Did Human Ancestors Incite By Ancient Supernovas For Walking Upright?

An article published today in the Journal of Geology explains: supernovas bombarded Earth with cosmic energy beginning about 8 million years ago, with a peak 2.6 million years ago, initiating an avalanche of electrons in the lower atmosphere and activating a chain of events that possibly ended with bipedal hominids like Homo habilis, nicknamed "skillful man".

The authors believe that atmospheric ionization probably caused a huge increase in cloud-to-ground discharges that caused forest fires around the world. These infernos could be one of the reasons why the ancestors of Homo sapiens developed bipedalism: to adapt to the savannahs that replaced burnt forests in northeastern Africa.

"It is thought that there was already a tendency for hominids to walk with two legs, even before this event," said lead author Adrian Melott, professor emeritus of physics and astronomy at the University of Kansas. "But they adapted mainly to climb the trees, and after this conversion to the savannah, they would have to walk much more often from one tree to another through the pastures, so they become better at walking upright. It is believed that this conversion to savannah contributed to bipedalism as it became more and more dominant in human ancestors. "

Based on a "revealing" layer of iron-60 deposits that line the seabed of the world, astronomers have exploited high-confidence supernovae in the immediate cosmic neighborhood of the Earth: between 100 and only 50 parsecs (163 light years ) away, during the transition from the Pliocene epoch to the ice age.

"We calculate the ionization of the atmosphere from cosmic rays that would come from a supernova as far as the iron-60 deposits indicate," said Melott. "It seems that this was the closest in a much longer series, we maintain that it would increase the ionization of the lower atmosphere by 50. In general, the ionization of the lower atmosphere is not obtained because the cosmic rays do not penetrate that. , but the most energetic of the supernovas reach the surface, so many electrons will be removed from the atmosphere. "

According to Melott and co-author Brian Thomas of Washburn University, ionization in the lower atmosphere meant that the abundance of electrons would form more pathways for lightning.

"The bottom mile of the atmosphere is affected in a way that normally never does," Melott said. "When high-energy cosmic rays hit atoms and molecules in the atmosphere, they eliminate electrons, so these electrons are loose instead of being attached to atoms." Generally, in the process of lightning, there is an accumulation of voltage between the clouds, or the clouds and the ground, but the current cannot flow because there are not enough electrons to carry it in. Therefore, it has to accumulate high voltage before the electrons start to move in. Once they move, the electrons eliminate more electrons, more atoms, and it becomes a ray, but with this ionization, that process can start much more easily, so there would be many more rays. "

By: Preeti Narula

Content: https://www.sciencedaily.com/releases/2019/05/190528095301.htm