Genital mechanics are studied in five species from three genera of neotropical pholcid spiders. The study focuses on the function of a pointed and upward projecting (‘pup’) apophysis on the male pedipalpal femur: it engages an indentation in the genital bulb during copulation. This character is geographically restricted to spiders in Central and North America and the West Indies and is considered a key character of the monophyletic ‘Modisimus group’. This includes the genera Modisimus Simon, 1893, Psilochorus Simon, 1893, Bryantina Brignoli, 1985, Anopsicus Chamberlin & Ivie, 1938, and some species now misplaced in Coryssocnemis Simon, 1893 and Blechroscelis Simon, 1893. Evidence for the polyphyly of the following genera is presented: Psilochorus, Coryssocnemis, and Blechroscelis. Some notes on the reproductive biology of the species studied are briefly presented.

Many life-history traits are allometrically tied to body size, in snakes as well as in other animals. Two problems with previous analyses on this topic for snakes are that: (i) the range of body sizes within species is generally small, so that most analyses have relied on interspecific comparisons; and (ii) available data have been heavily biased towards small, temperate-zone colubroid species. We test the generality of results from previous work with data on a species of giant tropical snake that is phylogenetically and ecologically distinctive, and encompasses such a massive size range that we can examine intraspecific allometries. We use data from >1,000 field-collected reticulated pythons from southern Sumatra to ask two questions: (i) do life-history traits show intraspecific allometries similar to those revealed by interspecific comparisons?; and (ii) are mean values for life-history traits in a giant snake consistent with allometric trends in smaller species? As predicted, strong intraspecific allometry was evident for most of the life-history traits we measured, including reproductive output (e.g. clutch size, frequency of reproduction in females, testis volume relative to body mass) and energy stores (relative size of the abdominal fat bodies). For many traits (e.g. the means and variances of clutch sizes and maternal body sizes, relative offspring size, body size at maturation relative to size at hatching and maximum adult size), these giant pythons were near or beyond the extremes reported for smaller species of snakes, supporting the importance of allometry. None the less, reticulated pythons deviate from many of these previously-documented allometries in significant ways, suggesting that current generalizations about life-history allometry in snakes may be premature.

Sarcocysts morphologically not distinguishable from Sarcocystis gracilis of roe deer (Capreolus capreolus, Cervidae) were found in the skeletal musculature of dwarf zebu and humpless cattle (Bos taurus, Bovidae). We contribute to the identification of this species by means of scanning electron microscopy. Special attention is paid to the species-specific cyst wall structure. Our findings confirm previous descriptions by light and transmission electron microscopy and support the peculiarity and uniqueness of the cyst wall type ‘gracilis’.

Argyrodes flavipes illustrates a novel form of highly social behaviour in spiders. Although A. flavipes lives in groups, forages communally, and has parental care, it is also highly aggressive towards conspecifics. These observations, plus the relatively small group sizes, suggest that sociality in these animals may be more akin to that in social mammalian carnivores than in social insects. Most highly social spiders are thought to have developed sociality via the sub-social route because of their high level of parental care. Although A. flavipes also exhibits high levels of parental care, its phylogenetic background and the fact that it needs to defend its young from conspecifics, suggest that both sub-social and para-social factors may have influenced its social development.

The Namib Desert golden mole (Eremitalpa granti namibensis) is a small (c. 20 g), blind, sand-swimming, chrysochlorid insectivore that inhabits the sand dunes of one of the driest and least productive areas of the world. Its food, largely termites, is sparse and occurs in widely distributed patches, and free water is unavailable. The moles forage by running on the surface and burrowing below the sand. We estimated their daily energy expenditure in the field to be 11.8 kJ d-1 by constructing a ‘distance-energy budget’ based on measurements of tracks in the sand and the energy cost of running (4.2 kJ d-1), burrowing (3.2 kJ d-1), and resting (4.4 kJ d-1). We also measured field metabolic rate (12.5 kJ d-1) and water turnover (2.3 ml d-1) independently with doubly-labelled water. The resting metabolic rate (0.5 ml O2 g-1 h-1 at 35 °C) is about a fifth of that predicted for a normal insectivorous mammal, and the daily field energy expenditure and water turnover are about a half. The low daily energy expenditure stems mainly from the low resting metabolic rate, which is associated with low body temperatures and metabolic depression. Moles save more energy during foraging by running on the surface of the sand, rather than burrowing under it. The gross energy cost of sand-swimming (80 J m-1) is 26 times more expensive than running on the surface (3.0 J m-1), but is less than a tenth of the energy required by mammals that tunnel through compact soil. Nevertheless, it would be energetically impossible for the moles to obtain enough food by foraging only underground at our study site. The mean track length was 1.4 km, but only 16 m of it was below the surface. There is evidence that the track length and fraction underground depend on food abundance which is influenced by rainfall.

