The first people are not responsible for the historic extinctions of megaherbivores in Africa, according to a study

According to a new study, early humans are not responsible for the extinction of large mammals in Africa many millions of years ago.

Tyler Faith, Curator of Archeology at the Utah Museum of Natural History, and his team challenged the long-held belief that early humans contributed to the disappearance of megaherbivores through hunting. Instead, changes in the environment have actually caused the death of these animals.

Do not blame human ancestors

There were a large number of megaherbivores – phytopharmaceutical animals weighing about 2,000 pounds – in Africa. At present, there are only five, namely the hippopotamus, giraffe, elephant, white rhino and black rhinoceros.

Some scientists have always attributed the disappearance of these animals to the evolution of hominids carrying tools and meat eaters. Apparently, this is not the case.

The study published in the journal Science reviewed the record of 7 million years of extinctions of herbivores in East Africa. The researchers found that about 4.6 million years ago, the diversity of megaherbivores had steadily declined on the continent and that it had begun long before human ancestors began to slaughter animals. In fact, the decline began well before the appearance of any species of hominin capable of hunting large mammals.

Environmental factors

The team of researchers also examined independent recordings of environmental and climatic trends over the last 7 million years, particularly global recordings of atmospheric CO2 and stable carbon isotopes of vegetation structures. .

The analysis revealed that 28 megaherbivore lines had disappeared. This coincided with the expansion of grasslands, which resulted in a drop in atmospheric CO2 over the last 5 million years.

"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 scientist at the University of Massachusetts Amherst. "We know that many of the missing megaherbivores are feeding on woody vegetation, so they seem to be disappearing along with their food source."

In addition, the loss of megaherbivores millions of years ago could also have caused the extinction of other animals. African carnivores who thrived on eating juvenile elephant meat, for example, could have extinguished due to the disappearance of their main prey.

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