bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oviposition site selection in three species of European Newts (Salamandridae) genus Triturus
Authors: Miaud Claude 
Published: April 2008

AbstractOviposition site selection in Triturus helveticus, T. alpestris and T. cristatus was studied both in natural and laboratory situations. In a natural breeding site, eggs of the three species were not laid equally on several plants: T. cristatus laid practically all their egges on only one plant (Nasturtium officinale) while T. helveticus eggs were collected on four plant species. In laboratory experiments, plastic and cotton fabric supports made it possible to test ovipositing female selectivity according to flexibility and shape of support and egg-laying distance below the surface. In all three species, a high proportion of eggs were laid on supports of linear shape (as opposed to arborescent shape) and egg frequency decreased as a function of depth (from 0 to 40 cm below the surface). Selection according to flexibility was also observed, the smallest species (T. helveticus) laying more eggs on the thinner supports. The role of support selectivity during oviposition in Triturus is discussed, in term of proximate (i.e. female protection against predators, breathing necessity) and ultimate (i.e. egg survival) factors, and related to new ecology.
Evidence from tooth surface morphology for a posterior maxillary origin of the proteroglyph fang
Authors: Jackson Kate , Fritts Thomas H. 
Published: April 2008

Abstract
Although the front-fanged venom delivery system of the Elapidae is believed to be derived from an aglyphous or opisthoglyphous colubroid ancestor, opinion is divided as to the end of the maxilla on which the proteroglyph fang originated. This study was undertaken to determine whether the evolutionary precursor of the proteroglyph fang was (a) a grooved posterior fang which migrated anteriorly, or (b) an enlarged anterior tooth which secondarily developed a groove for the conduction of venom. The surface morphology of the maxillary teeth of colubrid genera was examined using scanning electron microscopy. Ridges present on the lingual and labial surfaces of anterior maxillary teeth and on the anterior and posterior surfaces of posterior maxillary teeth were identified as morphological markers of potential value in distinguishing the anterior and posterior maxillary teeth of colubrid snakes, and in determining the origin of the proteroglyph fang. Patterns of ridges on the surfaces of elapid fangs examined were found to be consistent with the hypothesis that the evolutionary precursor of the proteroglyph fang was an opisthoglyph fang which migrated anteriorly.
A review of the Usambara forest snake Geodipsas vauerocegae and the Uluguru forest snake G. procterae
Authors: Rasmussen Jens B. , Howell Kim M. , Andersen Mogens 
Published: April 2008

Abstract
Variation in external and internal characters of the endemic Tanzanian species Geodipsas vauerocegae and G. procterae have been examined. On the basis of the small sample sizes, no significant geographical differences can be demonstrated. Three recently collected specimens from the Udzungwa Mountains, however, seem to have slightly lower numbers of ventrals than those from the Uluguru Mountains. All available knowledge on the natural history of the species has been summarized.
Cranial ossification in the northern alligator lizard, Elgaria coerulea (Squamata, Anguidae)
Authors: Good David A. 
Published: April 2008

AbstractAn analysis of patterns of ontogenetic ossification of cranial elements in the northern alligator lizard, Elgaria coerulea, was conducted and those patterns are described here both from the point of view of individual elements and from the point of view of the overall pattern of ossification of the skull. Ossification in Elgaria is then compared with patterns in other squamates.
Differential testosterone sensitivity of forelimb muscles of male leopard frogs, Rana pipiens: test of a model system
Authors: Blackburn D.G. , Darrell R.S. , Lonergan K.T. , Mancini R.P. , Sidor C.A. 
Published: April 2008

