Onychophora lead a cryptic lifestyle as predators in decaying logs and leaf litter. Hence, very little is known about their behaviour. They are generally assumed to possess only a limited behavioural repertoire, even though their surprisingly evolved brain suggests otherwise. Our studies on the Australian species Euperipatoides rowelli show for the first time that onychophorans are indeed capable of complex behaviour. Euperipatoides rowelli individuals form aggregations of up to 15 females, males and young. These aggregations are not random assemblages, but close social groups organized in a hierarchy based on female dominance. Food is hunted collectively, but the dominant female of a group feeds alone, before other females, males and young. Hierarchy within a group is established by aggressive-dominant and passive-subordinate behaviours, the latter leading to tolerance of body contact and aggregation. Euperipatoides rowelli from foreign groups, i.e. from different logs, are met with intense aggression, and individuals rarely aggregate. The reasons for this aggression are not clear, but we suggest that its origins lie in kin recognition. The evolution of social behaviour within the Onychophora is discussed with respect to their ecology, population genetics and phylogeny.

In the final stages of an elaborate courtship, many slugs and snails shoot calcareous ‘love’ darts into each other. While darts improve the reproductive success of the shooter, by promoting sperm survival in the recipient, it is unclear why some species have darts and others do not. In fact, dart use has barely been studied, except in the garden snail Cantareus aspersus (Helix aspersa). An evolutionary approach was therefore taken to attempt to understand the origin and use of darts, by investigating mating behaviour in a wide range of species. The prediction was that, because darts could have arisen out of an escalating cycle of sperm digestion and investment in sperm, then darts should be found in taxa that enforce simultaneous reciprocity during mating. Likewise, they should not be found in taxa that mate unilaterally, because the co-evolutionary cycle is absent or reduced. Mating behaviour in 60 genera (28 families) of land snails and slugs was recorded, and compared against dart use across the whole of a stylommatophoran phylogeny. ‘Face-to-face’ simultaneous reciprocal-mating behaviour is restricted to three monophyletic groups of snails and slugs, and dart-bearing species are a subset within the same clades, which suggests a link, though not necessarily a causal one. As yet, we are unable to quantify the extent to which darts or mating behaviour, as well as several other correlated characters, are determined by common ancestry or regimes of natural or sexual selection, because the current phylogeny lacks resolution. However, the results emphasize that to understand the use of darts, then data are required from a wide range of species. The realization that several characters are correlated may stimulate further research, and could eventually lead to some testable models for dart and mating behaviour evolution.

The territorial behaviour and the social–spatial activity of Ochotona hyperborea during the hay-storage season are described and a comparative analysis of Asian and American rock-dwelling species is presented. Seven pairs of O. hyperborea held territories of c. 900 m2, used the same shelter, spent most of their time in the same core area and stored food collectively. Males and females differed in mobility, and behaviour related to defence of territory. The intercontinental comparison of the behaviour and ecology of pikas, based on these data and on published information, revealed that despite different social organization, their mating systems, life-history parameters and population characteristics are very similar.

Catastrophic declines of amphibian populations have been reported from upland areas around the world, yet within regions not all species have been affected. Herein, we examine the relationships between conservation status and ecological traits for over 60 amphibian species from upland areas of eastern Australia. Among the 24 phylogenetic groups examined, eight groups contained only declining species, eight groups contained both declining and non-declining species and eight groups had no declining species, suggesting species declines are influenced by their evolutionary history. Declines have been reported for only one species (Philoria frosti) of 20 species (i.e. from genera Assa, Cophixalus, Austrochaperina and remaining Philoria/Kyaranus) with direct development in the terrestrial environment. Of the remaining 40 species that include an aquatic stage in the life history, species-specific traits associated with declines suggest species with stream-dwelling tadpoles are more likely to be declining than species that breed in ephemeral and isolated ponds. However, low ovarian clutch size is the most important ecological trait significantly associated with the tendency for a species to be declining (independent of phylogeny). Species with restricted geographic ranges are also more likely to be declining than widespread species (independent of phylogeny). While ovarian clutch size and geographic range are correlated they are both good predictors for the likelihood of decline for upland species independent of their phylogenetic history. We propose that low ovarian clutch size is an index of low fecundity, and indicates a reduction in population resilience, making those species more susceptible to population declines and extinction than highly fecund species. This provides the first ecological explanation for why some species are declining while other sympatric species are not. Geographic range provides an easily applied tool that can be used to predict the likelihood of species decline in other regions. These results support the hypothesis that a causal factor may be affecting all species of frogs, yet only those species with naturally low population resilience are susceptible to declines.

