Reproduction without males: parthenogenesis in the California condor

Parthenogenesis rarely occurs in vertebrates: it can be observed in sharks, rays, and lizards, among others. Scientists have also discovered this phenomenon more frequently in some captive bird species where the females are separated from the males – for example turkeys, chickens, and pygmy quails. However, the fact that female California condors are also capable of parthenogenesis is a new discovery.

For Oliver Ryder, the strangest aspect of this particular case is that the birds bearing the numbers SB260 and SB517 come from different mothers who not only lived with the males, but mated successfully – both before and after their first birth.

“What happened there? We don’t know,” Oliver Ryder says. “We just know it has happened a few times and in different women — and I think it will happen again.”

Virgin Birth: Rescued from Extinction?

Currently, just over three hundred California condors fly freely across the skies over California, Arizona, and Utah. according to Reshma Ramachandran, a reproductive physiologist and microbiologist at Mississippi State University in Starkville, may have caused parthenogenesis in the species — as a survival aid, so to speak. Ramachandran was not involved in the study.

Facultative parthenogenesis has also been observed in other animal species in distress. For example, females of the critically endangered narrow-tooth sawmill, now breed without males due to the increasing shortage of sexual partners.

Whether this theory can be applied one-on-one in the case of the California condor is debatable. This is countered by the fact that in the females in which the virgin generation occurred, the possibilities of males and therefore mating were available. In addition, none of the males that resulted from parthenogenesis managed to survive long enough to reproduce on their own. SB260 died at age two, SB517 shortly before sexual maturity, which he would have reached at age eight. California condors can live up to 45 years.

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