Long-term continuous observations of hunting lions Panthera leo in the Kruger National Park were used to assess the variables affecting hunting success of male and female lions. Generalized linear models revealed that seven variables had significant independent influences on hunting success, with the most important being the prey species hunted. Three types of variables were recognized: (1) lion related, where type of hunt, wind orientation, and the number of adults hunting; (2) prey related, where prey species and herd size; (3) environment related, where moon brightness, and grass height were significant. The sex of the lions had no effect on the overall probability of hunting success. Five second-order interactions significantly influenced the probability of hunting success, with the most important being the interaction between sex and the type of prey. The only significant third-order interaction containing the variable sex, was the inter-relationship with prey species and shrub cover. After removing the over-riding bias of the prey species, greater resolution of the factors affecting success was revealed. The major difference was that group size influences hunting success and concomitantly prey selection, promoting selection for medium-sized ungulates like zebra Equus burchelli and wildebeest Connochaetes taurinus by females, and males mainly capturing buffalo Syncerus caffer. We conclude that in African ecosystems, the hunting success of male and female lions varies with a range of combinations of lion-, prey- and environment-related variables. We demonstrate the hunting ability of male lions, which has perhaps been understated in other studies.

The following Applications were published on 29 September 2000 in Vol. 57, Part 3 of the Bulletin of Zoological Nomenclature. Comment or advice on any of these applications is invited for publication in the Bulletin and should be sent to the Executive Secretary (I.C.Z.N.), c/o The Natural History Museum, Cromwell Road, London SW7 5BD, U.K. (e-mail: iczn@nhm.ac.uk).

The mahogany glider Petaurus gracilis is an endangered species of gliding possum that is only found within a limited distribution in North Queensland, Australia. The foraging behaviour of the mahogany glider was examined to determine how it changes seasonally, by extensive observations of radio-collared animals over a 2-year period. A total of 440 h was spent following mahogany gliders, of which 222 h of feeding behaviour was observed. Nectar and pollen were clearly the most important food items, comprising between 50 and 99% (mean 72.8%) of the observed feeding time when available. Nectar and pollen were consumed almost exclusively from Myrtaceae species with Eucalyptus, Corymbia and Melaleuca being eaten. Casual observations of a number of faecal samples showed that c. 80% of pollen grains were digested suggesting that pollen is a major source of protein. Other food items consumed included sap from Albizia procera and Acacia mangium, insects, lerps and honeydew, Acacia arils and fruit from mistletoes. In using these food items, the mahogany glider relied on complex seasonal cycles of food availability, requiring a high diversity of plants, with each species having distinct periods when it provides food during the year.

Reproductive activities of six giant panda females (Ailuropoda melanoleuca) living in the Qinling Mountains of China (Shaanxi Province) were recorded from 1989 into early 1995. Data on mating and birth dates, litter size, cub sex and den use were collected for three of the pandas. At this site, pregnant females migrated to lower elevations in advance of other pandas to seek dens for birthing. One dam was videotaped in the den with her cub from birth to the end of the denning phase at 94 days of age. This cub was repeatedly handled during the dam's absences to obtain data on development and weight. During the early part of the denning phase, the cub was maintained on the dam's body virtually continuously. Post-partum fasting for up to 3 weeks was noted. Dams invariably moved cubs to new dens three or four times during the birth season. By the time cubs left the den at about 3–4 months, they were fully furred and capable of surviving winter temperatures without further shelter. Reproductive parameters for the wild population fell within the range of values for captive pandas, based on information in the literature and in the giant panda studbook. The combined data on length of gestation, intervals between births, litter size and weight, infant development, and reproductive life span reveal a range of life-history variables that strongly resemble the Ursidae.

Two new species of terrestrial planarians in the family Geoplanidae, Geoplana franciscana and Notogynaphallia guaiana, from the State of Rio Grande do Sul, Brazil, are described. Both species have a multilayered lining in the female atrium. The study of specimens of N. goetschi, aimed at comparing it to N. guaiana, reveals the need for a re-description and review of N. goetschi.

