Summary: | Rodent communities and populations in the Sudanian savanna of Eastern Senegal were investigated in relation to the intensity of human-made changes of the environment. One of main drivers of the global change, land use, caused significantly higher abundances of rodent communities in agriculture landscape via to increasing dominancy of the ubiquitous murid species Mastomys erythroleucus, than was observed for pristine savannas inside the Niokolo Koba National Park. At population level, the fragmentation and deforestation of wooded savanna, potentially facilitated by climatic changes in this sub-Saharan region, indicated significant changes in genetic diversity of another species, the partly arboreal Praomys daltoni. Microsatellite allelic richness and expected heterozygosity were significantly lower, and population differentiation higher in isolated populations in the northern limit of its distribution area, where they have left deforested landscape and survive only in villages, than in southern localities with continuous P. daltoni distribution. Another main aspect of the global environmental change is the human-mediated introduction and spread of the invasive black rat Rattus rattus, whose colonization of Senegal was described using recently developed Bayesian approach based on microsatellite data. The most likely evolutionary scenario indicated multiple introductions and several subsequent admixture events, which might support its invasion success. Substantial consequences of human impact on rodents were found at both community and population levels, implying important effects on biodiversity and human well-being Les rongeurs de la savane soudanienne du Sénégal-Oriental ont été examinés en relation avec l'intensité des changements liés à l'homme. Un des moteurs principaux du changement global, l'usage des terres, a causé une augmentation significative des abondances de rongeurs dans les milieux cultivés par rapport aux savanes naturelles du Parc National du Niokolo-Koba. Ceci est du surtout à l'augmentation ...
|