Create modern chickens with dinosaur legs for evolutionary research

By inhibiting the expression of a gene in modern chickens, scientists created a pair of legs-like chickens with its ancestral dinosaurs. Although the study only stopped at the level of embryos instead of studying and hatching eggs and maturing chickens to show us, this is an important finding, providing more insight into the evolutionary process. from dinosaurs that survived the disaster 65 million years ago into modern birds today.

Until recently, the dinosaur extinction 65 million years ago is still one of the greatest mysteries of science. But thanks to some recently discovered fossils about avian dinosaurs, we have learned that some dinosaurs are extinct after the meteorite and Earth collision, others Still alive and evolving into birds living with us right away.

On some bird-like dinosaurs, such as Archeopteryx , the fibula is a long, tubular bone down to the ankles. Besides the bone, it also has a tibia with the same length. However, according to what scientists know, during evolution from a group of bird-like dinosaurs into Pygostylians, this spine becomes shorter than the tibia, gradually thinning, blunt and no longer pulling. Long to fish.

Until recently, the dinosaur extinction 65 million years ago is still one of the greatest mysteries of science.

Although at the stage of modern embryonic development, there are still signs of a dinosaur-shaped bone like a dinosaur, but when it grows, the bone gradually shrinks, is thinner and withdraws to the pillow similar to Pygostylian species. In order to find out how this evolution took place, Chilean scientists refined the genome of a normal chicken so that their legs formed a dinosaur-like bone.

To do this, they inhibited the expression of an Indian Hedgehog (IHH) gene, which helps the tubular bone of the embryo continue to grow normally, extending down to the fish. As a result, they discovered some pretty strange points. Normally in the development of bone, the cells divide and stop in the middle of the bone before a head stops growing. But in modern chickens, this development begins to stop right from the head of the bone.

This means that the chicken bone section is blocked so that it does not extend down to the fish as its ancestors. Researchers believe that in the early stages of maturation of the head of the modern chicken leg is motivated by a bone under the fish called the heel bone (spleen): "Different from other animals , the heel bone of the embryo is pressed towards the lower end of the fibula ".

At the same time, the group thinks that in normal chickens, the interaction between the heel bone and the head of the fibula has been prevented by the same signal as preventing bone growth in the axis, making it impossible to reach the ankle. . However, when they turned off the IHH gene, the heel bone strongly activated the activity of a PthrP protein , allowing the bone to grow. The end result is that the chicken has a protruding tubular bone that touches the fish similar to its ancestor, Archeopteryx.

Unfortunately, the dinosaur hybrid chicken is only created and studied by scientists in the infancy, not hatching to mature. However, the determination of biological processes that led to evolution from dinosaur feet and chicken feet is a great discovery, helping scientists better understand the evolutionary history of a relatively dark period. toothpick " in science.