Neogene desertification of Africa - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Comptes rendus - Géoscience Année : 2009

Neogene desertification of Africa

Résumé

Throughout the Neogene, the faunas and floras in Africa recorded global climatic changes. We present an overview of Neogene desertification in Africa by tracing stable isotopes in eggshells and mammalian enamel, by faunal (changes in hypsodonty, etc.) and floral changes in sequences at the latitudinal extremities of the continent and the equator. This work reveals that desertification started in the southwest ca 17-16 Ma, much earlier than the region of the present-day Sahara (ca 8-7 Ma) and long before the deserts in East Africa (Plio-Pleistocene). A consequence of this history is that animals and plants inhabiting the South of the continent had a long period of time in which to adapt to arid, unstable climatic conditions. When parts of East Africa became arid during the Late Miocene and Plio-Pleistocene, several of these lineages expanded northwards and occupied developing arid niches before local lineages could adapt. Several of the latter became extinct, while others withdrew westwards as the tropical forest diminished in extent. It is proposed that the history of desertification in Africa was related to that of the polar ice caps (Antarctic, Arctic).

Dates et versions

hal-04114995 , version 1 (02-06-2023)

Identifiants

Citer

Brigitte Senut, Martin Pickford, Loïc Ségalen. Neogene desertification of Africa. Comptes rendus - Géoscience, 2009, 341, pp.591-602. ⟨10.1016/j.crte.2009.03.008⟩. ⟨hal-04114995⟩
5 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More