The shocking discovery of snakes and evolution of the human eye

A new study published in the journal Proceedings of the National Academy of Sciences shows that our ancestors have developed the ability to observe sensitivity of the eye in part because . the fear of species snake.

New research conducted by neuroscientist Hisao Nishijo and Le Van Quan at Toyama University (Japan) shows that in the brain of Indian short-tailed monkeys, neurons are particularly reactive to images. of snakes.

Nishijo's lab studied neurological mechanisms responsible for this monkey's emotions and fears.Reaction to snakes is an instinctive reaction that occurs without learning or remembering. The participating monkeys were raised in a walled area and had never seen snakes.

Picture 1 of The shocking discovery of snakes and evolution of the human eye
The human eye develops because the ancestors are afraid of snakes.(Photo: Scienceagogo)

"The number of neurons is more sensitive to snakes and responds more quickly and aggressively than other neurons, " Nishijo said. "Monkey brains have special neural circuits to detect snakes and they have been encoded in genetic genes."

The hypothesis was first published by Lynne Isbell, a professor of anthropology at the University of California, Davis: 'Fruit, Tree and Snake' (The Fruit, the Tree, and the Serpent) in 2006. She said that our ancestors - primates - have developed the ability to observe closely at close range mainly to detect and stay away from dangerous snakes.

The book explains, today's mammals and snakes are big enough to eat them to grow at about the same time - 100 million years ago. Scientists say poisonous snakes appeared about 60 million years ago and shared living space with primates.

Commenting on the findings of Nishijo, Isbell said, she was surprised when neurons were more sensitive to snakes than the number of facial sensitive neurons (helping primates to be animals with High sociality).

"We are looking for explanations that are consistent with the idea that snakes have affected the natural selection process of primates , " she added. "I don't see any reason to explain the sensitivity of nerve cells to snakes, except through the evolutionary path."