Two species of tuco-tucos, Ctenomys talarum and C. australis, overlap geographically in south-eastern Buenos Aires Province, Argentina. C. talarum (100-180 g) occupies habitats with clayey and harder soils, while the larger C. australis (300-600 g) occupies sandy and quite friable soils. This study compares the digging apparatus and digging performance of both species, and also provides additional ecological data to describe the adaptations of both species. When confronted with sandy, friable soils, both tuco-tucos exclusively use their forelimbs (‘scratch digging’ mode) to break the soil. When confronted with harder and clayey soils, C. australis used its forelimbs and, less frequently, its incisors, but no appreciable effectiveness was observed in breaking the soil. On the other hand, C. talarum behaved as a ‘scratch’ and ‘chisel-tooth digger’ species, using both forelimbs and incisors to dig tunnels in extremely hard soils. C. talarum showed relatively larger forelimb extensors than C. australis. Moreover, I hypothesize that the structure of the ulna in C. talarum may increase the effective forces of the digital and carpal flexors, thus accounting for the enhanced digging ability in this species. Outward forces exerted by the distal elements (claws-digits-carpals) when forelimbs impact the soil appear to be a critical factor in loosening soil fragments. In addition, the increased upper incisor procumbency of C. talarum correlated with an effective chisel-tooth digging behaviour. Finally, I briefly examine phylogenetic and biogeographical factors that may account for some C. australis morphological and physiological traits. It is suggested that the digging ability of C. australis could be a by-product of its larger size, a likely adaptation to evade predation.

The ranches of Laikipia District, Kenya, provide a very important refuge and conservation area for wildlife. Leopards (Panthera pardus) are the most numerous large predator and create problems by killing livestock. Both small and young wild ungulates, as well as small domestic stock, provide prey so that the leopards achieve unusually high densities. This study, using radio-tagging techniques, examines the spatial relationships between resident and transient leopards on a 200 km² ranch in the Lolldaiga Hills. About 25 leopards (including estimates of subadults and cubs) live on the ranch. Typically, females occupy exclusive home-ranges of mean extent 14.0 km² although there is some overlap with subadult females. The home-ranges of resident males, with a mean of 32.8 km², do not overlap each other but do overlap female territories. Transient males move through the area. Analysis of home-range and home-range occupancy, was carried out using three methods: minimum convex polygon, grid cell, and harmonic mean. The information provided by these three different methods is compared, and the social status of the leopards is discussed.

A survey of Skomer voles (Clethrionomys glareolus skomerensis) conducted in August of 1994 and 1995 discovered that 51% of live-trapped animals were positive for Cryptosporidium species (Coccidia). Of the positive animals, 85% were shedding C. muris in their faeces, 5% C. parvum and 10% apparently both parasite species. On the U.K. mainland, the prevalence of Cryptosporidium in the bank vole (Clethrionomys glareolus) is a quarter of that on Skomer and the species normally found is C. parvum. Interest in C. parvum stems from the often severe diarrhoeal disease crypt osporidiosis which it can cause in humans and livestock. The parasite occupies the gastro-intestinal tract and is transmitted between hosts by the faecal-oral route. It has been suggested that wild rodents may be an important reservoir of infection by C. parvum for livestock. However, on Skomer island, C. muris, which is rarely found in livestock, is the dominant species infecting voles.