Two bovid frontlets with horns collected in 1929 and now housed in the collections of the University of Kansas Natural History Museum (KU) from Suoi Kiet, Binh Tuy Province, Vietnam, were previously identified as koupreys (Bos sauveli). We believe that they are specimens of the recently discovered bovid, Pseudonovibos spiralis Peter & Feiler, 1994. The KU specimens are represented by the posterior half of the frontal bones, the parietals, the horn cores and horns, and the anteriormost supraoccipitals, and are the most complete, best documented, and oldest specimens known of this poorly known species. We believe that both an adult male and an adult female are represented. Although the specimens are fragmentary, they still provide significant information that allows us to describe some aspects of P. spiralis, and they are especially critical to our understanding of the relationships of this animal to other bovids. We propose the English name spiral-horned ox, which reflects both its distinctively shaped horns and close relationship to other wild oxen. The Khmer name, Khting Vor, is also an appropriate common name. Previously overlooked references from the 1880s and 1950s document that the spiral-horned ox was believed to have magical powers over poisonous snakes.

Small mammals were sampled in two natural habitats (montane stunted evergreen forests and montane grassland) and four anthropogenic habitats (tea, wattle, bluegum and pine plantation) in the Upper Nilgiris in southern India. Of the species trapped, eight were in montane evergreen forests and three were in other habitats. Habitat discrimination was studied in the rodents Rattus rattus and Mus famulus and the shrew Suncus montanus in the montane forest habitat. Multivariate tests on five variables (canopy cover, midstorey density, ground cover, tree density, canopy height) showed that R. rattus uses areas of higher tree density and lower canopy cover. Suncus montanus and M. famulus use habitat with higher tree density and ground cover and lower canopy height. Multivariate tests did not discriminate habitat use between the species. Univariate tests, however, showed that M. famulus uses areas of higher tree density than R. rattus and S. montanus. Rattus rattus was the dominant species in the montane forest, comprising 60.9% of total density, while the rodent Millardia meltada was the dominant species in the grassland. Studies of spatial interaction between these two species in habitats where they coexisted showed neither overlap nor avoidance between the species. Rattus rattus, however, did use areas of lower ground cover than did M. meltada. The analysis of spatial interactions between the species, habitat discrimination and use, and the removal experiments suggest that interspecific competition may not be a strong force in structuring these small mammal communities. There are distinct patterns in the use of different habitats by some species, but microhabitat selection and segregation is weak. Other factors such as intraspecific competition may play a more important role in these communities.

The takahe (Porphyrio mantelli) is an endemic New Zealand avian species which was once thought to be extinct. Its rediscovery in 1948 heralded an intense species recovery programme, which is ongoing. Early in this programme, difficulties in the assignment of sex became apparent. Subsequently several approaches have been used in order to develop accurate methods to identify males and females in this species. We discuss the value of these approaches and report the results of our studies into DNA-based, as well as morphometric and hormonal methods. We demonstrate that sex-linked DNA sequence variation within both the chromo-helicase-DNA binding (CHD) and ATP synthase α-subunit, (ATP5A1) genes allows the correct assignment of known-sex adults. We also report the development of a discriminant function using body weight, bill depth, shield width, length from nares to bill-tip, tarsus length, mid-toe length and culmen length. This method had a maximum accuracy of 89% on a sample of 37 known-sex takahe, using culmen and tarsus lengths. In relation to hormonal methods of sexing takahe, plasma testosterone and oestradiol concentrations in adult and juvenile male and female takahe were measured in spring. The oestradiol/testosterone ratio discriminated between all 15 adults sampled within 38 min of capture. However, males experiencing increased capture stress had reduced testosterone levels and hence an uninformative oestradiol/testosterone ratio. Testosterone and oestradiol levels were generally undetectable in juvenile takahe less than 10 months old. Consequently, plasma sex steroid analyses in the breeding season are useful for the determination of sex in recently captured adults only.