Abstract
Certain forelimb muscles of anurans exhibit sexual dimorphism in mass and fiber composition, offering potential for studies of the effects of hormones on muscle characteristics. Androgen-responsiveness of major forelimb muscles of male leopard frogs, Rana pipiens, was evaluated by quantifying the effects of testosterone cypionate administration and castration on lyophilized muscle mass. The coracoradialis, pectoralis epicoracoideus, and pectoralis sternalis muscles were highly-responsive to testosterone treatment, showing a mean dry mass increase of approximately 50% over control values. However, the pectoralis abdominis muscle was unaffected by testosterone administration, and castration had no effect on any of the muscles. Testosterone sensitivity reflects both the degree of sexual dimorphism and the inferred functional roles of the muscles. Because their forelimb muscles vary markedly in androgen-sensitivity, leopard frogs show considerable promise as a model system for clarifying hormonal regulation of muscle characteristics.
Further investigations on Discoglossus bioacoustics
Authors: Vences Miguel , Glaw Frank 
Published: April 2008

AbstractAdvertisement calls of Discoglossus galganoi jeanneae from two localities in southern Spain and D. pictus scovazzi from Ceuta were analyzed. Call duration as well as ratio of pulse group intensities and durations clearly group D. pictus scovazzi with the other subspecies of D. pictus (pictus and auritus). The calls of the taxon jeanneae show some differences to calls of populations of D. g. galganoi from northern Spain, but are more similar to calls of D. g. galganoi than to those of D. pictus scovazzi. These data support the status of jeanneae as subspecies of galganoi.
Divergent male androgen patterns in two sympatric species of Leptodactylus from subtropical South America
Authors: Cei J.M. , Ibanez N. , Alvarez B.B. , Carnevali O. , Mosconi G. , Polzonetti-Magni A.M. 
Published: April 2008

AbstractLeptodactylus ocellatus L. is sympatric with L. chaquensis Cei on the banks of the Parana river, yet does not show evident gametogenic discontinuity or cyclical variation of secondary sex characters compared with the striking and well-defined seasonal rhythm found in L. chaquensis. The endocrine mechanisms regulating the seasonal reproductive cycle in the male of both species in their sympatric area have been studied through assessment of plasma androgens, related to the morphological examination of testis. A sudden intense spermatogenic activity was recorded in the testes of L. chaquensis in spring months (September-October), but this ceased in late November, and was followed by a strikingly long summer rest. Conversely, few morphological changes in L. ocellatus were found, since the mating period is more irregular and extensive. The androgen plasma changes paralleled the morphological observations. The plasma androgens behaved differently in the two species, since in L. chaquensis the androgen peak values occurred at the end of the intense spermatogenic activity, accompanied by dramatic increase of testicular weight and spermiation, while in L. ocellatus, the highest androgen plasma levels, occurring in August, seemed to indicate a precocious reproductive activity in this species. These data are discussed, in view of the pivotal role played by androgens in regulating the discontinuous reproductive cycle of L. chaquensis.
Advertisement call variation in the Leptodactylus mystaceus species complex (Amphibia: Leptodactylidae) with a description of a new sibling species
Authors: Heyer W. Ronald , García-Lopez José M. , Cardoso Adao J. 
Published: April 2008

Abstract
Whereas morphological analysis of populations recognized as Leptodactylus mystaceus indicates there is one species with modest geographic variation, analysis of advertisement calls indicates there are at least two or perhaps three species involved. The differences found in advertisement calls are sufficient to act as species isolating barriers to recognize at least two species, which action is taken. A consequent result is the description of a new sibling species. The significance of sibling species in the genus Leptodacytylus is discussed briefly.
Comparative life histories of a low- and a high-elevation population of the common frog Rana temporaria
Authors: Ryser Jan 
Published: April 2008

AbstractCommon frogs from a breeding pond in the Swiss Alps (1930 m) were studied by skeletochronology and life history traits were compared to a previously described lowland population. Snout-vent lengths ranged from 63 to 85 mm (males) and 65 to 94 mm (females). Ages varied from 4 to 13 years with means of 6.6 (males) and 8.3 years (females). Growth of immature frogs was slow. Immature males grew faster than females, but the reverse was true for adult frogs. Egg numbers ranged from 784 to 1616 and were not correlated with snout-vent length. Egg diameters (1.83-2.19 mm) were positively correlated with snout-vent length. Frogs from the Alps differed from the lowland population in slower growth to maturation, resulting in higher ages, but similar sizes, at first reproduction. I argue that the alpine life history pattern was shaped by two environmentally determined traits, slow growth and high annual survival.
Allozyme variation in populations of Lacerta raddei and Lacerta nairensis (Sauria: Lacertidae) from Armenia
Authors: Bobyn Michèle L. , Darevsky Ilya S. , Kupriyanova Larissa A. , MacCulloch Ross D. , Upton Darlene E. , Danielyan Felix D. , Murphy Robert W. 
Published: April 2008

