The taxonomy and/or natural history of 33 species of scincid lizards from Madagascar are reviewed. Most of the material, consisting of 187 specimens now housed in the Museo Regionale di Scienze Naturali, Turin, Italy, has been collected recently, but some dates to the 19th century. Nine new species are described in three genera: Amphiglossus mandady, A. nanus, A. spilostichus, A. stylu, A. tanysoma, Paracontias manify, P. hafa, P. tsararano and Pseudoacontias menamainty, increasing the known skink fauna of Madagascar (62 species) by 14.5%. All the new species come from the closed forests of north-eastern Madagascar. Additionally, Amphiglossus praeornatus is resurrected from the synonymy of A. frontoparietalis, and Androngo alluaudi, A. crenni and A. elongatus are transferred to the genus Amphiglossus. There is also a key to the species of Paracontias and a new interspecifically variable character for Mabuya. Information on morphological variation, basic reproductive biology, habits and habitats is provided, as available, for all species. Perhaps most interestingly, Amphiglossus nanus n. sp. represents the eighth skink lineage in which an oviduct has been lost and Amphiglossus melanopleura decreases the number of longitudinal scale rows at mid-body and the number of subdigital lamellae with altitude.

During terrestrial locomotion, frogs use two distinct gaits: out-of-phase leg movements associated with slow crawling behaviour and in-phase leg movements during fast jumps. In Rana esculenta, crawling occurs during feeding, while jumping is used as an escape strategy. We examined whether a similar velocity-dependent gait shift appears in swimming R. esculenta. Typically, swimming frogs propel themselves by kicking both hind limbs simultaneously. Observations of out-of-phase leg movements in swimming frogs have been reported, but were usually assumed to be associated only with directional changes. We demonstrate that alternating-leg swimming is used quite frequently and that it results in a significantly lower velocity to the one obtained by using in-phase leg movements. This difference is likely to be associated with energetic costs. Mathematical estimates of positive mechanical work required to move the centre of mass revealed that out-of-phase swimming is energetically less expensive than the in-phase gait at a comparable speed, but may not be efficient at high speeds. Possible explanations for this phenomenon are higher inertial energy losses for in-phase swimming, but at high speeds jet propulsion and an interaction effect may gain importance.

Foraging behaviour of the black-necked stork (BNS) Ephippiorhynchus asiaticus was studied in 1996 and 1997 in Dudwa National Park (DNP), Uttar Pradesh, India. The storks were observed using tactile and visual techniques to catch fish. Of the 929 fish seen caught in 2 years, 894 (96%) were caught by a tactile mode of feeding and the remaining 35 (4%) by a visual mode of feeding. The rate of foraging attempts by BNS fluctuates with that of season in DNP and coincides with prey abundance. Immediately after the monsoon when the water level was high, BNS had to search for prey more often, as the prey became widespread. Whereas in summer when the water level decreased, the concentration of the fish was higher, which helps BNS to catch fish in quick succession. Prey behaviour and the condition of the wetland determined the selection of the tactile foraging technique among the BNS in DNP. The black-necked storks were more successful in the early hours of the day (06:00–10:00) and they were generally more successful or preferred to feed on medium-sized fish (i.e. 5–10 cm) in DNP. Prey profitability was highest for larger size fish and decreased as the prey size decreased. Principal component analysis showed that prey size, handling time of each prey, the month and water depth determined foraging success in 1996 and 1997.

The age of crabeater seals Lobodon carcinophagus was first estimated from the teeth by counting layers in the dentine in transverse sections of the canine teeth. Reliable estimation of age from canine teeth in animals older than c. 10 years is not possible because of root closure at a relatively early age. The present investigation compared various methods of estimating age by examination of tooth sections from a large sample of crabeater seals from Marguerite Bay, Antarctic Peninsula. The most reliable estimations were shown to be obtained by counting layers in the cementum of the third postcanine tooth. Ages of 1233 animals (58% female, 42% male) ranged from 0.5 to 39 years. It is suggested that time- and age-specific historical material is potentially relevant for contemporary growth and life-history studies as well as for trophic relations or concentrations of pollutants in animal tissues.

