Adult annual survival rates estimated by mark–recapture for eight Greek populations of the tortoise Testudo hermanni were in the range 0.80–1.0 (mean 0.886). Estimates from growth rings for the same populations were in a similar range (0.84–0.95, mean 0.899). The average survival rate from the two methods was significantly positively related to mean adult body size (r=0.815) and negatively related to effective temperature (r=−0.880). A life table model was used to investigate the consequences of adult survival rate for optimum age at maturity and mean adult size of females. The basis of the model was the trade-off between increased reproduction from large adult size, and decreased survival to maturity from delayed age at maturity. The model showed that the observed variation in adult survival rates was more than sufficient to account for the variation of adult size among populations. The model thus predicted an even greater range of mean adult size than that observed. A negative correlation between growth rate and adult survival rate or age at maturity, as observed, was needed to fit the size data. The model supports the hypothesis that variation in adult size of T. hermanni in Greece is adaptive (rather than a non-adaptive environmental or phylogenetic effect) and due to variation in adult survival rates (rather than other factors such as juvenile survival).

Wood mice Apodemus sylvaticus are potentially useful indicators of change in arable ecosystems. Here we focus on changes resulting from removal of land from arable production under the set-aside scheme. Wood mice were radio-tracked to compare: (a) their use of set-aside, crop and hedgerow before and after harvest; (b) set-aside configured as margins and as a 3 ha block; (c) cut and uncut 20-m wide set-aside margins. Males had larger home ranges, and were more mobile than females. Ranges were larger, and animals more mobile, before harvest than afterwards. There were no differences in range sizes of breeding and non-breeding animals after harvest, suggesting that changes in habitat use were not a function of cessation of breeding. Before harvest, wood mice used habitats within their ranges at random, and their ranges contained a high proportion of cropped area. After harvest they preferred hedgerow and avoided margin set-aside within their ranges, but did not similarly avoid the set-aside block. The proportion of cropped area within their ranges decreased after harvest, and the proportion of margin increased. Our evidence suggests wood mice avoided using the area adjacent to the hedgerow, perhaps to avoid predators. Uncut set-aside patches were favoured and cut patches avoided, possibly in response to differences in food availability and levels of protection from predators. These results confirm that wood mice are useful indicators of change in arable landscapes.

Studies of the grey seal Halichoerus grypus mating system, using focal animal sampling constrained by study site location and size, limit the measurement of variation in male mating tactics and success. Using this method, the mating tactics of grey seal males have been classified as either ‘tenured’ or ‘transient’. Preliminary evidence is presented of wider variation in male mating tactics and success using mobile focal-animal techniques that are not constrained by site, and of the effects of age on behaviour when accounting for body mass. The study was conducted during the breeding seasons of 1997 and 1998 at Sable Island, Nova Scotia. Six young (11–12 years) and five old (20–25 years) males were captured at the beginning of the breeding season, weighed and fitted with a VHF transmitter and time-depth recorder. Each male was located daily, and a count of late-lactating females within a 10 m radius recorded as a measure of mating potential. Female guarding and observed copulatory attempts were used as a measure of mating success. Mean initial body mass of young males and old males was similar, 291 ± 13 kg and 298 ± 14 kg, respectively. All males changed location during the study period. Young males changed sites more often and moved shorter distances between sites than old males. Estimated mating success varied from probably no matings to a minimum of seven; there were no differences between young and old males. Maximum duration of stay at a site and the number of late-lactating females at a site significantly influenced mating success. All the males except for two young males departed on diving excursions during the breeding season and engaged in deep diving behaviour. Diving behaviour did not differ between the age classes. Our results indicate that the current classification of mating tactics in grey seal males is an oversimplification. Preliminary data show that age may account for some of the variation in male behaviour on land and mating success, but not for behaviour at sea.

