The aim of this study was to identify the endophytic fungi of the medicinal plant Kigelia africana (Lam) Benth. (Bignoniaceae) and to investigate their potential antimicrobial activity. Seven species of endophytic fungi were successfully isolated from K. Africana for the first time: including Cladosporium sp., Aspergillus flavus, Aspergillus sp., Curvularia lunata as well as three unknown species. The fungal extracts were assessed for antibacterial activity against three standard pathogenic bacterial strains: Bacillus subtilis, Staphylococcus aureus and Escherichia coli. Most of the extracts showed in vitro inhibition of bacterial growth. The phytochemical screening revealed the existence of a diverse group of secondary metabolites in the crude extracts of the endophytic fungi that resemble those in the host plant extracts.

Within certain regions in East Africa, the butterfly Danaus chrysippus (L.) shows female‐biased population sex ratio, because of the production by some females of all‐female broods, as a result of infection by maternally inherited, male‐killing bacterium of the genus Spiroplasma. In this study, we describe a 3‐year field survey for the population dynamics of the male‐killing Spiroplasma in D. chrysippus in four independent localities, namely Uganda, Ghana, Sudan and Madagascar. The prevalence of the bacterium was found to show extensive variations at multiple scales among different sites, in various countries, seasons and years. A novel, selection‐based hypothesis was suggested to explain the high variability of male‐killer prevalence over space and time, based on the existence of an adaptive link between larval food‐plant density and the magnitude of resource reallocation fitness advantage for the male‐killer.

Within the region of East and Central Africa, the aposematic butterfly D. chrysippus is characterized by unusual ecology, due to the co-occurrence of polymorphism, mimicry and sex ratio distortion. In this paper, we describe a survey conducted for D. chrysippus at Khartoum, based upon morphological and molecular investigations. The goal of the study was to determine whether Sudan is a part of the presumed hybrid zone of D. chrysippus in Africa, where the butterfly shows the unusual ecology. D. chrysippus was found to display considerable colour pattern polymorphism. Only one mimetic form, the batesian mimic, female Hypolimnas misippus was recorded. The population sex ratio of D. chrysippus did not show significant deviation from the 1:1 ratio. Molecular tests for the male-killing bacteria Spiroplasma yielded negative results. The study concluded that central Sudan belongs to the hybrid zone but lacks its characteristic ecology.

The diversity of bird species is expected to vary with habitat type even at the smallest spatial scales. In this paper, we describe a preliminary survey conducted for the avifauna at two locations in Khartoum city, namely, Sunut forest and Tuti Island. The ecology of both sites is influenced by their proximity to the Nile River and thus they are characterized by dense vegetation cover. Moreover, the two sites lie very close to each other, implying that the climatic conditions are virtually identical. However, the two sites differ with respect to one major environmental respect, that is, the intensity of human influence. Tuti Island represents a man-made habitat and the vegetation at the site is mainly agricultural. On the other side, Sunut forest is a natural habitat and the vegetation cover at the site is dominated by the wild Acacia nilotica trees. The goal of the study is to compare the bird composition between the two sites in order to assess the effect of habitat type on the spatial variation in the abundance and diversity of birds. Overall, forty one species were recorded at the two sites during a five-month period: twenty four species at Sunut forest and thirty species at Tuti Island. Statistical investigation of avian diversity using Shannon index has detected a significant difference between the two sites, most likely due to variable human impact.

Sex ratio distortion in the tropical butterfly Acraea encedana is caused by infection with a male-killing bacterium of the genus Wolbachia. Previous research on this species has reported extreme female bias, high bacterial prevalences, and full sex role reversal. In this paper, we provide an assessment for the dynamics of the male-killer, based on a survey for sex ratios and Wolbachia prevalences among wild populations of A. encedana in Uganda. The study reveals that Wolbachia infection showed considerable variation over both spatial and temporal scales.