Tag Archives: mass extinction

Condor Reproduction: The Splendid Capacity of Bodies

California condor in flight

Laurie and Debbie say:

We usually write about human bodies, but we were both fascinated by the news about condor babies born without fathers. We saw articles about this in many places, inckluding Sarah Zhang’s article in The Atlantic: “After Thirty Years of Breeding Condors, a Secret Comes Out.

California condors have been one of the most endangered species on the planet; their endangered species goes back to long before the current mass extinction pattern. Condor endangerment is entirely attributable to humans hunting these magnificent birds as trophies. In 1983, the condor population was down to 22 (!) individuals (it is now believed to be more than 300, still a pathetic number, many of them flying wild).

Because of the extreme situation of the condor, Zhang writes, “biologists have been carefully breeding the birds in captivity. They kept track of who mated with whom, how many offspring they had, and when those offspring were released into the wild. All of this is logged in the official California-condor ‘studbook.'”

It’s from these records that we now know that

scientists conducting DNA tests as part of routine research found two condors with unexpected paternity. These two birds—known by their studbook numbers as SB260 and SB517—were not related to the fathers recorded in the studbook. Actually, they had no fathers at all. A full 100 percent of their DNA had come from their respective mothers.

This single-parent reproduction is called parthenogenesis, and it has been known for a long time to be possible in various birds, including turkeys, though it hadn’t been documented before in condors. Most babies born this way (known as “parthenotes” are somewhat genetically deformed, including both identified condors: however, they both were born live and lived to early maturity. In other vertebrate species. Zhang says, “In boas and pythons, [University of Tulsa biologist Warren] Booth has been able to get female parthenotes to breed with males and have viable offspring. In the wild, parthenogenesis could help these reptiles recover from severe population loss. ​”

For us, that’s the exciting part. Mass extinction threats and severe population loss are happening to thousands of species all over the world–not all of them will be able to reproduce parthenogenetically (apparently, mammals can’t). And we certainly can’t take this as a reason not to fight climate chaos and protect biodiversity. Nonetheless, the possibility is a stunning testament to nature’s endless creativity and unpredictability. What other life-saving surprises could be lurking in the genes and proteins of living things?

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