Phenotypic evolutionary rates are reported for cranial characters of eight species of large-bodied Neotropical marsupials: Didelphis aurita, D. marsupialis, D. albiventris, Philander opossum, P. frenata, Lutreolina crassicaudata, Chironectes minimus, and Metachirus nudicaudatus. These rates were found to be lower than expected if cranial diversification in these opossums had occurred by mutation and genetic drift only, and it is clear that a greater diversification was prevented. As all parameters used in estimating rates were very conservative, the conclusion that stabilizing selection has predominated during the evolution of the skull of large-bodied opossums is fairly robust. We also show that directional selection sustained for 150 generations (158 years) or less is capable of producing differences of the same magnitudes as those found between various pairs of species. Therefore, we conclude that even where a particular differentiation has been caused by directional selection, neutral rate tests are unlikely to infer it. This is because following a morphological shift, stabilizing selection will progressively erase evidences of directional selection.

Infestation of marsh tit (Parus palustris, Paridae, Passeriformes) broods by bloodsucking larvae of Protocalliphora falcozi Séguy 1928 (Calliphoridae, Diptera) was studied over an 8-year period in a population breeding in natural holes, in the primeval forest (Białowieża National Park, eastern Poland). Overall 54% of 222 marsh tit nests were parasitized. Prevalence (27–88%) significantly changed across years. This variation did not depend on the timing of the marsh tit breeding season, or winter/spring temperatures. Frequency of infestation did not depend on forest type or hole attributes. Infestation intensity was rather low (median 8, max. 75 flies/nest, 85% of nests with <3 flies/young). Intensity and prevalence were weakly, but positively, correlated. Larger broods contained significantly more blow flies, but per nestling load did not depend on brood size. No effect of infestation on nestlings was recorded – their mortality did not increase, nor was fledging delayed. In response to the presence of blow flies, parents apparently attempted to increase their feeding rate. There was a clear reproductive cost: 60–63% of female and 68–69% of male marsh tits that had none up to eight blow flies, survived to the next spring, but only 34% of females and 44% of males with more than eight flies/brood did so. It is suggested that the small clutch size of marsh tits could have evolved, inter alia, to reduce the fitness costs of ectoparasites.

In lowland England, badgers Meles meles form social groups of up to 30 individuals. They share a main den (sett) and a core feeding range, but largely forage alone. Faeces are deposited in discrete hinterland and border ‘latrines’. Border latrines are shared with neighbouring groups. We demonstrate that there is a highly significant tendency for neighbouring groups to place a similar quantity of faeces at shared latrines. There are also significant tendencies to place more faeces in boundary latrines close to the sett, and for reduced separation of latrines close to the sett. We also demonstrate that badgers tend to defecate most frequently on the boundary closest to their current feeding site. These observations are consistent with the hypothesis that faeces at border latrines are used to promote range exclusion. We propose that faecal volume represents a reliable signal of the encounter likelihood and/or foraging pressure of badgers along a particular border. According to the ‘active territorial defence’ hypothesis, this indicates a stand-off position in terms of each group's resource holding potential by signalling encounter likelihood across the boundary. By the ‘passive range exclusion’ hypothesis, this border is an isopleth (equal contour) of resource depletion between groups, and crossing over such a contour deep into a neighbouring range reduces foraging efficiency. By either hypothesis, the matched faecal volume and sett proximity effects suggest a simple mechanism that is capable of allowing reliable information to be passed by individuals between adjacent sectors of neighbouring territories to deter intrusion. This is a ‘bottom–up’ process of inter-dependent, parallel, individual responses, which is capable of generating the emergent complexity of co-ordinated group ranges without central control.

