Could evolution bring dinosaurs back?


Did you see the box office success of the 1993 movie "Jurbadic Park" and you wondered "could it really happen? Could the dinosaurs come back?" The idea that these powerful creatures could roam the Earth again someday is for most human beings fascinating and terrifying in equal measure.

Even real-life scientists are intrigued as to whether the evolutionary process could lead us to the time of the tyrannosaurs. But Susie Maidment, a vertebrate paleontologist at the Natural History Museum in London, quickly dismissed the idea that A mosquito full of DNA preserved in amber for millions of years, as in the "Jurbadic Park", could help recreate an extinct dinosaur.

"We have mosquitoes and flies that bite since the time of the dinosaurs, and they are preserved in amber," Maidment said in a statement. "But when amber preserves things, it tends to preserve the shell, not the soft tissues, so blood is not preserved inside mosquitoes in amber." [Is It Possible to Clone a Dinosaur?]

Researchers have found blood vessels and collagen in dinosaur fossils, but these components do not have real dinosaur DNA in them. Unlike collagen or other robust proteins, DNA is very fragile and sensitive to the effects of sunlight and water. The oldest DNA in the fossil record is about 1 million years old, and the dinosaurs became extinct some 66 million years ago.

Maidment added: "Although we have what appears to be mosquito blood up to 50 million years old, we have not found DNA, and to reconstruct something, we need DNA."

Jamal Nasir, a geneticist at the University of Northampton in the United Kingdom, said he would not rule out the idea of ​​dinosaurs evolving from the dead. In his opinion, evolution is not fixed or planned. In other words, anything could happen. "Evolution is largely stochastic. [randomly determined], and evolution does not necessarily have to go in a forward direction; It could have multiple addresses. I would say that going back to the dinosaurs is more likely to happen the other way around, because the building blocks are already there. "

Of course, Nasir pointed out, there would have to be adequate conditions for the dinosaurs to reappear. "Clearly, one could imagine viral pandemics that could disrupt our genomes, our physiology and behavior beyond our control," he told Live Science. This, in turn, could create the right conditions for evolution to take a path towards the reinvention of ancient reptiles.

However, although evolution may not be directional in a particular sense, something we do know is that we do not see the same animal evolve again, countered Maidment. "We can see an animal that is closely related and occupies a similar ecological niche, for example, ichthyosaurs were marine reptiles with long pointed snouts and dolphin-like shapes and tails," he told Live Science. "Today we see the dolphin, and probably occupy a similar ecological niche, but we would not describe a dolphin as an ichthyosaurus because they do not have the anatomical characteristics that allow them to be ichthyosaurs." [What If a Giant Asteroid Had Not Wiped Out the Dinosaurs?]

In addition, the dinosaurs never completely died out, said Maidment. The birds evolved from dinosaurs that ate meat, and therefore, in strict biological definition, all that evolved from this common ancestor is a dinosaur, which shares the same anatomical characteristics, he said.

"The dinosaurs are still with us," said Maidment. "They say dinosaurs are extinct, but only non-avian dinosaurs are extinct, birds are dinosaurs and birds are evolving, so we will certainly see new species of birds evolving, and these will be new species of dinosaurs."

Some scientists are even dabbling in the process of evolution when trying to reverse engineer a chicken to turn it into a dinosaur, called "chicken-dinosaur". However, this beast, if it ever comes to fruition, would not be a replica of a dinosaur, but a modified chicken, said Jack Horner, a research badociate at the Burke Museum at the University of Washington, according to Live Science.

Things have changed drastically over 66 million years, and if one day a dinosaur would evolve to Earth, it would be a very different world.

"An animal that went extinct naturally, maybe 150 million years ago, will not recognize anything in this world if you return it," Maidment noted. "What are you going to eat when the grbad did not?" [yet] evolved then? What is its function, where do we place it, does someone own it?

That said, it might be better to let the sleeping dinosaurs lie, he said.

Originally published in Living science.

Source link