Extinct animals might hold clues to the survival of today’s endangered species. That’s according to molecular biologist Stephan Schuster of Penn State. He recently sequenced a mammoth genome using DNA material that had been preserved in Siberia’s permafrost for tens of thousands of years.
Stephan Schuster: We generated complete sequences of their mitochondria – a teeny weenie bit of the genome that is only inherited from the mother.
Schuster and his team compared genes from 18 different mammoths. He discovered that these animals, which used to number millions, were divided into huge, genetically distinct families, hundreds of thousands of years ago.
Stephan Schuster: Then, the closer you get to extinction, you will find the same very similar individuals over and over again.
In other words, as the mammoth population grew smaller – partly, Schuster says, because of human encroachment – the mammoth population also got a lot less genetically diverse – and less resistant to stress. They finally eventually died off, he said. And, Schuster added, a number of today’s endangered species show this same lack of genetic diversity. He thinks they might be closer to extinction than we realize. He suggests a new strategy to help endangered species: using gene testing to identify good matches for breeding.
Stephan Schuster: Instead of just trying randomly and hoping for the best, we try to maximize the genetic diversity that is left in an already dwindling population. We present this as a new strategy, and we still feel we have a long way to go to also convince people who are in charge on those breeding programs that they will base their breeding on our genetic test.
Stephan Schuster talks about what he used to sequence the DNA.
Stephan Schuster: Usually you would sequence the genome by isolating the ancient DNA from bone, but in our instance we came up with a new method that we would use hair that was found in the permafrost from the mammoth.
Stephan Schuster noted that his sequencing of the mammoth genome is not 100% complete. But, he said, if one was:
Stephan Schuster: There are two routes how you could re-engineer a mammoth. One would be you create a complete sequence a computer, and if someone invents a printer that prints the DNA in the computer into functioning working chromosomes that could then be put back into an empty Asian elephant egg, the egg is put into an elephant surrogate mother – one at least in theory could envision a mammoth being born.
He said in 2005 this was thought almost impossible, but he now believes a ‘mammothified’ elephant might be only 10 or 20 years away.
Stephan Schuster : As we speak about resurrecting the mammoth, there are hundreds of species going extinct and because they are not as attention catching as the mammoth, we don’t care.
Schuster also emphasized that we should try to keep species off the endangered list at all, principally by maintaining habitat, and stopping the destruction habitat.
Stephan Schuster As we speak, more orangutans are living as pets in somebody’s house than living in the forest where they’re supposed to be. This is step number one.
Beth Lebwohl researches, writes and helps produce science content in audio and video formats for EarthSky. She is one of the authors on EarthSky.org, a script-writer for our podcasts, and helps host our English science podcasts in 90-second, 8-minute and 22-minute formats. Beth came to EarthSky in 2006 from the American Museum of Natural History's Department of Astrophysics, where she was surrounded by some of the greatest telescope-building, equation-wielding, code-writing physicists of our time. And they made her think . . . this science thing . . . it's pretty cool.