For about half a billion years, our predecessors had tails growing from their bodies. They swam across the Cambrian seas using the tails of their prehistoric ancestors. It wasn’t until much later, when they developed into primates, that their tails proved invaluable in keeping them balanced as they raced from branch to branch through Eocene rainforests. However, about 25 million years ago, the tails of the dinosaurs vanished.
Our old anatomy had undergone a transformation, which was first seen by Charles Darwin. However, the specifics of how and why it occurred remain a mystery.
Now, according to a team of experts in New York, they have identified the genetic mutation that may have resulted in the loss of human tails. When the scientists performed this genetic modification in mice, the animals did not develop tails, according to a recent research that was published online only last week.
This major anatomical shift has a significant effect on the course of human development. It is thought that the tail muscles of our forefathers developed into a hammock-like net over the pelvis. Few million years ago, when the ancestors of humans rose up and began walking on two legs, that muscular hammock was ready to sustain the weight of their organs in their upright position.
Although it is difficult to establish beyond a reasonable doubt that this mutation resulted in the lopping off of our ancestors’ tails, “it is as near to a smoking gun as one could wish for,” said Cedric Feschotte, a geneticist at Cornell University who was not involved in the research.
Charles Darwin startled his Victorian listeners when he claimed that humans evolved from monkeys with tails. The coccyx, which is a small collection of vertebrae that extends beyond the pelvis, is shared by humans and apes, he pointed out, despite the fact that humans and apes don’t have a visible tail.
Throughout the years, paleoanthropologists have discovered fossils that have given some insight on the process of metamorphosis. Most surviving primates, such as lemurs and nearly all monkeys, still retain tails, despite the fact that they are extinct. However, when apes first emerged in the fossil record about 20 million years ago, they did not possess a tail at all.