Rediscovered Red Wolf Genes May Help Conserve the Species

Rediscovered Red Wolf Genes May Help Conserve the Species
A captive red wolf pup at the Durham Museum of Life and Science. Credit: Jason Pulley/Alamy Stock Photo

A surprising new gene discovery in coyotes may help conserve the critically endangered wolf.

Fionna M. D. Samuels: This is Scientific American’s 60-Second Science, I’m Fionna Samuels.

The red wolf once roamed a huge swath of the eastern United States. These rust-colored canines once roamed the entire length of Long Island, Missouri, and down to Texas-Mexico. But by 1972 the population was reduced to only roaming a small area along the Gulf coast due to habitat loss and hunting.

To conserve the species, 14 individuals were captured as part of a breeding program. In 1980 their wild relatives were declared extinct–the captured wolves were all that was left.

Kristin Brzeski: The species has gone through this huge bottleneck and through that lost a lot of genetic variation. Because there are so few founders, there is a lot of inbreeding.

Samuels: That’s Kristin Brzeski, an assistant professor at Michigan Technological University, whose research focuses on the conservation of genetics of wild animal populations.

Brzeski: I think, what captures the imagination with the red wolf, and I think this work, is it, it’s been the underdog. It’s been the underdog scientifically, and it’s been the underdog in conservation. It was, you know … all wolves were heavily persecuted, but the red wolves were heavily persecuted to the point that only 14 were left.

Samuels: Now, Brzeski and her collaborators have found a surprising new pool of red wolf genes that might help bring more diversity to the tiny population: ghost alleles in wild coyote populations.

Alleles are the parts of a chromosome that encode specific genetic traits. Canines inherit one of each parent’s alleles for a particular gene, just like humans. These are sometimes called “ghost” or “ghost” alleles.

Bridgett vonHoldt: So the ghost part is the red wolves are gone, and we presumed they took all of their genes with them. We must also remember that if a population is declining, it might find its best mate in the next closest species. A coyote and a red wolf can have offspring. The red wolf may die, as that’s what has been happening for redwolves. However, all the genes it passed on to its hybrid red wolf offspring, are now in circulation and we’ve rediscovered them.

Samuels: Bridgett vonHoldt, who you just heard, is a collaborator working with Brzeski. Together, they found that some coyote populations in Louisiana and Texas who were protected from hunting still retain huge amounts of red wolf genes–some individuals are almost 60% red wolf.

Red wolves can be released back into the wild and bred with coyotes to help them regain some genetic diversity. That’s almost like going back in time and un-doing the genetic bottleneck from 1980–making the new red wolf population more genetically diverse.

vonHoldt: This would be kind of the opposite direction, taking the small isolated, you know, inbred population from the captive breeding program that still has red wolf genes that are so critical, and put them into a wild landscape with new genetic variation that they haven’t seen for 50 years or more. This is a super mixture of genetic health and a rebound so that the animals can be wild again.

Samuels: The next steps will include how to release red wolves in a way that takes advantage of the ghost alleles hiding in coyote populations. There might be some resistance, as with other wolf-releasing efforts.

vonHoldt: There will be controversy, there will be people who aren’t happy. There are many people who are supportive and kind. And I believe that at the end of it all, there is a philosophy that we created the problem and are responsible for fixing it.

Samuels: For Scientific American’s 60-Second Science, I’m Fionna Samuels.

[The above text is a transcript of this podcast. ]


    Fionna M. D. Samuels was a 2022 AAAS Mass Media Fellow at Scientific American. She is currently pursuing a Ph.D. degree in chemistry at Colorado State University. Follow her on Twitter @Fairy__Hedgehog

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