Bridled nailtail wallabies Onychogalea fraenata are endangered, medium-sized, nocturnal macropodids that persist at only one location in central Queensland, Australia. Characteristics of juvenile development, shelter use, anti-predator behaviour and maternal care were investigated in the wild using trapping, radio-tracking and spotlighting observations. Timing of developmental stages was identical to the pattern previously found in captivity, except for age at weaning which was much earlier in the wild. After young had left the pouch permanently at 17 weeks of age and weighing c. 800 g, they always spent the day concealed in dense cover, generally >200 m from their mothers. Juveniles were also alone in >50% of observations at night, and stayed closer to cover than did adult females. Young became independent of their mothers 7–8 weeks after permanent exit from the pouch and weighing c. 1800 g. Females with dependent juveniles changed their behaviour in ways likely to reduce predation on young. They reduced their home ranges, stayed closer to cover and became more wary than other females. Juveniles differed from adult females in their habitat use, anti-predator behaviour and shelter site preferences. Juveniles were more likely than adults to respond to threats by standing still or lying flat on the ground, whether or not they were in concealing cover. Juveniles used a wider range of smaller shelters than adults, and were less likely to use solid shelters such as hollow logs during the day. Because bridled nailtail wallabies have a ‘hider’ strategy of maternal care and the young rely on crypsis, successful breeding in the wild requires dense vegetation cover.

The commonly reported freshwater snail Ceratophallus natalensis (Krauss) (Planorbidae) of eastern and southern Africa is shown here to be a composite taxon comprising at least three species. The species of Ceratophallus are found only in Africa and some Indian Ocean islands; they are distinguished by the structure of the penis, which is chitinized internally and may bear microspination. Ceratophallus natalensis (Krauss) has been often recorded as common in pools and marshes. According to observations on the genital organs reported here, this taxon comprises three species, C. natalensis, C. gibbonsi (Nelson) comb. nov. and C. yesimit sp. nov. No clear-cut conchological differences among them were evident. Anatomical observations were made on snails from 398 collectors' samples, providing many new locality records for this genus (details in Appendix). Ceratophallus natalensis and C. gibbonsi are widespread from Ethiopia to South Africa, whereas C. yesimit is known only from the Ethiopian Rift Valley. Though natalensis and gibbonsi are partly sympatric, the latter is associated with fully tropical climatic areas and comparatively permanent waterbodies, whereas natalensis is commonest in cooler areas and is abundant in seasonal rain pools. This study showed the penis of Ceratophallus to be stiffened by internal chitinous bands that apparently are unique in the Planorbidae and perhaps for all pulmonate molluscs. It is suggested that the microspinous penis of C. natalensis may be adapted to the function of sperm displacement. The chromosome number 2n=36 was observed for C. natalensis. Comparative data are given for Afrogyrus coretus (de Blainville) (Planorbidae), which in part of its range is sympatric with Ceratophallus and has a similar shell, but differs in having an external penial stylet. Although both groups are found only in the Afrotropical Region, they apparently differ in biogeographical history and phylogeny. In a cladogram where the first apomorphy is external chitinization of the penis, Afrogyrus is allied to Gyraulus, whereas Ceratophallus is more closely related to Planorbis.

The red fox Vulpes vulpes is usually classified as being territorial, dispersing or transient. Past studies have focused almost exclusively on territorial or dispersing foxes, leaving transient foxes out of the analysis. In this paper, we present spatial-statistical methods for the classification of free-ranging foxes, using 95% fixed kernels and 100% minimum convex polygons. By means of these procedures we classify individual foxes on the basis of their spatial behaviour, using home-range size and home range shift. Also, we make a methodological comparison between these classification procedures and interpret the composition of these classes ethologically. The procedures apply to a sample of 24 foxes, radio-tracked in the dune area of the Netherlands from January 1997 to June 1999. We analysed size of home range and successive 3-month overlap using a geographical information system (GIS). Classifying the sample using 95% fixed kernel home ranges resulted in two classes of foxes: a class of 20 territorial foxes with relatively small home ranges (<250 ha), and a class of four dispersing and transient foxes with relatively large home ranges (400–600 ha). This study shows that a fox population can be divided into different classes of individuals in a quantitative statistical way, honouring measured characteristics. This is a clear extension of more informal ways relying on expert judgement applied so far.