The anatomy and histology of the thymus in monotremes and marsupials were revisited and several new observations made. Tissues of the mediastinum and/or ventral neck of 134 animals altogether (12 Australian marsupial and monotreme species) were examined and the locations of thymic tissues documented. Descriptions not previously recorded include the gross anatomy of the thymus in monotremes, the bandicoot (Isoodon macrourus, Isoodon obesulus), the wombat (Lasiorhinus latifrons), and koala (Phascolarctos cinereus), as well as light and electron microscopic features in all species examined. In monotremes, thymic tissue was diffusely spread in the mediastinum and extended over the ventral surface of the pericardium. In the bandicoot, a small, deep cervical thymus was persistently present as well as the expected thoracic thymus and contrary to previous observations, a thoracic thymus was found in the wombat but not the koala. Both species also have a cervical thymus. In the marsupial species examined, additional thymic tissue was often present in the vicinity of the carotid bifurcations, in the deep ventral regions of the neck. In many animals, thymic tissue of deep cervical origin as well as thoracic thymus was mingled with parathyroid tissue. In several specimens, the two tissue types lacked intervening connective tissue barriers and at the electron microscopic level, attenuated processes of epithelial reticular cells were the only tissue components separating parathyroid and thymic tissues. The role of the cervical thymus in diprotodont marsupials remains to be elucidated. The presence of aberrant thymic tissue in marsupials is important in the interpretation of experiments involving thymectomy and immunological development because complete removal of thymic tissue may not occur. One aspect that has received little attention is the function of the thymic epithelial reticular cells in marsupial development and a suggestion is made that perhaps the extra thymic tissue found in marsupials provides extra epithelial reticular cells necessary for the production of cytokines and other secretions to sustain the development of immunological competence.

Temporal and spatial distribution of the chiton Acanthopleura japonica and associated molluscs were recorded on a semi-exposed tropical rocky shore in Hong Kong over 24 months. Most molluscs showed a clear vertical distribution pattern which varied with season. Many mobile gastropods, e.g. Monodonta labio, Cellana toreuma, Nerita albicilla and Thais clavigera, were found lower on the shore in summer (June–September), presumably as a response to the hot, desiccating conditions, but extended their range during winter (December–March). Acanthopleura, was distributed throughout the eulittoral and did not show such strong seasonal patterns, possibly due to the ability to use spatial refuges (specifically crevices) as a result of its flexible body-plan. Chitons exposed on horizontal rocks lost more body water during periods of emersion as compared to those in vertical or crevice habitats and, in summer, all animals on horizontal surfaces died. It is suggested that A. japonica uses cracks and crevices, which are not available to hard-shelled molluscs, throughout the year to reduce the impact of heat and desiccation stress during periods of emersion. This ability may explain the slight seasonal changes seen in Acanthopleura as compared to other species, and the dominance of chitons as herbivores on tropical shores.

Time-expanded and heterodyned echolocation calls of the New Zealand long-tailed Chalinolobus tuberculatus and lesser short-tailed bat Mystacina tuberculata were recorded and digitally analysed. Temporal and spectral parameters were measured from time-expanded calls and power spectra generated for both time-expanded and heterodyned calls. Artificial neural networks were trained to classify the calls of both species using temporal and spectral parameters and power spectra as input data. Networks were then tested using data not previously seen. Calls could be unambiguously identified using parameters and power spectra from time-expanded calls. A neural network, trained and tested using power spectra of calls from both species recorded using a heterodyne detector set to 40 kHz (the frequency with the most energy of the fundamental of C. tuberculatus call), could identify 99% and 84% of calls of C. tuberculatus and M. tuberculata, respectively. A second network, trained and tested using power spectra of calls from both species recorded using a heterodyne detector set to 27 kHz (the frequency with the most energy of the fundamental of M. tuberculata call), could identify 34% and 100% of calls of C. tuberculatus and M. tuberculata, respectively. This study represents the first use of neural networks for the identification of bats from their echolocation calls. It is also the first study to use power spectra of time-expanded and heterodyned calls for identification of chiropteran species. The ability of neural networks to identify bats from their echolocation calls is discussed, as is the ecology of both species in relation to the design of their echolocation calls.

The brine shrimp Artemia, a typical inhabitant of hypersaline environments and characterized by a highly subdivided population structure, was used as a model to evaluate, under standardized laboratory conditions (at 65 ppt), primary reproductive traits (offspring quality and quantity) along with levels of reproductive isolation and degrees of divergence among populations. Intrapopulation experimental crosses and cross-fertility tests were evaluated in five populations (mostly A. franciscana) from coastal and inland environments in Chile, and in reference samples of A. franciscana (San Francisco Bay, U.S.A.) and A. persimilis (Buenos Aires, Argentina), which are the species likely to be found in Chile. The populations compared displayed significant variability in fecundity (total offspring, brood size) as well as in the ratio encystment/oviviparity. Hybrid offspring, produced abundantly in cross-fertility tests with reference populations, showed a pronounced switch to the encystment mode, particularly in crosses with A. persimilis. Exposure to a broad range of ecological conditions seems to have optimized a generalist reproductive strategy in the Artemia populations studied that combines variation in both the quantity and quality of zygotes. Laboratory cross-fertility tests evaluated prime reproductive characteristics in individual crosses with fair repeatability, as well as testing barriers to laboratory reproductive isolation. The lack of efficient mechanisms for reproductive isolation in the allopatric Artemia populations studied follows a trend often seen in other anostracods. Formerly allopatric populations have not achieved sympatry later as required by the allopatric speciation paradigm, and this is a probable explanation for production of the laboratory hybrids.

