The truth about the sixth sense of humanity

The common ancestor of humans and sharks as well as many other vertebrates and jaw on Earth used to be a sixth sensory organism with the ability to detect underwater electric fields.

Tools to support this ability, called electroreceptors and electrosensory, appear from the same cell population in the Chondrichthyes class cartilage (like sharks). , stingray) or vertebrate fish (such as sturgeon or spotted sturgeon) along with some salamanders, according to the conclusion published in Development magazine. People have unfortunately lost this sixth sense from a long time ago.

Position electrosensory cells of a stingray in the embryonic stage
Pregnancy is marked with black spots. (Photo: Andrew Gillis)

The leader, author Andrew Gillis, a biologist at Dalhousie University, said: 'Nowadays on human embryos, there are no structures that contribute to the formation and development of an ancestral receptor. we too . So, humans have lost their ability to detect underwater electric fields. "

The team made that remark after using long-term cell tracking techniques to study 70-day-old stingrays. The investigation revealed that the fish's electrosensory system is substantially more complex than ancestral organisms.

'The last common ancestor of a vertebrate group and jawbone is a live fish about 450 million years ago , ' Gillis said. Electrosensory allows them to easily hunt underwater. Accordingly, when prey hovering in front of or moving through the gills, they will create changes in the surrounding electric field to help see better. As they began to move ashore, their evolution was due to various hunting activities, so the natural ability to detect underwater electric fields was also lost over time.

However, today, some mammal species such as dolphins or platypus species that live near water retain this ability thanks to changes in the nervous system after toxic evolution. up. Many other species, such as South American electric fish, Torpedo-finned fish, are often used in stunning prey or against enemies, even in communicating or choosing partners.

Reference: Discovery