Most species of birds of paradise (Paradisaeidae) are endemic in the rainforests of New Guinea. There are also a few species in the northern Moluccas and in northern Australia. Bowerbirds (Ptilonorhynchidae) are centred in New Guinea but are more widespread in Australia. The two families have often been regarded as sister groups, but in recent studies Paradisaeidae appear as sister to Corvidae, a worldwide family which is notably depauperate in New Guinea and Australia. This indicates vicariance of a worldwide ancestor, rather than invasion of New Guinea. Other families in the superfamily Corvoidea include Ptilonorhynchidae (basal), Campephagidae (Africa to New Guinea and Fiji), and Cracticidae (Australia to New Guinea). Biodiversity levels in Paradisaeidae and Ptilonorhynchidae were assessed from literature records by counting numbers of species in grid cells 1° latitude by 1° longitude. Birds of paradise are equally diverse in the Mendi square and the Mount Hagen–Wahgi Valley–Jimi Valley square. Bowerbirds are most diverse in the Mount Hagen–Wahgi Valley–Jimi Valley square. This area lies on one of the main tectonic boundaries in New Guinea, the former margin of the Australian craton, and is geologically distinctive in having several diverse accreted terranes juxtaposed there, including an ophiolite complex. It also includes the western slopes of Mount Wilhelm, one of the highest mountains in the New Guinea orogen. Paradisaeidae have secondary centres of diversity in the southern part of the New Guinea orogen (south of the former craton margin), while Ptilonorhynchidae have secondary centres north of the craton margin on the accreted terranes, and also in eastern Australia. Within New Guinea the two distributions correlate closely with the geological interpretation of the orogen as comprising southern (craton) and northern (accreted terrane) components. Within Australia, Paradisaeidae have two species per degree square in northern Cape York Peninsula (on the old Australian craton), and only one elsewhere in eastern Australia, whereas Ptilonorhynchidae have a clear Australian massing further south in Queensland, on the accreted terranes of the Tasman orogen.

One of the hypotheses proposed to account for why badgers Meles meles are highly social in the U.K., the resource dispersion hypothesis, is that patchy resources are unpredictably dispersed in the environment and therefore must be shared, but that these patches are rich enough, when available, to support several badgers at any one time. Previous empiricists in our study site at Wytham Woods calculated that single patches could be rich enough to support 30 badgers in a night. The sustained increase in population density in Wytham Woods suggests that food was not limiting and territories were below capacity, and therefore that feeding competition was relatively low. Low feeding competition would predict an absence of dimorphism in trophic apparatus between the sexes. Contrary to this, significant sexual dimorphism was found, after removing effects resulting from body size allometry, in canine cross-section length, width (both P < 0.0001) and skull breadth (P < 0.001). The differences in canine dimensions were still significant when allometry of both body length and skull breadth are accounted for statistically (P < 0.0001). It is therefore suggested that feeding competition may not necessarily be low, which would have implications for understanding the costs of social behaviour. Alternative explanations involving sexual selection and phylogenetic inertia are discussed.

This paper provides the first account of merycism in koalas (Phascolarctos cinereus), and in doing so, potentially sheds new light on the occurrence and significance of this behaviour in other herbivorous marsupials. Koalas fitted with acoustically sensitive transmitters, to monitor mastication and ingestive behaviour, were also found to make bouts of rhythmic ‘mastication-like’ noises that were not associated with ingestive feeding events. On average, these bouts consisted of 9.16 ‘mastications’, at an average rate of 1.21 ‘mastications’ per second, and occurred 53.3 times throughout a 24-h period. Furthermore, bouts were usually preceded by, and always followed by, a series of ‘creaky’, guttural noises that were interpreted as regurgitation and re-swallowing, respectively. Merycism may allow koalas to periodically re-masticate gastric digesta, while in a resting position, and thus potentially save energy and increase the extent of food preparation. Consequently, merycism may contribute to the koala's ability to consume a high fibre, poor quality diet.