For 40 years there have been problems in diagnosing sexual patterns in the serranid genus Paralabrax. Difficulties stem from a combination of factors including terminology, histological and morphological characteristics, and the complex inter-relationships in the Serranidae between gonad morphology, phylogenetic position and gonad function. A detailed study of four species of Paralabrax: P. maculatofasciatus, P. nebulifer, P. auroguttatus and P. clathratus, clarifies the problems and improves the diagnosis of sexual pattern in the Serranidae, and for similar families that do not have distinct morphologies for primary- and secondarily-derived males. An hypothesis was developed to account for the multiple appearance of gonochorism in the Serranidae, better known for its widespread hermaphroditism.

An objective multivariate technique is described for identification of individual tigers Panthera tigris from their pugmarks. Tracings and photographs of hind pugmarks were obtained from 23 pugmark-sets of 19 individually known tigers (17 wild and two captive tigers). These 23 pugmark-sets were then divided into two groups, one of 15 pugmark-sets for model building and another of eight pugmark-sets for model testing and validation. A total of 93 measurements were taken from each pugmark along with three gait measurements. We used CV ratio, F-ratio and removed highly correlated variables to finally select 11 variables from these 93 variables. These 11 variables did not differ between left and right pugmarks. Stepwise discriminant function analysis (DFA) based on these 11 variables correctly classified pugmark-sets to individual tigers. A realistic population estimation exercise was simulated using the validation dataset. The algorithms developed here correctly allocated each pugmark-set to the correct individual tiger. The effect of extraneous factors, i.e. soil depth and multiple tracers, was also tested and pugmark tracings compared with pugmark photographs. We recommend collecting pugmarks from soil depths ranging between 0.5 and 1.0 cm, and advocate the use of pugmark photographs rather than pugmark tracings to eliminate the chance of obtaining substandard data from untrained tracers. Our study suggests that tigers can be individually identified from their pugmarks with a high level of accuracy and pugmark-sets could be used for population estimation of tigers within a statistically designed mark–recapture framework.

The aim of this study was to determine the extent to which mongooses Herpestes javanicus in the Caribbean National Forest use areas of high human use, and to compare space use patterns in these areas to those in areas of low human use. It was expected that the abundance of anthropogenic food in areas of high human use would lead to (1) higher population densities; (2) smaller home ranges; (3) more extensive range overlap and reduced territorial behaviour, than areas of low use. During the dry season, 14 mongooses were radio-collared and tracked in each of two areas: an area of high human use and an area of low human use. Six of these mongooses, one in an area of low human use and five in an area of high human use, were also tracked during the wet season. In both seasons, mongooses in the area of high human use used picnic areas more than expected based on availability. In the dry season, mongooses in the area of high human use had smaller home ranges than those in the area of low human use. Ranges overlapped extensively in both areas, and slightly more so in the area of low human use. However, individuals avoided each other spatially within the shared area of their ranges, and core home ranges overlapped little. In the wet (breeding) season, home-range size and overlap increased more for males than for females. Such differences in behaviour and population dynamics in these two areas have implications for rabies transmission rates and management throughout the forest.

The skulls and mandibles of 50 (28 male, 22 female) captive muntjac Muntiacus reevesi of exactly known age and four (two male, two female) of approximately known age were examined for their molar wear patterns. A procedure for scoring was based on earlier published work (Brown & Chapman, 1990, 1991) for fallow Dama dama and red deer Cervus elaphus, respectively. Specimens were also available from 17 male and 13 female wild muntjac whose approximate ages were known. The data show a curvilinear relationship between age and toothwear score, with increasing variability as the score increases. The predicted age and upper and lower limits of 95% prediction intervals are given for captive and wild muntjac deer. The range between upper and lower limits, though greater than was found for fallow and red deer, may still be a useful guide for assessing animals of unknown age.

