In chickens had teeth like a crocodile

Everybody knows that birds do not have teeth. But long ago, when dinosaurs roamed the Earth more, the birds had teeth. They have long lost their teeth, but a new study on the gene mutation talpid2 chickens showed that the genes for the growth of teeth they have left.

Biologist Matthew Harris of the Max Planck Institute in Tübingen, Germany, investigated the mutation of this gene. He was interested that affect the development of organs in chicken embryos. Harris made an accidental discovery, showed that the chickens could grow teeth, he saw the head of a 16-day chick embryo subjected to random mutation, and saw the tiny protrusions on the edge of the beak.



Scientists have long known about the lethal recessive gene talpid2, but never expected the relationship between the gene and the formation of teeth, because the mutant embryos do not survive until the egg - maturation period usually lasts for 21 days. However, the scientists were able to incubate them for up to 18 days and for the last day of the 18 they began to grow tiny teeth, which deprived the birds for several million years.

Teeth though they were small, but had a conical shape - this can be seen in the mouth of crocodiles or ancient fossilized birds. The earliest known ancestors of birds were called archosaurs - they had a mouth and teeth are very similar to crocodiles. The similarity is not surprising, since the birds are much more closely related to reptiles than mammals. Over time, the development of the beak has led to the birds lost their teeth and began to look like a modern, familiar to us the bird.



Surprisingly, the chicks mutants are still preserved the genes responsible for the formation of teeth, as the birds lost their teeth about 70-80-year-million years ago. Harris and his colleague John Fallon of the University of Wisconsin decided to continue their research and find out whether this gene is preserved in healthy chickens.

The activated gene talpid2 healthy chicken embryos also led to the formation of teeth in chickens - they got the same teeth "reptiles" and other similar genetic traits. The success of the experiment not only confirmed the hypothesis of the presence of teeth in ancient birds, but also proved that the formation of teeth in chickens mutants was not just a one-time random mutation.

via factroom.ru