Abstract
Lacertca raddei and Lacerta nairensis have been recognized as two separate species based on morphology and behavior, and each has been implicated as a sexual parent of different parthenogenetic forms. However, recent mitochondrial DNA work failed to distinguish these two as separate species. We examined genetic diversity at 36 allozyme loci from six populations of L. nairensis and four populations of L. raddei. There were no fixed allelic differences between the two. Mean heterozygosity was slightly higher among populations of L. raddei than among populations of L. nairensis. A Distance Wagner phenogram showed that the northernmost population of L. raddei clustered with the L. nairensis populations; the other L. raddei populations clustered together. We suggest that L. raddei and L. nairensis may not be separate species, a finding which has important implications for determining the origins of some parthenogenetic Lacerta.
Vocalisation and larval transportation of male Colostethus subpunctatus (Anura: Dendrobatidae)
Authors: Fandiño María Claudia , Lüddecke Horst , Amézquita Adolfo 
Published: April 2008

Abstract
We studied calling activity, tadpole transportation and deposition of Colostethus subpunctatus males in the high mountains of Colombia. Calling as well as tadpole transportation and deposition occurred during daylight and night hours. The reproductive activity was found to be well adjusted to rainfall pattern. Males began to call before the start of the rainy season, but tadpole transportation coincided with the first heavy rains when small puddles used for tadpole deposition remained filled. Reproductive activity ceased soon after the period of heavy rains. The number of tadpoles on the back of individual males encountered in the field was highly variable because tadpoles leave the male's back one after another and not all in the same puddle. Some possible functions of this behaviour are discussed. An understanding of the relationships between parental care patterns in the genus Colostethus may be achieved by considering their physiological and behavioural components.
On the Stridulation of Scorpions
Authors: Alexander Anne J. 
Published: April 2008

Abstract1. The stridulation of the scorpions Opisthopthalmus latimanus and O. nitidiceps is described; one of the two mechanisms previously suggested for sound production is shown to contribute almost nothing to the noise. An examination of the responses of a number of small mammals to the stridulation suggests that its biological significance is that of a threat. 2. The caudal stridulation of Parabuthus planicauda is described and it is suggested that it may have arisen from an intention movement of stinging. 3. Reports of stridulation in other genera are examined and it is concluded that the stridulatory movements of scorpions may, in general, be regarded as elaborated from intention movements or displacement activities associated with threat.
Spawning and Parental Behavior in Female Pairs of the Jewel Fish, Hemichromis Bimaculatus Gill
Authors: Greenberg Bernard 
Published: April 2008

AbstractSeven homosexual female pairs were observed on 17 occasions in a total of 22 spawnings. On six occasions the paired females spawned together. Four of the pairs synchronized so well in laying that they deposited rows of eggs alternately or simultaneously on the same site. In fifteen of the spawnings, the behavior of the "partner" of the first spawning female could be summarized as follows: seven ate the eggs and did not spawn until 3.5 days later; three ate eggs but spawned the same day ; three skimmed (or fanned) but did not spawn until 5 or more days later; and two skimmed (or fanned) and then spawned 10 and 45 minutes later, respectively. Hence the partners regarded the eggs as food (majority) or as offspring (minority). None of the partners could be regarded as showing male behavior since their skimming did not resemble the fertilizing movements of the male, except when both laid eggs. Pair formation depended on willingness of the females to inhibit their attacks on each other and to co-operate while maintaining a territory. Responses that seemed to check aggressiveness in the pair mate included the "estrous stance" and quivering. Homosexual groups that did not inhibit aggressiveness developed hierarchies and partial territories instead of pairs. On 11 of the 17 occasions of spawning, both females fanned the eggs and exhibited other parental behavior similar to that of heterosexual pairs. Twice, succcessful exchanges were made for fertilized spawn of Acquidens portalegrensis. These two pairs raised the young competently for 18 and 21 days, respectively, or fully as long as the heterosexual pairs maintained their young under our experimental conditions. It is concluded that female pairs of H. bimaculatus spawn in accordance with the chance synchronization of their separate estrous cycles, although some acceleration or inhibition of the cycle of the partner may result from the activities of the first to spawn. Since bisexual behavior could not be demonstrated, it appears likely that cichlid species performing the Hemichromis type of courtship have only one neuromuscular mechanism that with slight modifications is used by both sexes.
Incubation and Nest Building Behaviour of Black-Headed Gulls. I: Incubation Behaviour in the Incubation Period
Authors: Beer C.G. 
Published: April 2008