The foot pads of five rodents were studied by means of gross morphology and histology. The secretory portions of the glands are placed caudad to the openings of the ducts in species that mostly walk on the ground. This way the secretions are pressed out during walking by rolling on the foot pads craniad. In climbing species, the secretory portions are placed underneath the openings of the ducts and lead to secretion delivery during climbing by grasping. With their small and flat pads with few glands, digging species have a rather smooth and dry volar aspect to work in a shovel-like way. In contrast, climbing species have large and soft foot pads with a lot of glands. The thickness of the cornified layer is positively correlated with the density of glands and increases strikingly from digging to climbing species. Although scent production is possible for these glands, this points to a function of the secretions in connection with the cornified layer. In climbing species, the secretions of glands can moisten the skin and thereby heighten the friction between volar and climbing surface to prevent the animal from slipping. The density of glands per unit of surface is doubled in the ridged skin of Muscardinus avellanarius in comparison with the coned skin in Micromys minutus. While M. minutus mainly climbs by grasping stalks of reed and can tighten the grip by increasing the grasping force, M. avellanarius often climbs by pressing the volar aspect on to the bark, whereby friction is increased by the moistened skin.

The diet of the brown skua (Catharacta skua lönnbergi) was studied at Mayes Island, Kerguelen archipelago, by collection of prey remains on 11 territories during the complete breeding cycle of the species there. In nine territories, collections were daily or every two days for a quantitative investigation of the diet. The blue petrel (Halobaena caerulea) and thin-billed prion (Pachyptila belcheri) accounted for, respectively, 72.9 and 19% of the remains. Differences in diet and prey capture rate were analysed according to territory size, local abundance of prey inferred from the vegetation cover of territories, colony attendance patterns of prey, and according to the breeding timing and success of skuas. Skuas holding large territories caught more prey, and especially more blue petrels than those with small territories. Diet reflected local abundance of blue petrel and thin-billed prion but the blue petrel was apparently preferred to other available prey. Failure to breed was not significantly related to hunting performance of the skua or to food availability, but sample size was small. Variations over time of prey capture rates reflected the colony attendance patterns of the main prey. Captures of blue petrel and thin-billed prion were most numerous during their respective laying, incubation and hatching periods, decreasing during chick-rearing. Prey capture rates were greatest when brown skuas were hatching, and decreased during chick-rearing to a minimum when young skuas were fledged. Capture rate patterns differed according to laying date of skuas: early breeding skuas caught more prey and were well synchronized with the breeding cycle of the blue petrel and late breeders exhibited more dependence on the thin-billed prion for some periods. Finally, this study has allowed us to assess the impact of the brown skuas upon the burrowing petrels on this locality.

Pipistrellus pipistrellus, Eptesicus serotinus, Nyctalus noctula, N. leisleri, Myotis daubentonii, M. myotis, unidentified small Myotis spp. and Plecotus spp. were recorded during bat detector transects within a central European city of 350,000 inhabitants. Bats were recorded in all seven habitat types under study, the levels of activity for each species and habitat type were significantly different. The relative activity of the whole bat community was highest in old outskirts (low density housing) and at the river, and lowest in the city centre and new housing estates (high density housing). Significant differences were found in the timing of bat activity during the night and the season. Within the first two hours after sunset, relative activity of P. pipistrellus and E. serotinus was highest in the first 0.5 h and decreased thereafter. In N. noctula, it was highest during the second and third 0.5 h and in Myotis spp. it was low in the first 0.5 h and increased till the end of monitoring. Flying bats were recorded from March till October; the lunar cycle had no significant effect on the amount of flight activity. The relative activity of E. serotinus was positively correlated with temperature. No significant correlation was found between the activity of bats and the number of trees and streetlamps per transect. Comparison with the results of an earlier visual census showed that more bats were recorded acoustically than visually except in the city centre. This is attributed to the effect of white streetlamps during the visual census. During the acoustic census, most white lamps were replaced by yellow lamps which biased the impact of lamps on bat traffic. Nevertheless, bat species known to benefit from white streetlamps remained the most common foragers within the city.

