gasterosteus males is concerned with nest-building behaviour and also with governing the relative balance of aggressive, sexual and parental behaviour. This integration is apparently of survival value, ensuring that the animals do obtain, defend and care for the optimal number of clutches per nest.
Brutpflegeverhalten Und Ontogenese Des Verhaltens Bei Surikaten (Suricata Suricatta Schreb., Viverridae)
Authors: Dücker Gerti
Published: April 2008

I. Zwei im Juli 1959 geborene weibliche Surikaten wurden mit dem Muttertier zusammen 10 Monate lang beobachtet. Das Brutpflegeverhalten des Muttertieres wurde unter besonderer Berücksichtigung des Säugens und der Säugestellungen beschrieben. Bei den Jungsurikaten untersuchte ich die körperliche Entwicklung und das damit zum Teil korrelierte Auftreten der einzelnen Verhaltensweisen. Lautäusserungen, Bewegungsweisen, Nahrungsaufnahme, Körperpflege, Abwehr- und Drohverhalten und Spiele wurden vom ersten Auftreten an bis zur Ausreifung bzw. bis zur Verhaltensnorm der Adulten verfolgt und z.T. durch Beobachtungen am Muttertier ergänzt. 2. Viele Verhaltenskompouenten haben die Surikaten mit andereren Viverriden, so vor allem mit anderen Arten der gleichen Unterfamilie der Herpestinen gemeinsam. So stimmen weitgehend Lautäusserungen, Schlafstellung, Scharrbewegungen, Sich-Strecken und Droh- und Abwehrreaktionen überein. 3. Ein Vergleich mit dem Verhalten anderer Raubtierfamilien lässt eine Verwandt-schaft der Surikaten bzw. der gesamten Herpestinen mit den meist als taxonomisch fernstehend betrachteten Musteliden möglich erscheinen. 4. Bei dem nur in einer kurzen jugendperiode auftretenden Zuscharren einer Grube (vielleicht ebenfalls bei dem auch bei Adulten erhalten bleibendem Ausscharren einer Grube vor dem Koten) handelt es sich wahrscheinlich um ein Instinktrudiment.
Parental Behavior and Imprinting in Cichlid Fishes
Authors: Greenberg Bernard
Published: April 2008

The brooding cycles of Hemichromis bimaculatus and Aequidens portalegrensis are very similar in timing except that the latter have a longer pit young stage. Exchanges of eggs or wrigglers between the two species resulted in ready acceptance of foreign young. Experienced as well as inexperienced pairs raised foreign spawn successfully in alternation with their own or were induced to brood mixed schools. Acceptance of eggs, wrigglers or free-swimming young was limited to those individuals, regardless of species, which matched in age and behavior the parents' brooding phase. Therefore, it is concluded that parent H. bimaculatus and A. portalegrensis are not imprinted on the species characteristic of their first or subsequent young. Instead, there appears to be an internal mechanism regulating the duration of the phases of parental care, that limits the responsiveness of the parents to particular stages of young.
Incubation and Nest-Building Behaviour of Black-Headed Gulls Iv: Nest-Building in the Laying and Incubation Periods
Authors: Beer C.G.
Published: April 2008

(I) Data are presented on the kinds and amounts of nest-building responses that occurred in the different situations I observed in the laying and incubation periods. (2) With a few exceptions all situations in which an alteration in some condition produced change in the frequency of rising and settling also produced change in the same direction in the frequency of sideways-buildings and vice versa. On the other hand the numbers of collecting trips were not significantly altered by any of the changes which produced alterations in settling and sideways-building. (3) In most of the samples of watches settling and sideways-building were significantly positively correlated and performance of one response tended to be closely preceded or followed by performance of the other. There was virtually no correlation or temporal association between these two responses and collecting. (4) The majority of collecting trips were performed when partners were together on the territory. Situations which produced extreme increase in rising and settling produced a small number of collecting trips by gulls alone on the territory. Settling and sideways-building were by no means confined to situations when the mate was present although presence of the mate increased the quantity of these responses. (5) It is argued that the term 'displacement activity' is not helpful, and indeed misleads, when applied to the nest-building of Black-headed Gulls in the incubation period.
Facial Expression in Primates With Remarks On a Parallel Development in Certain Carnivores (a Preliminary Report On Work in Progress)
Authors: Bolwig Niels
Published: April 2008