Morphological modification of the cetacean vertebral column for axial locomotion was one of many changes that occurred during and after the invasion of aquatic habitats by the ancestors of living whales. These modifications resulted in a column that can be divided into neck, chest, torso, and fluke structural and functional units. Variations in these units allow subdivision of living whales into three morphological groups that reflect differences in regional flexibility of the column and of locomotor style. Both odontocete and mysticete cetaceans exhibit trends toward reduction of relative centrum length in the neck and torso, restricting the flexibility of the column with increasing adaptation to aquatic lifestyles. Mysticetes and physeterid odontocetes retain the archaeocete pattern of constant vertebral shape along the torso, which acts as an undulatory unit. The location of secondary sites of reduced centrum length in non-physeterid odontocetes subdivides them into subgroups, one with reduced posterior, and the other with reduced anterior, torso flexibility. The relationships between particular osteological patterns and swimming styles in living taxa are used to support predictions of swimming style in fossil species after adoption of a fluke in the late Eocene.

The pattern of home-range use by seven groups of tufted capuchin monkeys Cebus apella nigritus is described in the Iguazú National Park, Argentina, during 1991–94. The seasonal changes in home-range use by one of these groups between August 1997 and December 1998, are correlated with changes in food distribution and availability. Fruit availability was estimated with fruit traps, and the abundance and distribution of food was experimentally changed within the home range of one group by using feeding platforms filled with bananas. Average home-range size is 161 ± 77 ha (range = 81–293 ha, n = 7). There is a positive relationship between the number of females per group and home-range size. Neighbouring groups have partially overlapping home ranges and aggressive relationships. Fruit abundance is scarce during the winter and peaks during the spring and early summer. The pattern of home-range use by the main study group of capuchins was consistent with the hypothesis that fruit distribution and availability is the most important factor affecting the spatial use of their range. This is evidenced by the changes in range size and in range use as the distribution and abundance of their main fruit sources change seasonally. Range use shifted dramatically during the experimental phase of this study; the capuchins reduced their range and most frequently visited the areas where the feeding platforms were located. For most populations of frugivorous monkeys, fruit distribution and availability are the main factors that determine the pattern of home-range use. However, in some populations the availability of water sources and sleeping sites can have some effect on range use. For capuchin monkeys in particular, within-species variation in home-range size, degree of range overlap and interactions between neighbouring groups are large and do not serve to characterize any species of Cebus monkeys.

The integrative patagial morphology of Draco volans was examined to elucidate the possible evolutionary pathway of origin of active patagia in the flying dragons and in extinct taxa that are thought to have possessed similarly constructed flight membranes. The area of the patagia and accessory aerodynamic surfaces is compared between Draco volans and Ptychozoon kuhli, a gekkonid with passive patagia. Comparisons of patagial area are also made between selected species of Draco. Scale architecture of the patagium of Draco is described and is related to pertinent aspects of the structure and properties of the integument. The relationships of these characteristics to the morphology of the ribs and their related musculature are emphasized. The overall assessment of these features in relation to patagial form is employed to develop an evolutionary scenario for the origin of active patagia.

While mating behaviour in onychophorans has been documented in only a few species, it would appear that male reproductive strategies include both dermal and vaginal insemination. To add to this diversity, the males of many newly described species of Australian onychophorans display elaborate head structures. In some species, these head structures have been shown to carry spermatophores. Here we describe Florelliceps stutchburyae gen. nov., sp. nov., a species possessing a unique head structure. An account of its unusual mating behaviour is provided in which the male's everted head structure was placed against the female's gonopore and held there by the claws of the female's reduced last pair of oncopods. After the individuals separated, the female's genital opening was covered by a spermatophore and histological sections showed that sperm had been released into her reproductive tract. A review of mating behaviour in onychophorans is also included with a discussion of sperm acquisition by the female and its correlation with her reproductive cycle.

