Adult female survival as a potential proximate factor responsible for observed changes in southern elephant seal Mirounga leonina populations was investigated. We compared the survival rate estimates from mark–recapture data for female elephant seals from the Marion Island population (using program MARK) for two periods (pre- and post-decline) during the past 15 years and with estimates from another population in southern Argentina, which had increased steadily during the same period. Survival of prime-age adult females increased significantly by 6.2% during the latter part of the decline at Marion Island, and the survival of adult females at the colony in southern Argentina was 3.2% greater than at Marion Island after the stabilization. We thereby demonstrated the importance of adult female survival in population regulation and emphasized the importance of monitoring adult females in order to understand population changes in southern elephant seals. In addition, we investigated whether reproductive expenditure early on in life reduces future reproductive potential in the population at Marion Island. We did this by estimating and comparing future survival and breeding probabilities of females primiparous at different ages. The future annual survival and breeding probabilities of females breeding at a young age, was similar to those from females primiparous at an older age. There was also no reduced survival in the year following first breeding in young or older first time breeders. Reproductive expenditure in young primiparous females therefore did not entail future fitness costs relative to older primiparous females, and we found no evidence supporting the existence of various life-history strategies in terms of age of primiparity within a population of southern elephant seals.

Genetic differentiation among populations of the South African scrub hare Lepus saxatilis was examined using hypervariable mitochondrial DNA control region I (CR-I) sequences. Neighbour-joining analysis revealed a pattern that did not correspond to the current subspecies delineations. The CR-I sequence data delimit scrub hares into three major maternal lineages. The three phylogenetic assemblages exhibited different geographical distributions. AMOVA analyses and exact tests for population differentiation confirmed this phylogeographic partitioning. One lineage (SW) was confined to the south-western Cape, the second lineage (N) was exclusively found in the northern part of South Africa and in the neighbouring countries, and the third lineage (C) was predominant in the central parts of South Africa. This spatial distribution did not coincide with the ranges of the 10 described subspecies covered by our sampling regime. The lineages C and N overlapped in an area including eastern parts of South Africa and southern Namibia. The presence of both lineages in that area of overlap was interpreted as the result of secondary contact due to recent range expansions after the two lineages had undergone a population restriction approximately 18 000 years ago. Analyses of contemporary gene flow disclosed an exchange of migrants between N and C, which was biased towards a movement from C to N. The SW group represents a very distinct evolutionary lineage that has been isolated for more than 45 000 years. It does not exchange female migrants with the other two groups. Mismatch distribution analyses indicated sudden population size expansions in the history of all three populations.

Around the world, endemic species with restricted ranges seem to be at particular risk of extinction. When range size is controlled, lowland continental species may be especially at risk, more so than island or montane species. Our study aimed to investigate reasons behind the high vulnerability of endemic species. In Sri Lanka, large-scale national surveys and intensive localized fieldwork established that endemic plant and animal species are mostly associated with undisturbed rainforest habitats. On the other hand, non-endemic species used both forest and non-forest habitats almost equally, suggesting they are less likely to suffer from deleterious edge effects. To understand the different distribution of endemic and non-endemic species, our study focused on rats. Compared to the widespread species, the endemic rat species had a larger home range and fed on fewer species of forest fruit, possibly indicating greater specialization. The abundance of the endemic species was also negatively correlated with the abundance of the non-endemic species, to which it was behaviourally subordinate. Greater specialization and competitive inferiority could both contribute to the vulnerability of endemic species.

The grey-headed flying fox Pteropus poliocephalus, a nationally vulnerable species, is endemic to coastal eastern Australia, from Maryborough, Queensland, through New South Wales to Melbourne, Victoria. Pteropus poliocephalus forages at night, primarily on eucalypt blossom within 50 km of traditional camps (day roosts), usually in dense, riparian vegetation. Several attempts have been made to track long-distance movements of P. poliocephalus across its extensive and climatically highly variable range, but the technology has been inadequate for tracking at the required speed and scale. Satellite tracking was used to monitor movements of a 2-year-old male P. poliocephalus, trapped at the Currie Park camp in the north of the species' range (28°48′S) from January 2000, and another from its most southerly camp, Melbourne (37°50′S), from April 2000. The first flying fox moved camp 50 km noth-east to Dallas Park, where it stayed until March, then transited at least 15 other camps between 28°12′–32°44′S, before returning to Dallas Park in September. The second flying fox remained in Melbourne until July, then transited at least six other camps to 33°44′S, before returning to Melbourne in January 2001. Both animals made round trips of at least 2000 km, traversing >4° latitude, before returning to their camps of origin, while other animals remained. The study suggests that P. poliocephalus is a partial migrant that uses winds to facilitate long-distance movements, and underlines the importance of management at a national scale.

The phylogenetic relationships within the family Talpidae (Mammalia, Insectivora) were inferred from parsimonious analysis of 55 morphological characters, which were collected from 43 skulls of 22 species, and which included all of the extant genera in the current taxonomy of the Talpidae. Two equally parsimonious cladograms were obtained. The Uropsilinae, Desmaninae and Talpinae subfamilies formed monophyletic clades, and the Desmaninae and Talpinae subfamilies were sister clades. The Talpinae subfamily was subdivided into the following clades: Urotrichus, Dymecodon, Scalopus–Scapanus, Parascalops–Scapanulus, Condylura, Neurotrichus, Scaptonyx and Talpini (Talpa, Euroscaptor, Scaptochirus, Parascaptor and Mogera). The Urotrichini (Urotrichus, Dymecodon and Neurotrichus) and Scalopini (Scalopus, Scapanus, Parascalops and Scapanulus) were considered to be paraphyletic, and were defined primarily by their ancestral characteristics. Since the genus Dymecodon was not clustered with Urotrichus, it was considered to be a valid genus, and not just a junior synonym of the latter. The Asian genus Euroscaptor was found to be a paraphyletic group, and deserves further systematic revision. The evolution from semi-fossorial habit to fully fossorial habit seems to have occurred three times in the Scalopus–Scapanus, Parascalops–Scapanulus and Talpini clades. The migration of the Talpinae to North America from Eurasia probably occurred on four separate occasions in the Scalopus–Scapanus, Parascalops, Condylura and Neurotrichus lineages.