In this report of an unfinished study of the evolution of facial expressions the author draws a brief comparison between the most important facial muscles of various primates and of two carnivores, the suricate and the dog. Before discussing the expressions, definitions of the various elementary emotions are given and the criteria from which the author judges the emotional condition of the animals. The main conclusions reached from the observations are:- 1. Certain basic rules govern the facial expressions of the animals studied. 2. Joy and happiness are expressed by a general lifting of the face and a tightening of the upper lip. The expression originates from preparation for a play-bite. The posture has become completely ritualised in man. 3. Unhappiness expresses itself by a lowering of the face. In horror there is a general tension of the facial muscles and the mouth tends to open while the animal screams. In sadness the animal tends to become less active. 4. Anger is recognisable from a tightening of the facial muscles, particularly those around the mouth in preparation for a hard bite. 5. Threat varies in expression but it contains components of anger and fear. 6. Love and affection find expression through such actions as lipsmacking, love-biting, sucking and kissing. The oral caressing has its origin in the juvenile sucking for comfort. 7. Concentration is not an emotion but it usually shows itself by a tension of the facial muscles. 8. There is a similarity between the two carnivores under discussion and some of the primates. A common pattern of the facial muscles of the suricate and the lemur indicate a common ancestry and brings the two animals to the same level in their ability to express their emotions. The dog, although very different from the monkey in its facial musculature nevertheless resembles it in its mode of expression. This feature seems related to similarities in their biology which have been facilitated by the development of a bifocal vision.
Change in the Response of Spiders To Repeated Web Vibrations
Authors: Szlep Rasza
Published: April 2008

1. The resting position and response to vibrations differ in Arancidae and Uloboridae according to the consistency of the spiral thread. 2. Repeated rhythmic recurrence of the vibration stimulus brings about waning of the response. 3. Response decrement to vibrations of the web is not caused by motor fatigue. 4. The process of response waning is gradual. During the first phase, a slowing down of the response takes place; during the later phase, partial activities disappear and, finally, the responses wane completely. Response waning shows fluctuations. 5. Displacement activities and short latencies of the released responses during the phase of response decrement indicate a high level of sensitivity to vibrations. 6. Renewed release of the response after changing the vibration place proves that the extinction was not caused by adaptation of the receptors to a given vibration intensity. 7. Delayed returns to the hub, delayed responses, turns in the direction opposite to the vibrating radius, returns to the resting position before removal of the vibrating needle, and release of incomplete responses at short latency periods suggest the appearance of inhibiting impulses. 8. The recovery level after a 24-hour interval decreases during successive days of the experiment, independently of the number of tests. 9. Changes in the rate of response decrement and in the recovery level on successive days of the experiment indicate the preservation of long-lasting representations from one day to the next. 10. Rise of the threshold level causes weakening and slowing down of the response, while the appearance of inhibiting impulses brings about waning of the response to vibrations.
Hearing and Responses To Calls in Anurans
Authors: Schmidt Robert S.
Published: April 2008

1. Nerve responses evoked by tone pips of known frequency were recorded from the medulla of Bufo americanus, Rana pipiens, Rana clamitans, Pseudacris triseriata, and Hyla crucifer. 2. Nerve responses were obtained between 20 cps and 4000 cps in Bufo and Rana, and between 100 cps and 6000 cps in Pseudacris and Hyla. 3. In all species, the best frequency for nerve responses was 1000 cps. In Pseudacris and Hyla there was a second low threshold area at 2000-3000 cps. It is suggested that the lower frequency dip in the response curve may represent responses from the pars amphibiorum and that the higher frequency dip may represent responses from the pars basilaris. 4. The threshold at the best frequency in Rana is similar to the sensitivity of human hearing. 5. Three Pseudacris and one Hyla were induced to answer tone pips. 6. These answered pips of frequencies between 700 cps and 4600 cps. Since this conforms to the high frequency dip in the nerve response curve, it is suggested that the Hylids might have been hearing pips with the pars basilaris only. 7. Pseudacris answered pips of a great variety of durations and intervals. 8. The data suggest that responses of Pseudacris males to frog calls may be, to a great extent, non-specific. 9. Alternating of calls in duets is controlled by at least two factors. There is a constant latency between a call and the stimulus eliciting it. A stimulus following a call too closely inhibits calling. 10. The data obtained here and by others suggest that even for location of males by females, the repetitive nature and frequency of calls may be of only minor importance. Rather, trill rate is implicated as an important call parameter.