Repeated measurements of captive-born Gaboon vipers Bitis gabonica from an inbred stock examined the degree to which an animal's size and shape are affected by food intake. We also used the level of asymmetry in dorsal coloration as an index for possible genetic (inbreeding?) effects. Both of these factors, and the interaction between them, affected phenotypes of the young snakes. Snakes raised with abundant food differed from their less well-fed siblings not only in size, but also in body mass relative to snout–vent length, head length relative to snout–vent length, head width relative to head length, and fang length relative to jaw length. Hence, our data show that body proportions (including the feeding apparatus) can be influenced by the environment after birth.

Annual local survival of the garden dormouse Elyomis quercinus, a small, hibernating rodent, was studied by Cormack–Jolly–Seber models. The survival rates differed significantly between the 4 years of the study; the average rate was 0.38 (95% confidence interval: 0.25–0.52). Survival rates were not significantly different between sexes. Because all garden dormice were captured after weaning, pre-weaning survival could not be estimated. After weaning, the annual survival rates did not differ between age cohorts. In order to find out which phases within the annual cycle were more prone to mortality, survival was studied on a bimonthly scale as well. Survival during hibernation was estimated to be close to unity, while survival during the active phase of life in summer was considerably lower. The winter temperatures of the study years were similar to the long-year average; thus garden dormice were well adapted to these average conditions. Although hibernation is energetically challenging, it is not necessarily accompanied by increased mortality, as found in other studies focusing on survival during hibernation.

A 20-year study of a common toad Bufo bufo population in south Dorset, U.K. was carried out between 1980 and 1999. On average, c. 33% of all experienced males and females arriving each year did so during the first quarter of each breeding season with only 18% arriving during the last quarter. Conversely, a slightly higher proportion (27%) of all inexperienced (first-time breeders) males and females arrived during the last quarter season than during the first quarter (22%). In 18 of the 20 years, the proportion of inexperienced females found paired with inexperienced males was significantly higher than could be expected from the proportion of inexperienced males in the pond, suggesting that selective pairing was occurring. One potential effect of pairings between inexperienced male and female toads, coupled with the sex difference in the age of attaining sexual maturity, might be a reduction in the incidence of sibling matings (inbreeding) in the common toad. This is particularly relevant in a species that is both highly philopatric and which congregates in large numbers every spring to breed in very localized areas.

This study examined the foraging locations of lactating female and pre-breeding adult male South American sea lions Otaria flavescens in the Patagonian continental shelf, south-west Atlantic ocean. Research on females included the diving pattern, and was conducted during the 1994–98 breeding seasons in five northern and central Patagonian rookeries. Twenty females were satellite-tracked using the Argos system and yielded 1558 locations at sea. Satellite transmitters were also deployed on two adult males tracked for a total of 94 days (n = 364 locations) before the onset of the 1999 breeding season. Foraging trips for both sexes were confined to the temperate waters of the Patagonian continental shelf although males travelled greater distances than females, and arrived close (c. 80 km) to the edge of the shelf. Females from the same rookery dispersed widely and locations at sea often overlapped. Individual differences were apparent between coastal and pelagic animals. Trips lasted a mean of 3.4 days (sd = 1.3, n = 115 trips). Mean travel distance per trip was 206 km (sd = 117 km, maximum 864 km, n = 115 trips). Females reached further distances by travelling faster rather than by extending the duration of trips. Consistent with the shallow continental shelf, 65% of 75 087 dives recorded for nine animals were in the range of 2–30 m. Males alternated periods on the coast with trips to sea lasting a mean of 5.7 days (sd = 3.0, n = 8 trips). Mean travel distance exceeded 591 km (1 sd = 301 km, n = 8 trips). Results are consistent with sex differences reported from diet studies. Locations overlap with the summer operation of shelf fisheries targeting species that are also part of the sea lion diet.