AbstractI. Descriptions are given of the elements of the behaviour performed by Black-headed Gulls on the nest during the time between laying of the third egg and hatching of the first egg. 2. With three eggs in the nest it is found that the majority of settling sequences are complete, the majority of sitting spells are relatively long, and the eggs are covered for almost all of the available time. Also most of the relatively long sitting spells are preceded by complete settling sequences and most of the short sitting spells are preceded by incomplete settling sequences; most of the complete settling sequences lead to long sitting spells and most of the incomplete settling sequences lead to short sitting spells. 3. The frequency of settling, the proportion of complete settling sequences, and the total amount of time spent sitting, are used in comparing the behaviour in different situations. It is found that more or less than three eggs in the nest, eggs of abnormal shape or size, fixed eggs, disturbed nest material, scaring stimuli near the nest, presence of the mate, and the early stage of the sitting bout, produce incubation behaviour which differs from the standard pattern; the birds rise and settle more often, spend less total time sitting, and, with the exception of the last two cases, complete less of their settling sequences. On the other hand different times of day, different stages of the incubation period, differences in weather conditions, eggs of abnormal colour or markings were not associated with differences in the incubation pattern in my observations. 4. It is concluded that stimuli relayed from the brood-patches are particularly important in determining the pattern of settling and sitting behaviour. 5. Some problems connected with the use of the concepts of incubation "drive" and incubation "tendency" are discussed. 6. Stimuli to the feet and legs probably play a part in the release of shifting. 7. Quivering while sitting is probably stimulated by disturbed or "novel" contact between brood-patches and eggs.
Exploratory Behaviour in the Short-Tailed Vole Microtus Agrestis
Authors: Shillito Elizabeth E. 
Published: April 2008

AbstractShort-tailed voles know the area of their range in detail and this knowledge is maintained by regular exploratory activity, which occurs at frequent intervals in familiar surroundings as well as in new situations. Observations of this behaviour in voles, suggest that is is an instinctive behaviour pattern. There is an exploratory drive present for the animal to know the topography of its surroundings. The appetitive phase of the drive, called reconnaissance behaviour, takes the form of more or less random movements through the range, during which the animal reacts to anything different from that previously experienced and confirms old objects, so that memory is refreshed. The presence of a "new object" elicits investigation which may follow a set pattern. In the vole this is approach, nose and touch with withdrawals at some stage. The drive is satisfied by reception of sensory stimuli from objects or situations after a certain time of exposure to them. The periodic recurrence of reconnaissance behaviour is believed to be due to a fading of the effects of the sensory stimuli on the animal.
Observations On the Mental and Manipulative Abilities of a Captive Baboon (Papio Doguera)
Authors: Bolwig Niels 
Published: April 2008

