Tyrant dinosaurs are brothers with chickens

Tiny pieces of protein taken from a 68 million-year-old dinosaur bone have provided the first genetic evidence that suggests that the tyrant dinosaurs are distant relatives of chickens today.

"This is the first molecular evidence that shows the link between birds and dinosaurs," said Dr. John Asara, a Harvard Medical School student.

Many scientists have speculated that birds evolved from dinosaurs, based on a study of the bones of these ancient reptiles. However, until recently, no soft tissue was available to confirm that hypothesis.

(Photo: smh.com.au) Things changed in 2005, when assistant professor Mary Higby Schweitzer from North Carolina State University reported finding soft tissue, including blood vessels and cells, in one The piece of the tyrant dinosaur bone found in the sandstone class in Montana.

To serve his research, Asara used a highly sensitive mass spectrometry technique to determine the chemical composition of bone fragments provided by Schweitzer's team. First, he cleans out bone fragments, then splits it into peptide fragments (small parts of the protein), and then isolates it into amino acid sequences.

Asara has acquired seven distinct amino acid sequences, five of which are a special type of collagen - a fibrous protein found in bone. Next, he translated this sequence, and compared the collagen data of the living animals. Most of them are compatible with chicken collagen, while others are compatible with newts and frogs' collagen.

"Based on all the genetic information we have today, it can be seen that these sequences are closer to birds or chickens," Asara said.

Finally, the scientists hope to find the gene characteristic of the tyrant dinosaur, but this is not possible with such a small amount of samples.

Schweitzer, in another study, found that bone fragments of tyrant dinosaurs responded to antibodies in chicken collagen. This confirms the presence of bird-like proteins in dinosaur bones.

T. An