A biomechanical approach is used to model the mandibles of extant carnivoran predators (felids, canids, and hyaenids) as beams to gain insight into feeding behaviours. Because bite force applied at any given point along the mandible should be proportional to external dimensions at an analogous location (interdental gaps) on the mandible, patterns of variation in these dimensions will reflect the adaptation of the jaw to specific loads. The mandibular force profiles of extant carnivorans closely reflect particular feeding behaviours. Solitary hunters relying on a powerful canine bite to subdue their prey have a strong mandibular symphysis, while pack hunters delivering shallow bites have a relatively weaker one. Symphyseal shape also gives insight into the feeding behaviour of a predator: (1) a deeper-than-long symphysis indicates that stresses induced by the canine bite (or while cracking bones with the anterior dentition) are more important than those induced by struggling prey; (2) an equidimensional symphysis indicates that the symphyseal region is optimally designed to resist torsional stresses induced during prey capture and/or bone cracking; (3) a longer-than-deep symphysis indicates that stresses related to prey capture are predominant over those induced by the canine bite or while cracking bone. Mandibular force profiles of juvenile carnivorans also reflect documented ontogenetic changes in feeding behaviour. Because variation in mandibular cross-sectional properties are interpretable in terms of documented behaviours among extant predators, mandibular force profiles are developed to gain insight into the feeding behaviour of two extinct predators, Panthera atrox and Canis dirus. Results indicate that the feeding behaviour of P. atrox differed slightly from that of modern lions, as the powerful paws restrained prey more efficiently, while C. dirus hunted in a similar fashion to the gray wolf, although it may not have been an efficient bone cracker. Both extinct predators are inferred to have had a more powerful bite than their extant relatives.

Sperm competition occurs when the gametes of two, or more, males compete for opportunities to fertilize a given set of ova. This study examined whether mammalian sperm morphology could be affected by sexual selection. Comparisons were made of linear and volumetric measurements of the sperm head, midpiece and flagellum for 123 species representing 71 genera of mammals having either single partner mating systems or multiple partner mating systems. Sperm midpiece volume was found to be significantly larger in those species were females mate with more than one male during a single peri-ovulatory period. A positive correlation was also found between relative testes sizes and sperm midpiece volumes, while no relationship was found with any other sperm measure. These results indicate that, within mammals, the evolution of sperm midpiece volume has been affected by selection pressures resulting from sperm competition. The significance of these findings may relate to the density of mitochondria within the sperm midpiece. The mitochondria provide the energy required for sperm motility, in the absence of glycolytic support. A higher mitochondrial loading may therefore be associated with enhanced sperm motility.

Terrestrial locomotion requires that animals maintain postural stability against the flexing force of gravity. To counteract volume/area relationships that limit muscle force and may compromise stability, larger animals increase the effective mechanical advantage of their extensor musculature by walking on more extended limbs and showing allometric increases in extensor muscle lever arm lengths. Assuming these size-related principles are uniform, similar adaptations should characterize ontogenetic increases in size. Previous research on non-primate mammals has shown, however, that extensor muscle mechanical advantage is greater early in ontogeny and decreases with negative allometry during growth. This study extended this work by investigating patterns of relative elbow lever arm growth in two capuchin monkeys, Cebus albifrons and Cebus apella. Unlike previously studied mammals, growing capuchin monkeys face unique anatomical constraints, including relatively long limb bones and positively allometric limb growth. These constraints could augment the flexing torque of gravity at the limb joints and require compensatory increases in extensor muscle mechanical advantage as size increases through growth. Forearm length and the length of elbow extensor and flexor muscle lever arms were measured in longitudinal radiographic series of growing capuchin monkeys. In contrast to other mammals, all lengths scaled to body mass with positive allometry. Anatomical mechanical advantage (lever arm length/forelimb length) scaled with negative allometry, however, matching the non-primate mammalian trend. Greater muscle mechanical advantage during early locomotion may help young mammals overcome relatively weak extensor muscles and other growth-related limits on locomotor performance. Additional data on ontogenetic changes in gait dynamics and musculoskeletal growth are required to validate this hypothesis.

Ontogeny and sexual dimorphism have been important topics of investigation among researchers interested in the life history and ecology of non-human primates. It has been suggested that sex differences in the duration of growth are primarily, but not entirely, responsible for the sexual dimorphism observed in primate species with multimale–multifemale social structure, such as that seen in macaque monkeys (subfamily Cercopithecinae). Sexual dimorphism and growth was investigated in a wild population of booted macaques Macaca ochreata from Sulawesi, Indonesia. The results of our investigation suggest that the observed dimorphism in this population is primarily a product of greatly increased growth rates in dentally mature young adult males, in addition to prolonged male growth. This pattern of male growth may be an adaptive response to reduce the risk of adult male aggression before obligatory male emigration, and to facilitate competition for females soon after immigration into a new social group.

