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Habitat heterogeneity is a key driver of the diversity and distribution of species. African savannas are experiencing changes in their vegetation structure causing shifts towards increased woody plant cover, which results in vegetation structure homogenization. Given the impact that increasing woody plant cover has on patterns of animal use, resource managers across Africa are implementing habitat management practices that are intended to reduce woody plant cover. To understand the ecological implications of various habitat management practices on arthropod and bird communities, we leveraged large‐scale tree clearing and subsequent mowing in an African savanna to understand how changes in both the herbaceous layer and woody plant cover (i.e., structural heterogeneity) may shape arthropod and bird communities at the local scale. We focused on four replicated treatments: (1) annual summer mow, (2) annual winter mow, (3) >5 years since last mow (rest), and (4) an adjacent unmanipulated savanna to act as a control. We found that the mowing treatments significantly influenced vegetation structure both with respect to tree density and herbaceous layer. Both arthropod and bird community composition varied across treatments. Grass biomass was the best predictor of arthropod richness and abundance, with arthropods selecting for areas with high biomass. Insectivorous bird richness and abundance was driven by tree density (i.e., perching locations) and not arthropod abundance. Our results suggest that vegetation management practices contribute to habitat heterogeneity at the landscape scale and increase bird species richness through species turnover. However, we caution that if a single vegetation management practice dominates the landscape, it is plausible that it could lead to the simplification of the avian community. [ABSTRACT FROM AUTHOR]

The Sydney Declaration (SD) has the inherent virtue of shifting the focus from the tools used in forensic science to the fundamental characteristics of appropriate forensic practice analysis of a situation and all related trace data for the purpose of resolving a case. Though several differences might be observed between countries regarding the technologies used, the fundamental principle of forensic logical reasoning are universally applicable to all contexts and environments and not only restricted to sophisticated, well-resourced, established forensic science laboratories based in countries that offer adequate resources, strong networks and legal frameworks. In Africa, several countries lack resources to train practitioners and to develop forensic science institutes, laboratories and other relevant institutions. The SD can serve as departure point to attain appropriate forensic science outcomes. Upholding its sound guidance can help forensic science practitioners remain faithful to their science, acknowledge their limits, give expert opinions based solely on facts and scientific analysis and interpretation, whilst also enhancing communication with their stakeholders. As forensic science develops in Africa, the SD presents a timely opportunity for us to proceed with a common understanding and a solid foundation through which our field can grow. [ABSTRACT FROM AUTHOR]

Keywords: forensic science; forensic science laboratory; research integrity; Africa; bias; oversight; networks; mentoring EN forensic science forensic science laboratory research integrity Africa; bias oversight networks mentoring 295 302 8 02/01/22 20211201 NES 211201 I If the law has made you a witness, remain a man [practitioner i [1] I ] of science. Missing one of these key mechanisms in a national forensic science ecosystem will undermine the value that forensic science may offer to the justice system. Networks, mentoring, research integrity, forensic science, forensic science laboratory, Africa; bias, oversight. [Extracted from the article]

Presents a study which examined the variation of 77 biallelic sites located in the nonrecombining portion of Y chromosome in a sample of male from African populations. Subjects and methods; Results; Discussion.

Examines the genetic affinities of biallelic and microsatellite of Y chromosome polymorphism among African populations. Combination of dinucleotide-repeat polymorphism in establishing Y chromosome compound superhaplotypes; Distribution of microsatellites within haplotype; Diversity of Y chromosomal biallelic haplotypes.

Human mtDNA shows striking regional variation, traditionally attributed to genetic drift. However, it is not easy to account for the fact that only two mtDNA lineages (M and N) left Africa to colonize Eurasia and that lineages A, C, D, and G show a 5-fold enrichment from central Asia to Siberia. As an alternative to drift, natural selection might have enriched for certain mtDNA lineages as people migrated north into colder climates. To test this hypothesis we analyzed 104 complete mtDNA sequences from all global regions and lineages. African mtDNA variation did not significantly deviate from the standard neutral model, but European, Asian, and Siberian plus Native American variations did. Analysis of amino acid substitution mutations (nonsynonymous, Ka) versus neutral mutations (synonymous, Ks) (kaks) for all 13 mtDNA protein-coding genes revealed that the ATP6 gene had the highest amino acid sequence variation of any human mtDNA gene, even though ATP6 is one of the more conserved mtDNA proteins. Comparison of the kaks ratios for each mtDNA gene from the tropical, temperate, and arctic zones revealed that ATP6 was highly variable in the mtDNAs from the arctic zone, cytochrome b was particularly variable in the temperate zone, and cytochrome oxidase I was notably more variable in the tropics. Moreover, multiple amino acid changes found in ATP6, cytochrome b, and cytochrome oxidase I appeared to be functionally significant. From these analyses we conclude that selection may have played a role in shaping human regional mtDNA variation and that one of the selective influences was climate.