This study is an investigation into the influence of activity on otter (Lutra lutra) spraint production and composition, based on feeding trials involving captive, tame otters. Trials were of two types: ‘active’ where animals were encouraged to run, swim and dive for at least 33% of the time during the first six hours after each meal, and ‘inactive’ where activity varied between zero and 18% of this period. Trial types were balanced for number of fish, meal volume and fish size. Activity was found to have a large effect on spraint production and composition. For active trials, median minimum gut transit time was 67 minutes and median number of spraints per trial was 23. Corresponding figures for inactive trials were 170 minutes and 14, respectively. Of ingested salmonid (Salmo spp.) atlas vertebrae, 60% were recovered in spraints after active trials, while only 32% were recovered after inactive ones. Analyses of these effects showed that our previous models for estimating prey size distribution from bones recovered in spraints gave a better fit for inactive than for active trials. As otters in the wild are likely to spraint mostly during periods of activity, especially foraging, further feeding trials were undertaken to refine an earlier model better to mimic the field situation. Trials, involving active otters, were undertaken to: (i) produce in vivo bone to fish length equations for salmonid atlases and eel (Anguilla anguilla) thoracic vertebrae; and (ii) model the size-related differential recovery of these bones. These refined equations are more soundly based to provide estimates of prey size distribution than the earlier ones and their use in future studies of size-selection is recommended. The present study also highlights the potential limitations of extrapolating from the captive situation to the wild.

Rutting calls of male and alarm calls of female red deer (Cervus elaphus), sika deer (C. nippon), and their hybrids were recorded from wild and captive-bred populations. Vocal variations between these species and their hybrids (C. elaphus × C. nippon) were examined using multivariate analysis to determine whether these groups could be successfully discriminated. There were highly significant differences between the vocalizations of each group for both sexes (males: Wilks' Λ = 0.0233, P<0.0001; females: Wilks' Λ = 0.1338, P<0.0001). The greatest differences were between analogous calls of red and sika deer. Vocalizations of hybrids from both captive-bred and feral populations were intermediate between the two parent species. The differences between the groups were most highly influenced by the pitch of calls. The results of this study indicate that the vocalizations of deer, rather than being learned or mimicked from similar species in their proximity, are strongly influenced by the genetic background of their parents.

The vertebral column of Scutisorex somereni (the hero shrew), and its size and morphology, is probably the most modified among the vertebrates (Kingdon, 1974). We examined the scaling of diameter versus length in the long bones and ribs, and spine mass versus body mass of this species, in comparison to 19 other mammalian taxa (including fossorial species). The ribs of Scutisorex are significantly more robust than any genus examined, and the spine of this species, relative to its body mass, is four times more robust than that reported for any other vertebrate. Paradoxically, the long bones of the limbs of Scutisorex demonstrate no difference in robustness from that predicted for an animal of its body mass. There is no satisfactory ecological, behavioural, or functional explanation for this unique spinal morphology.

Mortality factors and hatching success of 422 terecay turtle (Podocnemis unifilis) nests on seven beaches in the Nichare and Tawadu Rivers, Venezuela, were studied following the oviposition phase. Beaches (3.4-28.4 km2), predominantly sandy, and bordered by riparian vegetation, were searched to record nest numbers and their distribution. Elevation and surrounding plant cover were measured for each nest. Most nests were found close to the vegetation's edge (0-11 m), at a significant distance from the water's edge (21-80 m), in more open ground, and along the highest points of the beach (1-2.5 m above the water's edge). Nest density was positively correlated with beach elevation but not with beach dimensions. Most nests were concentrated in less than 10% of beach area, along the upper 20% of the beach. Average clutch size was 20.1±1.7 eggs, but larger clutches were found significantly further away from vegetation. No significant correlation between hatching success and clutch size was found.

A large proportion of nests were subject to animal and human predation but environmental factors (especially flooding) affected some. The major cause of egg loss was human predation. Most clutches collected by humans were found away from vegetation, on the upper 10-20% of beaches, in exposed unvegetated sites. Animals preyed upon those nests along the vegetation's margin (1-2 m) in the upper 0-9% of beaches, in sites of high plant cover (75-100%). Nests reaching the incubation phase were mainly located in the open areas, which are more prone to human predation. About three-quarters of nests showed high hatching rates (91-100%). However, hatchability was highest furthest away from the vegetation. Our results indicate that humans are collecting eggs mostly from sites in which nests have the larger clutches and the higher potential hatching success. Because of this relationship between nest viability and location, sustainable yield programmes must consider where harvesting can take place and must avoid the application of standard harvests per nest.