The aim of this study was to investigate age-related growth in the Sumatran elephant Elephas maximus sumatranus and to use the derived relationship to determine the age structure of the wild elephant population in Way Kambas National Park (WKNP), Sumatra. Shoulder height, forefoot circumference and diameter of dung bolus were found to be related to age of captive Sumatran elephants using the Von Bertalanffy growth function. All length measurements were highly correlated with age in the Sumatran elephant and provide growth models for determining the age structure of wild populations. Female captive elephants reached their growth plateau earlier than male elephants who continued growing throughout the ages observed. There was no clear evidence of a secondary growth spurt in male elephants. The growth model relating dung diameter to age was used to predict the age structure of the wild elephant population in WKNP from dung measured along random line transects. The wild elephant population in WKNP is young and dominated by sub-adults (between 5 and 15 years of age). There are marked differences between the age structure of the population as revealed in the current survey and that reported from previous studies, suggesting that changes have occurred within the population in the intervening period. The use of dung diameter to predict age offers a robust field technique for use in situations where direct observations are limited, and the use of other age estimation methods is impractical. It is easily coupled with dung counts for estimating the size, age structure and biomass of elephant populations, and has considerable potential for investigating the effects of poaching on age structure and identifying where priority action should be directed in human–elephant conflict situations.

The effects of mountain lion Puma concolor predation on guanaco Lama guanicoe mortality was investigated during the historically severe winter of 1995 in Torres del Paine National Park, Chile. The 45 guanaco carcasses located represented 3% of the entire guanaco population of which 74% were mountain lion kills, 13% died from malnutrition, 2% died from fence entanglement and 11% died from unknown causes. Depleted bone marrow fat was observed in 20% of all carcasses. The number of guanaco deaths differed among sex and age classes, particularly in juveniles (< 1 year of age), which died more often than expected (P < 0.001). Fresh guanaco carcasses (n = 19) killed by mountain lions were located in tree and shrub habitats 79% of the time and were significantly greater than expected values based on the relative availability of these habitats (P < 0.001). Observations of the spatial distribution of mountain lion kills and guanaco mixed-sex groups were similar (P = 0.10), suggesting that mountain lions responded to winter migratory movements made by guanacos. Overall, adult guanacos experienced surprisingly lower levels of mortality (adult male = 1%, adult female = 2%) than expected, despite the severe winter conditions, while juveniles experienced higher levels of mortality (13%) than expected. In comparison to other years (1991–96), the severe winter of 1995 (i.e. this investigation) had the greatest total mortality for juveniles, although the proportion of deaths caused by mountain lion predation for juveniles was greatest during other winters.

This work examines whether stepwise discriminant function analysis of a suite of craniodental variables enables feeding behaviour and habitat preferences to be identified in fossil ungulates. There are several morphological features of the ungulate skull, mandible and dentition that are well correlated with dietary adaptations, and thus can be used for estimating the feeding ecology of extinct taxa. However, most studies have followed an univariate approach for characterizing the relationship between diet and craniodental structure in extant ungulates (but see Pérez-Barberia & Gordon, 2001), even though such a relationship has been revealed to be complex because of functional, phylogenetic and biomechanical constraints. In this paper a multivariate perspective is followed, developing quadratic discriminant functions for pairwise comparisons of dietary/habitat groups in modern species. Given that the stepwise method for selecting the morphological variables to be included in the algorithms was used, alternative discriminant functions are provided. Results obtained show that these algorithms reclassify correctly the species according to their feeding and habitat ecology, and thus may be useful for obtaining reliable palaeoautecological inferences (i.e. those related to the life style of extinct species, such as feeding ecology and habitat preferences) when applied to extinct ungulate taxa.