In this study, the axial skeleton of 14 species of tupaiids (tree shrews) was analysed functionally and compared to that of other archontan mammals. Several differences that relate to differential substrate use were found in the ribs and vertebrae. These differences included cranio-caudal width of the ribs; number of thoracic, lumbar, and caudal vertebrae; cranio-caudal width of the atlas; orientation of the spinous process of the axis; length and cranio-caudal width of the spinous processes of the thoracic vertebrae; length of the spinous processes of the lumbar vertebrae; length and orientation of the transverse processes of the lumbar vertebrae; and the number of sacral vertebrae that articulate with the ilia. The ribs and vertebrae of the arboreal Ptilocercus lowii, the only ptilocercine, exhibit adaptations for a stable thorax that probably facilitate bridging locomotion. The vertebral columns of tupaiines, on the other hand, are more mobile and allow more flexion and extension of the spine; this increased flexion and extension increases stride length, which in turn increases speed in bounding or galloping mammals such as terrestrial tupaiines. It is proposed here that the attributes of the thorax of Ptilocercus are primitive for the Tupaiidae, that the ancestral tupaiid was arboreal, that the tupaiine condition is derived, and that the ancestral tupaiine was terrestrial. It is also proposed that: Ptilocercus may be primitive for the Archonta in its axial skeletal features; a stable thorax was first evolved in an arboreal ancestral archontan; the adaptations for stability of the thorax were retained in the Volitantia (dermopterans and chiropterans) for certain locomotor types, including gliding or flying; a mobile thorax evolved in conjunction with the shift to graspleaping in the ancestral euprimate. These scenarios may be further tested by quantitative analyses of vertebral osteology, as well as myological analyses of the epaxial musculature.

In spiders, cuticular scales are flattened, hollow setae that occur in a variety of shapes and colours. Using transmission electron microscopy and scanning electron microscopy, we examine and provide descriptions of the external and internal anatomy of prosomal and opisthosomal scales of 70 species of lynx spiders (Araneae, Oxyopidae), representing the genera Hamataliwa, Hostus, Oxyopes, Peucetia, Schaenicoscelis, Tapinillus, and Tapponia. The cuticular scales of these taxa exhibit regional (with respect to location on the body), sexual, inter- and intrageneric variation in external and internal morphology. In the genera, Peucetia, Schaenicoscelis, and Tapinillus, cuticular scales are plumose and only occur on the prosoma. Species of the genera Hamataliwa and Tapponia, have lanceolate scales that occur on the prosoma, legs, and opisthosoma. Hostus has spatulate scales in these areas. In the genus Oxyopes, most species have lanceolate scales on the prosoma and spatulate scales on the legs and opisthosoma. Examinations of the genitalia of 82 species of lynx spiders, revealed a strong correlation between genitalic morphology and scale shape and distribution.

Prezygotic reproductive isolation has traditionally been studied from a precopulatory perspective even though postcopulatory events have been known to influence success at fertilization. Postcopulatory, prezygotic reproductive isolation (gametic isolation) has received relatively little attention mainly because the focus of research has been on the events that occur either earlier (pre-mating) or later (postzygotic) in the chain of events that lead to successful reproduction. However, recent evidence from an array of taxa from sea urchins to beetles reveals that postejaculatory, prezygotic events may be an important factor in reproductive isolation. Such a mechanism may be the driving force behind speciation in some taxa, such as free-spawning marine invertebrates, whilst it may complement pre-mating and postzygotic mechanisms in others. In this paper we draw an analogy between sperm–egg interactions and classical sexual selection theory and argue that gametic incompatibility may arise through cryptic female choice.

The Namaqua rock mouse, Aethomys namaquensis (A. Smith, 1834), is a widely distributed species in southern Africa. Analysis of geographic variation among samples of A. namaquensis from southern Africa across a more comprehensive geographical coverage than has hitherto been considered for the species suggests the recognition of four subspecies: A. n. namaquensis (A. Smith, 1834); A. n. lehocla A. Smith, 1836; A. n. alborarius Peters, 1852; and A. n. monticularis Jameson, 1909, which differ both in cranial size and shape. The geographical limits of the proposed subspecies broadly coincide with major phytogeographical zones of southern Africa. This infraspecific taxonomic treatment of southern African A. namaquensis reduces the number of previously recognized subspecies or referred taxa from 16 to four. While the subspecies designations in this study are probably valid in terms of their constitution, their boundaries, however, require further refinement involving other systematic techniques, such as DNA analysis.