In lizards, the basic lepidosaurian bauplan of the skull is modified by the reduction of one or more skull elements such as the lower temporal bar (e.g. iguanids), the upper temporal bar (e.g. varanids) and the postorbital bar (e.g. geckos). Skull modifications in Plocederma stellio, Uromastix acanthinurus, Corucia zebrata and Tiliqua scincoides are restricted to the reduction of the lower temporal arcade (the plesiomorph condition for lizards; i.e. possessing a ‘basic’ skull). In spite of the potential mobility (streptostyly) of the quadrate, none of these species shows streptostylic movements during the static power phase of biting. It is assumed that the temporal ligaments fulfil the role of the lower temporal arcade in stabilizing the quadrate. This function is supported by the results of mathematical simulations, which demonstrate that static biting loads the ligament in tension. Apparently, these basic lizard skulls show a shift of the attachment site of the temporal ligament from the quadrate to the lower jaw. This does not affect its quadrate-stabilizing function. However, analyses of forces occurring in the quadratomandibular joint suggest that skull configurations with a jugomandibular ligament confine the possible orientations of the joint forces to a narrow range, more aligned with the quadrate. In this way, optimization of the joint morphology to resist loads imposed by biting might more easily be reached. This is assumed to be important for lizards with a robust skull built for forceful biting.

The spine of Scutisorex somereni, the hero shrew, is probably the most highly modified among the vertebrates (Kingdon, 1974), yet no description of the accompanying spinal musculature has been published. This paper describes the anatomy and proposed functions of the major epaxial and hypaxial muscle groups of Scutisorex. The unusual vertebral morphology of this species is accompanied by major modifications in some of the spinal muscle groups. The transverse spinalis muscles are the most modified, and this is probably related to the presence of bony interdigitating tubercles on the vertebrae. The longissimus muscles possess long tendons that share attachment with the iliocostalis muscles. The iliopsoas muscles and their sites of attachment are greatly enlarged in comparison to those of Blarina and Rattus. Much of the spinal musculature reflects the highly modified state of the Scutisorex vertebrae. The unique behavioural function of the Scutisorex spinal modification, if any exists, is not known

Using the African diederik cuckoo Chrysococcyx caprius and four sympatric passerine foster species in the subfamily Ploceinae, we show that nestling cuckoos are infested by feather lice and mites derived from the ectoparasite fauna typical of the foster species. Adult cuckoos had five species of lice and mites normally found on ploceines, which demonstrates that these ectoparasites are able to survive on foreign hosts. This is the first record of persistence of passerine ectoparasites on a cuckoo. Adult diederik cuckoos also harboured four species of mites and lice specific to cuckoos; since these were not detected on nestlings, cuckoo-specific lice and mites apparently transfer to cuckoos after they leave the nest. Contrary to prediction, ectoparasites with a life cycle involving a permanent association with their host (feather mites and lice) were more likely to transfer to cuckoo nestlings than ectoparasites which spend part of their life cycle away from their host (haematophagous mites and phoretic skin mites). New host records are established for the lice genera Brueelia, Cuculoecus, Machaerilaemus, Myrsidea, Philopterus as well as for the mite species Microlichus americanus, Ornithonyssus bursa, Ornithocheyla megaphallos, Pellonyssus reedi, Pteronyssoides passeris, Pternonyssus glossifer, Trouessartia baupi, T. carpi, Xolalges plocei, X. scaurus and the mite genus Passeroptes.

The phylogenetic relationships of eight genera within the Calappidae H. Milne Edwards, 1837 (Crustacea: Brachyura) were examined based on a cladistic analysis of 55 adult morphological characters. A single tree was produced (CI=0.833, RCI=0.717). The data revealed two major lineages within the Calappidae: the ‘calappine’ clade, consisting of Calappa, Cryptosoma, Cycloes, Paracyclois and Cyclozodion, and the ‘mursiine’ clade, consisting of Acanthocarpus, Mursia and Platymera. Analyses of the fossil record and biogeographic patterns point to vicariance events associated with Gondwanan fragmentation. Optimization of depth distributions on the cladogram suggests that the family had a deep-water origin with only a single lineage moving into shallow waters.