The resource dispersion hypothesis (RDH) proposes that in a spatially and temporally heterogeneous environment the territory size of social carnivores increases as the dispersion of limited resources is more widely spaced, whereas group size is limited, independently, by the richness or abundance of those resources or key habitats. To assess if white-nosed coatis Nasua narica behave in accordance with the RDH, the relationship between home-range size and spatio-temporal availability of resources in Mexican tropical dry forests with marked seasonal rainfall was examined. Specifically, home-range sizes were compared at two study sites that were broadly similar but contrasting in resource abundance and dispersion. Home-range estimates for seven white-nosed coati bands varied between 45 and 362 ha. Home-range size did not correlate with food resource abundance and was better explained by the dispersion of water sources during the dry season. Average home-range size was three times greater at the site where water sources were more widely separated during the dry season. These results are in accordance with the predictions of the RDH, and provide an example where the critical resource determining range size and configuration is water.

Life-history details of the live-bearing Peripatoides novaezealandiae (Hutton) were obtained by measuring and dissecting field collected animals. As in other studies, the sexes were found to have different demographics. Sex-specific weight frequency distributions and regression of weight vs length suggest sex differences in patterns of growth and/or mortality. Mature males were smaller than mature females; females apparently undergo a further period of growth between maturity and the onset of embryo production. The sex ratio of the whole sample was female biased; the sex ratio in the smallest size class was 1:1, and then oscillated from female- to male-, and then back to female-biased as size increased. Embryos were unable to be sexed. The sex ratios in individuals of mature (i.e. mating) size, and of reproductive size, were both 1:1. Females, especially but not exclusively before the onset of embryo production, had widely varying numbers of sperm in their haemolymph, indicating dermal-haemocoelic sperm transfer. These data also suggest that females are able to mate throughout life. Numbers of sperm in spermathecae of females were negatively correlated with body size. Fecundity increased with size in both sexes, somewhat more so in females. Embryo weight was correlated with maternal weight only at the beginning of the embryo's development. Rotting logs containing small populations contained a disproportionate number of large females.

Patterns of reproductive phenology and temporal variation in species composition and age structure were investigated for a sample of terrestrial leaf litter frogs from a lowland tropical rainforest in north-eastern Costa Rica. Recruitment of most species showed a seasonal pattern in which the growth of juveniles occurred during the dry season. The phenology of the assemblage was also seasonal, with a peak in abundance during the dry season. Variation in abundance was driven by seasonal patterns of juvenile recruitment in one species, Eleutherodactylus brandsfordii. We suggest that the timing of reproduction and patterns of frog phenology may be tied to the availability of arthropod prey items. A comparison of our data with data collected at other rainforest sites in Central America and the Amazon basin of South America indicates that patterns of recruitment and abundance, while correlated with arthropod abundance on both continents, show divergent seasonal patterns. This and other studies indicate that peaks in abundance and recruitment of juvenile frogs are concentrated in the dry season in Central America, whereas in South American rainforests, the wet season is the period of highest abundance and juvenile recruitment. We suggest that the length and severity of dry periods in the Amazon basin limits the ability of terrestrial frogs to reproduce successfully, while in Central America a more benign dry season, while strong enough to create distinct seasonal trends in the phenology of rainforest animals, is not strong enough to prohibit frogs from recruiting juveniles during the dry season.

The Editors are pleased to report that the Journal of Zoology had another successful year in 2001. The submission of high-quality papers has continued to increase in numbers, and although these are most welcome, it means that far more papers are received than we are able to publish. We therefore have to make hard decisions about the selection of topics to be covered and we have to keep a balance between vertebrate and invertebrate taxa. In August, it was agreed that the focus of the Journal should be re-directed to the publication of hypothesis-driven research that is of interest to the general reader in zoology. Although we will continue to publish original research and reviews within the whole field of zoology, and provide information on the latest trends and developments, papers on the systematics of a restricted number of taxa, or on topics of specialist interest only, will not normally be accepted. We have also introduced a mechanism for accelerated publication for papers that are considered to be of topical interest or those that describe innovative research.