This paper gives a detailed analysis of Greek language elements in sponge terminology and nomenclature, thus contributing to its comprehension by the scientists working on sponge biology and enlightening the extensive contribution of the Greek language to zoological terminology. The contemporary terminology of sponge morphology and the taxa names of the three living classes of the phylum Porifera, down to the genus level, were recorded and examined for their possible Greek origin. The analysis of the recorded material showed that 67% of the morphological terms and 78% of the taxa names were formed from Greek elements. Different patterns of term and name formation were revealed. Detailed etymological analysis is presented for all morphological terms and suprageneric taxa names built of Greek elements. The Greek words used for the formation of terms and names are listed and their English translation is given. More than 70% of the Greek words found were used only once to form terms or taxa names. The contribution of the Greek element in sponge nomenclature in all decades from 1759 up to the present was >65%, with a slightly decreasing trend during the last two decades.

Observational and telemetry data were used in a geographic information system database to document the ontogenetic development of sexually dimorphic patterns of space use among free-living spotted hyenas Crocuta crocuta in Kenya. No measures of space use were sexually dimorphic among den-dwelling cubs, nor were sex differences apparent among hyenas that had ceased using dens for shelter until these animals were c. 30 months of age. Significant sex differences emerged late in the third year of life, and persisted throughout the remainder of the life span; males were found farther from the geographic centre of the natal territory than were females, and the mean size of individual 95% utility distributions was larger for males than females. Most dispersal events by radio-collared males were preceded by a series of exploratory excursions outside the natal territory. All collared males dispersed, but no collared females did so. Most dispersing males moved only one or two home ranges away at dispersal, roughly 8–10 km distant from the natal territory, before settling in a new social group.

Diet was manipulated in juveniles of the snake Boa constrictor (Serpentes: Boidae) to test the hypothesis of whether prey size induces phenotypic plasticity of the head skeleton. Additionally, the onset of sexual size dimorphisms (SSDs) was determined under a feeding schedule where total prey mass consumed by snakes was held constant. Twenty-three neonatal B. constrictor from a single-sired litter were placed into two treatment groups but maintained under identical environmental conditions. Group 1 (small-food treatment) was fed weanling mice throughout the entire study; group 2 (large-food treatment) was fed weanling mice, followed by rats of increasing size as the size of the snakes increased. At the termination of the study, group 1 consumed more meals but both groups consumed an equivalent mass of rodents. The snakes were measured twice during the study (5 weeks and 58 weeks). All measurements were obtained while the snakes were under general anaesthesia. Linear measurements of the head skeleton (premaxilla–basioccipital (rostrum–occipital) length, ROL; mandible length, ML) were derived from radiographs. The remaining measurements were snout–vent length (SVL), body length (BL), tail length (TL), and body mass (BM). Treatment effects between groups were equivalent, with the exception of BM and TL (group 1>group 2), and interactions between main effects were not statistically significant. Between-group differences in ROL and ML were not significant; thus, prey size did not exert an influence on growth of the head skeleton. In contrast, significant sex effects on SVL and BL (females>males) and TL (males>females) were detected, and sex effects on BM (females>males) approached significance. Because SSDs emerged during early ontogeny under conditions where prey mass consumed was held constant, a genetic role is implicated.

Predation between invading and native species can produce patterns of exclusion and coexistence. Dikerogammarus villosus, a Ponto-Caspian amphipod species, has invaded many central European freshwaters in the past decade, replacing native Gammarus amphipod species. For instance, the arrival of D. villosus in Holland has been accompanied by the decline of Gammarus duebeni and G. tigrinus populations within invaded systems. This study examined what may happen when D. villosus eventually encounters native Dutch populations of Gammarus pulex, and how factors such as microhabitat and food resource availability could contribute to a future species replacement or coexistence. A laboratory simulation of a lake/pooled area of river indicated that G. pulex and D. villosus differed in distribution within the same habitat, and showed that although the distribution of the native differed in the presence of the invader, the presence of the native had no effect on the distribution of the invader. Gammarus pulex suffered severe intraguild predation (IGP) from D. villosus in mixed species treatments with no reciprocal predation of D. villosus by G. pulex. This IGP occurred regardless of whether no alternative food resource was available (91% of the G. pulex population eliminated after 7 days), or alternative foods/prey were available to excess, such as leaf material (85%), chironomids (77%) or fish food flakes (74%). We conclude that although differential microdistribution of the two species could promote coexistence, the presence of alternative foods/prey resources, merely slow the rate of IGP and replacement of the native by the invader. Our study joins one of an increasing number emphasizing the potential damaging impacts of D. villosus on native communities.

