Evolutionary study explains decline of African megaherbivores

A study conducted by the National Museum of Natural Sciences, the National Center for Research on Human Evolution, and the University of Alcalá provides new insights into the decline of African megaherbivores. Published in Nature Communications, the research suggests that the loss of diversity among animals weighing over one ton, such as elephants and hippopotamuses, was driven by exceptionally low speciation rates rather than increased vulnerability to extinction.

By analyzing 3,327 fossil records from 396 species over the last 23 million years, researchers reconstructed the evolutionary dynamics of herbivores including antelopes and giraffes. The findings indicate that as Africa became increasingly arid approximately 7.2 million years ago, landscape and vegetation changes reconfigured ungulate communities. While species turnover was initially high, the rate of new species appearing slowed significantly about 3.6 million years ago, even as extinction rates continued to rise through the beginning of the Pleistocene.