In this archival photo, a herd of adults and baby elephants walks at dawn. Mount Kilimanjaro, Tanzania, is in the background, in Amboseli National Park, in southern Kenya. Elephants are one of the few megaherbivores that still exist.(Photo: Ben Curtis, AP)

A new study disagrees with a long-held view that humans have eliminated large animals that once occupied Africa.

In the research published in the journal Science Friday, the authors analyzed data on megaherbivorous communities in East Africa over seven million years. A megaherbivore is a mammal weighing more than 2,000 pounds. They concluded that extinctions of various mammal communities in Africa had occurred before hunting evidence appeared.

The researchers wrote that the decline of animals would rather have been caused by environmental factors such as the decrease of atmospheric carbon dioxide and the expansion of grasslands.

"Low levels of CO2 favor tropical grasses over trees, and as a result, savannas have become less woody and more open over time," said John Rowan, a postdoctoral researcher at the University of Massachusetts Amherst. , involved in research. "We know that many of the missing megaherbivores are feeding on woody vegetation, so they seem to be disappearing along with their food source."

According to the analysis, the main author, Tyler Faith, an assistant professor in the Department of Anthropology at the University of Utah, reportedly disappeared from 28 megaherbivore lineages, beginning there is about 4.6 million years old. Today, there are only elephants, hippopotamuses, giraffes and white and black rhinos.

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Researchers at Oxford University in the UK warned researchers that it was unclear when humans began to reach large animal populations, but it is quite clear obvious that the human impact played a role in the losses, there are tens of thousands of years.

"The causes of the decline of megaherbivores are probably complex, multidimensional and variable in time and space," wrote René Bobe and Susana Carvalho in the same issue of Science.

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