IUCN / SSC Cat Specialist Group - Digital Cat Library
   

 

View printer friendly
Fernandes, C.A.; Rohling, E.J.; Siddall, M.
Absence of post-Miocene Red Sea land bridges: biogeographic implications
2006  Journal of Biogeography (33): 961-966

In a large number of studies concerned with species movements between Africa and Eurasia, including the migrations of hominids out of Africa, a frequently cited dispersal route is across a hypothetical land bridge in the southern Red Sea, which is suggested to have emerged during glacial sea-level lowstands. This paper, however, unequivocally demonstrates that palaeoceanographic and palaeoecological data are incompatible with the existence of Red Sea land bridges since the Miocene. The case is made by presenting the first quantitative history of water depth above the Red Sea sill for the last 470,000 years, a time period that includes the four most recent glacial-interglacial cycles, and by discussing the predictable consequences of any land bridge formation on the Red Sea sedimentary and microfossil records. The absence of post-Miocene Red Sea land bridges has extensive implications for biogeographic models in the Afro-Arabian region. Genetic, morphometric and palaeontological patterns reported in the literature cannot be related to dispersals over a land bridge, or in the case of marine organisms, separation of the Red Sea from the Indian Ocean by a land bridge. If such patterns in terrestrial species are only congruent with a southern Red Sea dispersal route, then they need to be considered in terms of sweepstake rafting, anthropogenic introduction, or in the particular case of the Out-of-Africa migration by modern humans, seafaring. The constraints imposed by our palaeoenvironmental record on biogeographic reconstructions within and around the Red Sea will hopefully encourage both the review of previous works and the preference for multidisciplinary approaches in future studies.

PDF files are only accessible to Friends of the Cat Group. Joining Friends of the Cat Group gives you unlimited access and downloads in the Cat SG Library for one year, and allows you to receive our newsletter Cat News (2 regular issues per year plus special issues). More information how to join here

 

(c) IUCN/SSC Cat Specialist Group ( IUCN - The World Conservation Union)