In this study the predation and fish prey selection of otters Lutra lutra L. living by eutrophic fish ponds on agricultural land and in a protected area of temperate climate in Hungary were investigated. The correlations between fish in the diet of the otters (by spraint analysis involved 1942 and 1280 samples for the two habitats) and the fish stock available (by harvest and sample fishing) were generally close. Prey selection was significantly related to selected species of a particular size range (P<0.01). The preference calculations were performed with Ivlev's index of preference (Ei, minimum −1, maximum +1). Regardless of species, the otters avoided (Ei=−0.51) fish heavier than 1000 g, with a preference for individuals weighing between 500 and 1000 g (Ei=0.79). No substantial or clear preference was observed in the weight range below 500 g (Ei=−0.02–0.38). The preference for fish in accordance with their characteristic sites of occurrence within the body of water was also significant (P<0.01). They avoided fish living primarily in open water (Ei=−0.64) and to a lesser degree those occurring near the pond bed (Ei=−0.22). They favoured fish inhabiting the area with a covering of aquatic plants (Ei=0.46), and showed a preference to a lesser degree for fish living in the shallow littoral regions (Ei=0.14). With the cessation of fish farming and the effect of the drastic changes which occurred in the vegetation, the otters fed substantially on the stock of alternative sources of prey such as amphibians and water insects as well as terrestrial animals, and at such times, depending on season, fish became a secondary source of prey.

A new representative of the thus far monotypic, Bermudan aselloid family Atlantasellidae is described from the freshwater layers of two coastal sinkholes on the south-west Dominican Republic, Hispaniola. Atlantasellus dominicanus sp. nov. is extraordinary among isopods in retaining a remnant of the exopod on one of its pereiopods; no other isopod is known to express a schizopodous condition of thoracic limbs. The locomotory behaviour, body volvation habits, and apparent specificity of the new taxon for life on submerged decaying wood in cave waters are described. Analysis of palaeogeographic and ecological evidence supports the interpretation of the Atlantasellidae as a thalassoid lineage, contrary to previous phylogenetically supported assumptions considering them to be an ancient, freshwater lineage.

We studied the intraspecific interactions among oophagous Chirixalus eiffingeri tadpoles that occupied the same water-filled bamboo stumps at Chitou, Taiwan. We monitored the growth of newly-hatched tadpoles in unoccupied and occupied bamboo stumps in the field where the latter contained large tadpoles that hatched from earlier clutches. The growth of the small, late-hatching tadpoles in occupied nests was suppressed by the presence of large, early-hatching tadpoles. However, small tadpoles that were physically separated from large tadpoles in a perforated container grew at about the same rate as small tadpoles living in pools without large tadpoles. Thus, the slower growth of the late-hatching tadpoles was probably caused by behavioural interference competition with the early-hatching tadpoles. In the laboratory, we kept large and small tadpoles together in containers and did not feed them for 6 days. The large tadpoles did not cannibalize the small tadpoles. Although large tadpoles may scavenge dead tadpoles, the effects of scavenging on growth were negligible. Interactions among cohabiting C. eiffingeri tadpoles are similar to those among the oophagous tadpoles of several hylid species that use phytotelmata. Results suggest that behavioural interference competition is the principal type of intraspecific interactions among the oophagous, non-predatory tadpoles of hylid and rhacophorid frogs.

Primate quadrupeds are said to use relatively large limb excursions for mammals of their body size. Until recently, this claim was based on a comparison of hindlimb excursion data derived from small samples of primates and non-primates. Using video recordings collected at zoos and primate research centres, the present study documents this contrast on much wider samples of quadrupedal mammals. The results indicate that while on average hindlimb excursion is relatively larger in quadrupedal primates, this contrast is somewhat less dramatic than first reports suggested. Comparisons between the data reported here and previously collected forelimb excursion data reveal a surprising asymmetry between the fore- and hind excursions for most mammalian species. Most commonly, forelimb excursion exceeds that of the hindlimb. We suggest that this is related to a complementary asymmetry in limb length (forelimbs shorter than hind) for the purpose of achieving equal step lengths for both pairs of limbs. Relatively large hindlimb excursions in primates have been related to a mechanism that reduces stresses on the forelimbs and then recovers mechanical energy during gait. We suggest that large excursions of both the fore- and hindlimbs are linked to other alterations in gait parameters, such as step length, contact time, and limb compliance, that have been adopted in quadrupedal primates to facilitate locomotion along slender arboreal substrates.