Who needs a man? Not these birds.
In what could be seen as a last-ditch effort to save their species, scientists claim that two female California condors each spontaneously conceived two chicks — no papa required — within the previous two decades.
Unfortunately, both baby birds eventually died, in 2003 and 2017, but researchers have said the findings could help contribute to our understanding of when and why anomalous asexual births occur in some animals — as well as why these birds would have chosen to snub their perfectly available male pen mates.
Although rare, particularly in birds, several other animals — including, more recently, a number of reptiles, marine animals and insects — have been known to reproduce asexually under mysterious and extraordinary circumstances in a process called parthenogenesis, which scientists have only just begun to understand.
Like self-cloning, parthenogenesis occurs when an embryo becomes fertilized by a polar cell — that is, a cell that contains duplicate DNA from the female. In the absence of sperm and the male DNA, the female anatomy may instead take advantage of their polar cell as a supplement to the ovum and create life with two sets of the same DNA.
In a perfectly healthy and genetically stable animal, this can create a viable zygote with all the chromosomes required to create life.
Animal researchers at the San Diego Zoo published their report on the immaculate conception of two California condors, considered a “critically endangered” species, in the “Journal of Heredity” on Thursday, reported Gizmodo.
Oliver Ryder, San Diego Zoo geneticist and co-lead author of the new research, called it a “total goosebump moment.”
“It’s a remarkably improbable occurrence,” Ryder told Gizmodo. “In their lifetimes they weren’t even recognized to be parthenotes … we’re definitely keeping our eyes out anytime we get a batch of blood samples for testing.”
Clocking in at over 20 pounds with a wingspan up to 10 feet across, the California condor is North America’s largest bird. But despite their imposing stature and preference for scavenging already dead prey, the species has suffered a long decline due to habitat loss and other human activity. Today, just 201 adults individuals remain — 93 of which have successfully reproduced in their lifetime, which typically lasts less than 19 years, according to the International Union for Conservation of Nature.
The discovery of two new additions came during a regular census of the species, Ryder said. When their presumed fathers — and more than 480 other male birds — failed to match with the chicks, researchers deduced that parthenogenesis must have played a role.
While we certainly can’t rely on the very rare occurrence of parthenogenesis to save the species, it is a notable phenomenon for genetic researchers.
“We only now have the genetic tools to look at this in detail,” Ryder told Gizmodo.
“Previously, parthenogenesis was really identified by seeing females who weren’t housed with males have offspring. But now we know the condor can have offspring while being housed with males and it begs the question, ‘Is this going on more than we know?’”