The distinctions between a predator's diet, its prey-choice behaviour and its preferences are illustrated in a study of Aelurillus muganicus, a salticid spider from the Apsheron Peninsula in Azerbaijan. Laboratory experiments showed that A. muganicus has an innate predisposition to choose ants as prey. The natural diet of this species was determined by sampling individuals seen feeding in the field (n = 64). Ten arthropod orders were represented. Seven were from the class Insecta (Coleoptera, Collembola, Diptera, Heteroptera, Homoptera, Hymenoptera, Lepidoptera) and three from the class Arachnida (Acari, Araneae, Pseudoscorpiones). Collectively, four orders accounted for >70% of the prey records: Hymenoptera (20%), Lepidoptera (19%), Acari (19%) and Homoptera (14%). No other order accounted for >10% of the prey records. Of the 45 insects among the prey, 13 (29%) were Hymenoptera, with ants (family Formicidae) alone accounting for 24% of the prey records. Although ants were the preferred prey of A. muganicus, as revealed by laboratory testing, and also the most common single category of prey from the field prey records, records of A. muganicus feeding on prey other than ants were actually more common than records of it feeding on ants, suggesting that, besides prey choice, other factors have a strong influence on the diet of this species.

Locomotion of the box jellyfish Chiropsalmus sp. (cf quadrigatus)1 (Haeckel) and Chironex fleckeri (Southcott) was analysed using digital video. Specimens of Chiropsalmus sp. and C. fleckeri were collected in 2001 and 2002, respectively, from coastal waters of Northern Queensland, Australia. Chiropsalmus sp. animals were videoed swimming in an aquarium, and C. fleckeri in a large outdoor tank. Locomotor sequences of nine Chiropsalmus sp. and seven C. fleckeri individuals were analysed using video techniques. A subset of animals had fluorescent dye injected into the sub-umbrellar cavity, to allow observation of water movements during ejection from the bell. Both species used an intermittent style of jet propulsion similar to that documented for some other species of cubozoan medusae. Computer analysis allowed examination of positions of bell parts over time intervals (0.04 s) by comparing coordinates of nodes marked on various bell parts using imaging software. Examination of node coordinates allowed a detailed qualitative description of gait, in addition to quantitative statistical analyses. General linear modelling showed that interspecific differences in locomotion were explicable in terms of body size. Larger animals of both species tended to swim faster, and with a lower pulse frequency, than smaller individuals. Smaller animals also tended to swim faster relative to their bell diameter.

Acanthocephala are parasites with complex life cycles involving arthropod intermediate hosts and vertebrate final hosts. They use predation as a means of transmission, and some species have developed the ability to modify behaviour of their intermediate hosts to enhance the probability of ingestion by the definitive host. Knowledge of how a single parasite species is adapted to modify the behaviour of different intermediate host species is important for the understanding of parasitic transmission in host communities. In Burgundy, the freshwater amphipod crustaceans Gammarus pulex (native species) and Gammarus roeseli (eastern European invader) are both intermediate hosts for the acanthocephalan Polymorphus minutus. The influence of this bird parasite on the geotaxis of G. roeseli was evaluated and it was found that when infected, individuals of this host species have a negative geotaxis compared to uninfected individuals. There were two components to the behavioural changes: swimming to the top of the water column, and clinging to surface material. These changes were comparable to those observed in the local host species G. pulex, but lower in magnitude. This result contrasts with a previous study on the influence of the fish parasite Pomphorhynchus laevis, which is able to alter the native species' behaviour, but not that of the invasive host. Parasite adaptations to local vs invasive intermediate host species are discussed in terms of their dispersal range (i.e. dispersal of their definitive hosts): the wider the dispersal, the greater should be the spectrum of intermediate hosts.

The diet and pattern of food resource use by the pygmy skunk Spilogale pygmaea, an endemic and threatened species of western Mexico, was evaluated in the tropical dry forest of Chamela, Jalisco. Analysis of scats (n = 104) and stomach contents (n = 5) obtained during 1997, 1998 and 2000 showed that pygmy skunks fed mainly on invertebrates. Insect larvae constituted the most represented food item in samples. During 2000, food resource use was quantified by comparing occurrence of available prey with occurrence of items found in scats. Even though pygmy skunks seem to be opportunistic foragers, some invertebrates were positively selected, such as insect larvae and Myriapoda, thus suggesting that pygmy skunks may target prey of high nutritional value. The diet varied considerably between consecutive dry and rainy seasons of the studied years, with little overlap in food items. Pygmy skunks may adjust food resource use in response to temporal variations in prey abundance, by incorporating other food items in their diet during the dry season, when food is scarce. Dietary switching between seasons indicates that pygmy skunks may exhibit strategies similar to those of other tropical carnivores to deal with a highly seasonal environment.