Are Dinosaurs Coming Back To Earth?

Most of us have seen the Jurassic Park movies and have been fascinated by them. Some of us have even wondered if ‘de-extinction’, or bringing back a species after it has gone extinct is possible. You’ll be surprised to know that the idea behind the movie wasn’t just the imagination of a fantasy writer. Scientists have actually devised a method to bring back the dinosaurs!

Science journalist Helen Pilcher wrote about this strange idea in her book “Bring Back the King: The New Science of De-extinction.” In the 1980s, John Tkach and some of his fellow scientists, who called themselves the Extinct DNA Study Group, put forward the idea of an intriguing experiment.

Many millions of years ago, there might have been a mosquito that bit a dinosaur and then became trapped in amber, with the dinosaur blood still in its stomach. If one could recover a dinosaur blood cell from the bug and transplant it into an egg which has had its DNA removed, it might be possible to “regrow” a dinosaur. This theory sounds very far fetched, but it wasn’t in fact that crazy.

Entomologist George Poinar at University of California, Berkeley, has spent his career studying apps trapped in tree resins that have hardened into amber. In 1980, he came across a fly that “defied expectation”, with cells still intact. When Poinar’s findings were published, it excited the scientific community, and a “tall, gangly gentleman” often visited Poinar to ask about his research. This gentleman turned out to be the author of the book Jurassic Park, and used his conversations with Poinar as the scientific basis for the novel.

So what do we know today, decades later?Pilcher writes in her book that “A modern living dinosaur is not a fantasy.”

While there are scientists who like to believe this is possible, there are challenges. To make any animal de-extinct, you need a source of the animal’s DNA. However for dinosaurs, all we have are fossils and once an animal is fossilized, all organic material is destroyed. However, starting in 1992, paleontologist Mary Schweitzer made a series of discoveries including the fact that dinosaur fossils “contain molecules that were present in their red blood cells,” and that certain types of tissue could “survive fossilization”. She further determined that some protein molecules had survived as well. This was the first step in collecting dinosaur bits to regrow them.

“Although dinosaurs were made of protein (and many other molecules), we can’t somehow regrow one from a few bits of collagen,” writes Pilcher. DNA molecules are required for the scientists to start cloning dinosaurs, and it was found that DNA has a half-life of 521 years. This means after approximately 6.8 million years, DNA molecules will be completely destroyed.

Some scientists including Schweitzer’s boss, Jack Horner, believe that dinosaurs could be reconstructed in other ways. Horner was the scientific advisor for Jurassic Park and he believes that he could grow a dinosaur quite fast by running evolution backwards.

Both chickens and alligators are evolutionary descendants of the theropod, a category of dinosaurs including the T-rex. Horner’s idea involves taking a bird embryo and somehow bringing out its ancient characteristics. Kind of like hatching chickens that develop dinosaur like features.

Currently, there are programs that are trying to de-extinct creatures like the dodo, the passenger pigeon, and the woolly mammoth but they haven’t been too successful. Lack of DNA, no proper incubation environment, and the risks posed to species that serve as surrogates are major problems. However, on a more positive note, the science of de-extinction might help endangered species not become extinct over the years.