AbstractThe present paper is a description of the various performances of a baboon, and how it learned to solve various problems. 1. The animal noticed when strings were not connected with the bait or interrupted. In its choice it was not appreciably disturbed by strings crossing the correct one. 2. Sticks were favourite tools for raking in food. They were also balanced on end while the animal climbed up them to reach overhead bait. 3. If the stick available was not long enough to rake in some food it was used for raking in a longer stick which could be used to get the food. 4. The animal learned, after a few trials, to push one end of a bar to one side to receive food from the other end of the bar. It also learned, without difficulty, to drop a stone into a "slot machine" to obtain food. 5. A case is described in which the animal apparently deliberately set a banana swinging in a certain direction by throwing sticks at it. Having got it swinging it tried to reach it from an upright pipe. 6. It was found that practically all performances and solutions of problems were based on a very small innate repertoire of behaviour and that the manipulative abilities were very limited due to the anatomical structure of arm and hand. 7. Actions not conforming with the innate repertoire could in most cases be learned with difficulty only, or not at all. 8. The animal was able to combine two actions learned separately into one sequence to solve a problem. 9. The ability to manipulate sticks and use them as tools is not innate but a result of learning. The animal becomes familiar with the possibilities of sticks during its play with them.
Behavioural Effects of Electrical Stimulation in the Forebrain of the Pigeon
Authors: Akerman Bengt 
Published: April 2008

AbstractActions belonging to the reproductive behaviour have been released by means of electrical stimulation in the forebrain of unanaesthetized, freely moving pigeons (Columba livia). The following behaviour items, which normally are closely associated with courtship behaviour, were obtained: the bowing action, preening movements - particularly displacement preening, the pecking and the nest demonstration. The different actions were released both in females and males but the aggressive bowing action was induced in considerably more males than females while the nest demonstration was observed in a higher frequency in the females. The positive sites of stimulation were concentrated in the preoptic nuclear complex. Solitary active points were located in nuclei bordering the preoptic area, such as the anterior hypothalamic, the anterior diencephalic paraventricular and the septal. The active zone bordered and partially overlapped the substrate for actions belonging to other categories of instinctive behaviour such as food and water intake and defence and escape. The rather restricted field for courtship actions extended medially up into the paleo-, neo- and hyperstriatum. The responses from the striatal level were generally less complete and intense than those from the more basal level. Stimulation in males at the preoptic and anterior hypothalamic level generally induced an intense bowing action with all normal components, and confrontation with adequate external stimuli released a complete aggressive action. The bowing could also be transformed into nest demonstration via displacement preening indicating a change in motivation from aggressiveness to sexual, which is a clear parallel to the introductory male courtship behaviour. The females also showed parallels to the precopulatory behaviour. The induced response was nest demonstration, preening movements - mainly displacement preening and pecking. The results show that in birds, as in mammals, it is mainly the preoptic area which takes part in the regulation of actions serving reproduction. Evidence has been produced that in birds striatal areas of the telencephalon are also involved in the coordination of such actions. The principle of organisation that can be traced in these experiments shows some interesting similarities to basic elements of animal behaviour and in a broad sense with the principles of the organisation of instinctive behaviour patterns according to TINBERGEN (1951).
Celestial Orientation of Fowler's Toad b uFo Fowleri
Authors: Ferguson Denzel E. , Landreth Hobart F. 
Published: April 2008

Abstract
Young Fowler's toads from on and near the shores of a lake were tested in a circular pen 60 feet in diameter. Under a variety of conditions (e.g. including group tests, individual tests, simultaneous testing of two groups from different shores, long distance displacement, and transit to the test pen both in view of the sky and in lightproof containers), the toads oriented under the sun to a compass direction (Y-axis) corresponding to a line bisecting the home shoreline at right angles. This orientation persisted after 72 hours in darkness, indicating the existence of an internal clock mechanism. Reorientation to a new shore was evident in 24 hours and was virtually complete after 48 hours. Orientation failed or was partially inhibited in small toads tested under dense cloud cover, at noon, and after sunset. Also, the type of orientation exhibited under the sun was evident at night under the moon, but to a lesser extent under starry skies. These mechanisms are useful in foraging and in dispersal from nursery shores. Adults are oriented at night to the breeding site even without benefit of a chorus for reference. Adults oriented to the Y-axis of the breeding site. A recorded chorus distracted migrating adults pursuing a compass course toward a pond. Non-breeding adults compensated for a displacement made in view of the sun. Celestial orientation is considered a basic orientational mechanism which most likely developed early in anuran history.