Savanna Regions Of Africa Research Articles

Eighty‐three lineages that took over the world: a first review of terrestrial cosmopolitan tetrapods

AbstractAimWhile there is a huge macroecological and biogeographical literature addressing endemism, very little has been done to systematically study lineages that are widely distributed across the globe. Our aim here was to list and analyse those lineages of terrestrial tetrapod vertebrates found in 60–90% of the world, loosely termed here as cosmopolitan.LocationGlobal.MethodsTwo sets of geographical units and three occupancy criteria were used to list, analyse and map cosmopolitan lineages and their sister lineages.ResultsAmong the 83 lineages identified, 2 were represented by amphibians, 9 by reptiles, 13 by mammals, and the remainder by birds, of which 12 were passerines and 47 were non‐passerines. All these lineages are present in parts of Southeast Asia, most of them throughout much of Eurasia and Africa, but fewer in South America and very few in Australia. Only three of the lineages (all reptiles) are likely to exemplify vicariance or early dispersal‐driven cosmopolitanism, the rest having attained world‐wide distribution via extensive, geologically recent dispersal. The distribution of sister lineages indicates that many cosmopolitan lineages probably originated in the savanna regions of Africa, some in Southeast Asia, and fewer in tropical America.Main conclusionsCosmopolitan distributions in tetrapods are primarily the result of dispersal, with large body size and the ability to fly being two key correlates of rapid global colonization. We argue that a cosmopolitan lineage framework in biogeographical and ecological studies could add great depth to the understanding of evolutionary success, and would be highly relevant to the field of invasion biology.

Smallholder farmers’ perceptions of and adaptations to climate change in the Nigerian savanna

The savanna region of Africa is a potential breadbasket of the continent but is severely affected by climate change. Understanding farmers’ perceptions of climate change and the types of adjustments they have made in their farming practices in response to these changes will offer some insights into necessary interventions to ensure a successful adaptation in the region. This paper explores how smallholder farmers in the Nigerian savanna perceive and adapt to climate change. It is based on a field survey carried out among 200 smallholder farm households selected from two agro-ecological zones. The results show that most of the farmers have noticed changes in climate and have consequently adjusted their farming practices to adapt. There are no large differences in the adaptation practices across the region, but farmers in Sudan savanna agro-ecological zone are more likely to adapt to changes in temperature than those in northern Guinea savanna. The main adaptation methods include varying planting dates, use of drought tolerant and early maturing varieties and tree planting. Some of the farmers are facing limitations in adapting because of lack of information on climate change and the suitable adaptation measures and lack of credit. The study then concludes that to ensure successful adaptation to climate change in the region, concerted efforts are needed to design and promote planned adaptation measures that fit into the local context and also to educate farmers on climate change and appropriate adaptation measures.

Environmental adaptations of the African snailLimicolaria festiva Martens

L. festiva is able to exist in the hot, arid, Sahel savanna regions of Africa in consequence of its nocturnal circadian rhythm of locomotory activity, and its low rate of water loss during periods of inactivity when an epiphragm has been secreted and while the snail is aestivating.