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Dwarf geckos, , are small, secondarily diurnal lizards that occur in Africa, South America and Madagascar. Identification of many species is based on scale features only, and is therefore extremely difficult in the field due to their small size. Based on DNA sequences of a fragment of the mitochondrial 16S rRNA gene we studied the relationships among the Malagasy taxa and their differentiation relative to some African . The results do not contradict a division of Malagasy into three main lineages, which had been defined as Oriental, Occidental and Meridional clades. However, while the Oriental lineage (subgenus ) was very strongly corroborated by our analysis, no significant support was found for the other groupings. No evidence for a monophyletic group of the Malagasy taxa, or for a monophyletic to the exclusion of was found. The genetic divergences among Malagasy were surprisingly large, indicating a relatively old age of most species and especially of the major lineages.

In live specimens of the dwarf gecko from different localities in Tanzania, Malawi, Zambia, Namibia and South Africa, scalation patterns and colouration of adults and hatchlings were investigated. All specimens examined share the same scalation pattern, but they differ in the number of preanal pores in males. Males from southern Africa generally possess 4 to 5 preanal pores, whereas those from Tanzania possess 7 preanal pores. The general colouration of specimens from southern Africa is brown with a camouflaging pattern of streaks and dots. The extent of the streaks and the number of the spots are quite variable between specimens from different localities and - to a lower extent - between specimens of the same population. Additionally, the colouration strongly depends on internal factors as well as external stimuli, e.g. disturbance. While all specimens from southern Africa share this basic colouration, the Tanzanian specimens are usually coloured grey and possess conspicuous whitish spots with black edges. Their ability to change colour is limited. Hatchlings of all forms except those from Tanzania are again quite similar, with a brownish body and a bright orange-red tail. In contrast, hatchlings of the Tanzanian specimens are dark brown during their first days and become grey subsequently. Additionally, only the undersides of their tails are reddish. The Tanzanian form stands apart from the other populations of as far as colouration and some morphometric data are concerned. Due to unsatisfactory definitions of East African species, it is not yet clear whether the Tanzanian form is referable to . [] . Alternatively, it may be a member of the complex.

Knowledge gaps for birds migrating within Africa, or visiting the continent either for breeding or wintering, have been identified systematically by datamining the Global Register of Migratory Species (GROMS). The Register contains a migratory vertebrate species reference list, GIS maps and a literature database with full-text passages on migration. Using the GROMS literature and accessory tables for data mining, knowledge gaps with respect to migration routes and seasonal timing were diagnosed for more than 150 bird species. This analysis was based on a search for text strings such as “migration unknown”, “poorly known”, “surprisingly little known”, etc. The species list of lesser-known migrants generated by data-mining has been published on the GROMS website (www.groms.de), and provides a starting point for future research. The underlying complex query uses Standard Query Language (SQL), requiring a fully documented relational database. Such documentation is often lacking for current biodiversity information systems, which limits their use for complex data mining.

Madagascar’s lowland littoral forests are rich in endemic taxa and considered to be seriously threatened by deforestation and habitat fragmentation. In this study I examined how littoral forest bird communities have been affected by fragmentation at the landscape scale. Bird species composition within 30 littoral forest remnants of differing size and isolation was determined using point counts conducted in October — December in 2001 and 2002. Each remnant was characterised by measures of remnant area, remnant shape, and isolation. Step-wise regression, nestedness analysis, and binomial logistic regression modelling was used to test the relationship between bird species and landscape variables. Bird species richness in remnants was significantly (p<0.01) explained by remnant area but not by any measure of isolation or landscape complexity. The bird communities in the littoral forests were significantly (p<0.01) nested. The majority of forest-dependent species had significant (p<0.01) relationships with remnant area. As deforestation and fragmentation are still significant issues in Madagascar, I recommend that large (>200 ha) blocks of littoral forest are awarded protected status to preserve what remains of their unique bird community.

This study is using new technologies such as satellite telemetry and remote sensing data to identify important habitats of migratory birds (). Previously collected telemetry data are being used for further analysis to localise regions of frequent stopovers during migration and wintering. An index has been developed to calculate migration and staging periods semi-automatically from the satellite dataset. African land cover maps were used to characterise these staging sites. First results show the importance of wintering sites in Chad and Sudan, where the preferred habitats consist of savanna, grassland and cropland.

This paper highlights representatives of the bird family Platysteiridae in the DR Congo which merit special conservation attention because of the following distinctive characteristics: (1) morphology (plumage coloration) that is unusual within family: sexual monomorphism or polymorphism in the male; (2) ecological specialisations: restricted to the forest canopy; occurring near the forest floor; restricted to the submontane zone; or restricted to a single vegetation type.

These species occur mainly outside nature reserves, and thus urgently require additional protection. The morphological diversity of in DR Congo is also discussed and a colonisation history of its southern population is suggested.

Two central African forest weavers, and , are known only from < 10 specimens each since 1920, and < 3 sightings each in the past 40 years. A re-examination of the available data raised the possibility that these taxa might be hybrids. For , the postulated parental species are X . For , the parental species could be X , but it seems more likely that represents an unrecognised plumage stage of . Resolution of the status of these two species is relevant to assessments of biodiversity, and conservation priorities, in the Ituri region.

Local mammalian communities in Africa present the highest species richness in the world, only paralleled by some communities in the Oriental biogeographic region. Differences in mammalian species richness are especially outstanding when compared with South American communities, despite their similar latitudinal position and regional species richness. Recent study has shown that these differences are not only related to contemporary determinants but also to biogeographic-historic factors, which acted on the composition of the regional pool of species. One of the main differences in composition between the two regions relates to the high diversification of large mammals in Africa, which greatly contributes to the high values of local community richness in this region. The absence of extant large mammals in the South American region has been proposed to result from Pleistocene-Holocene extinctions, which affected large mammals all over the world. However, a gradual pattern of decrease in the abundance of large mammal species can be appreciated in almost all regions except Africa since the late Miocene and through the Pliocene. To test these hypotheses we compare the patterns of macromammal body mass distribution — at regional and local scales — in the two regions over the past 20 million years and relate the observed changes to major geological events.

We used line transect counts to collect data on population abundance of primates and small antelopes from three different moist forest blocks within the Udzungwa Mountains of south-central Tanzania. Results show that both diversity and relative abundance (number of primate groups/individual antelopes seen per km walked) are generally higher in the lower part (300–800 m a.s.l.) of Mwanihana Forest (Udzungwa Mountains National Park), than in medium to high altitude and less protected forests (Ndundulu Forest, 1400– 2100 m a.s.l., and New Dabaga/Ulangambi Forest Reserve, 1800–2100 m a.s.l.). The latter, in particular, is the most degraded and encroached forest patch, and presents the most impoverished community. The combined effects of altitude, hunting and human-induced alteration of forest cover might account for the differences observed.

As part of an interdisciplinary project on biodiversity (BIOTA South), basic data on small mammal diversity and reproduction from three sampling periods along a transect covering a rainfall gradient in Namibia are presented. A total of 16 species (350 specimens) of Soricidae, Rodentia, and Macroscelidea were captured. Small mammal diversity was highest in the farming area north of Windhoek, whereas it was low in an overgrazed site in the drier south. Reproductive data supports seasonality of reproduction after the rainfall in the north of Namibia but not in the southern sites.