The highveld mole-rat Cryptomys hottentotus pretoriae is a social subterranean rodent that exhibits seasonal reproduction. Non-reproductive females remain anovulatory whilst in the confines of the natal colony. However, during the southern hemisphere summer, dispersal of non-reproductive females from the natal colony occurs with subsequent pairing with unrelated males. This study investigates whether the dispersing female highveld mole-rat is an induced or spontaneous ovulator. Eight non-reproductive females were removed from their natal colonies during the breeding season and housed individually for 5 weeks. Urine was collected every second day during the next 5 weeks of isolation. After this initial period, isolated females underwent one of three trials: two females were kept isolated without a male, three females were individually placed in chemical but not physical contact with unvasectomized males, while each of the remaining three females were allowed full contact with a vasectomized male. Urine was again collected every second day for a further 5 weeks, after which the females were killed. Both urinary progesterone profiles and histology of the ovaries revealed that the female highveld mole-rat is an induced ovulator. Females in physical contact with vasectomized males exhibited a significant increase in urinary progesterone concentration as well as the presence of corpora lutea in their ovaries, both indicative of ovulation. The act of coitus is necessary for ovulation to take place even though the males were not capable of fertilization. This is the first time induced ovulation has been shown in bathyergid rodents.

The relationship between masticatory morphology and chewing modes in all living genera of South American rodents in the family Octodontidae was analysed. Chewing directions and the patterns of molar occlusion were assessed. Factor and regression analyses of skull and jaw characters, and attributes of the adductor musculature, especially the line of action of masseters and pterygoids, were performed to check their relations with the chewing modes. Two basic chewing strategies are present in octodontids: oblique unilateral (associated with anterolingual jaw displacement, and alternate occlusion of left and right molar series), and propalinal bilateral (associated with mostly posteroanterior jaw displacement, and simultaneous occlusion). The skull and jaw characters examined are related only partly to these chewing strategies. The temporal pattern of muscle contraction provides a possible explanation for such a functional versatility. Propalinal grinding in octodontids could be achieved through simultaneous muscle contraction, with limited reliance on the lines of action of the involved muscles. Therefore, simultaneous contraction explains a similar propalinal masticatory mode in morphologically disparate genera. In accordance with phylogenetic information, oblique unilateral chewing is primitive in octodontids, and the derived propalinal mode has been developed independently at least twice in the evolution of the family.

Two hundred and fourteen skulls of Asian deer species (Cervini) were measured and the resulting craniometric data analysed using multivariate statistics. Our results suggest that elements of skull shape as determined by morphometrics can be used as phylogenetic characters and depict phylogenetic relationships among Cervini deer species that is not far removed from the picture given by molecular studies and other characters. Morphometrics-based phylogeny was used in combination with other phylogenies and palaeoenvironmental reconstructions to investigate factors that may have influenced evolutionary changes. Our data indicate the need for a revision of the genus and subgenus level taxonomy of the Cervini.

Enamel hypoplasia, a developmental tooth defect, provides a permanent record of systemic stress during early life. The incidence and distribution of linear enamel hypoplasia has been used by anthropologists and palaeontologists to assess the health status of past populations but has not been applied by wildlife biologists studying extant animals. This study investigates enamel hypoplasia in 23 Giraffa camelopardalis skulls from wild and captive animals of various ages and sex to determine whether any systemic stress events are unique to life in captivity. Results indicate that wild giraffes are relatively stress-free as they do not have linear defects. Based on the distribution of linear defects in other giraffes, three key stress periods during the first 6 years of giraffe life were identified. The first stress event occurs during weaning, the second at about 3 years of age and the third, which is the least common, at 4–5 years of age. All three stress events were observed in both male and female giraffes. This study highlights the usefulness of assessing enamel hypoplasia in both wild and captive animals as well as the need for further research on tooth developmental timings in many wild ungulates. Some left–right asymmetry was observed in the development of linear and non-linear defects, which has implications for the aetiology of these defects.

Dynamics of a rodent community were studied in the Negev Desert Highlands (Israel) during 8 years on 24 permanent 1-ha plots representing six main habitat types. Based on theoretical models of habitat selection, we hypothesized that niche overlap between species of the same spatial guild should increase with density faster than that between species of different guilds. Data were analysed using multivariate (principal component and discriminant) analyses to test the hypothesis. Density changes in most rodent species followed fluctuations in the amount of rainfall. Habitat niche breadth was density-dependent in six species and density-independent in four species. Significant habitat shifts and switches of spatial guild membership were found in three of 10 species. Pairwise values of habitat overlap were significantly and positively correlated with density only in species pairs where both species demonstrated density-dependent variation of habitat breadth. In most other pairs of species, overlap values were density-independent. Comparison of changes in average within-season values of habitat overlap with density within and among spatial guilds directly supported our hypothesis demonstrating faster increase of niche overlap with density between species of the same spatial guild than between species of different guilds.