Endangered birds experience 'virgin birth,' a first for the species (NatGeo)

[eppur_se_muova]

ByJason Bittel
Published October 28, 2021
• 6 min read

“There’s something really confusing about the condor data.”

Those weren’t the words Oliver Ryder wanted to hear as he walked to his car after a long day’s work trying to save California condors, one of the most endangered animals on the planet. When his colleague Leona Chemnick explained what she was seeing, his dread quickly changed to fascination.

For decades, scientists have been trying to coax the California condor back from the edge of extinction. The entire population of these birds crashed to just 22 animals in 1982. By 2019, captive breeding and release efforts had slowly built the total population up over 500. Doing that has required careful management of captive birds, particularly selecting which males and females can breed to produce healthy offspring.

That’s how, as the scientists took a closer at genetic data, they discovered that two male birds—known only by their studbook numbers, SB260 and SB517—showed no genetic contribution from the birds that should have been their fathers. (Read about virgin birth recorded in a reticulated python, the world’s longest snake.)

In other words, the birds came into the world by facultative parthenogenesis—or virgin birth—according to a peer-reviewed paper published October 28 in the Journal of Heredity. Such asexual reproduction in normally sexually reproducing species occurs when certain cells produced with a female animal’s egg behave like sperm and fuse with the egg.
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more: https://www.nationalgeographic.com/animals/article/in-extremely-rare-event-two-female-birds-make-babies-without-males

[Irish_Dem]

1. Perhaps as the number of males in a species dwindles, evolution favors asexual reproduction?

I wonder if these offspring are fertile?

[hunter]

2. Sex determination in birds doesn't work the same as it does in mammals.

In mammals such as ourselves having XX chromosomes generally makes an individual female, having XY chromosomes generally makes an individual male. Sex is determined by the father's sperm, which carry either an X or a Y chromosome.

In birds the sex chromosomes are called Z and W.

Generally males have ZZ chromosomes and females have ZW chromosomes.

That's how these birds are male.

https://en.wikipedia.org/wiki/ZW_sex-determination_system

If parthenogenesis ever occurred in mammals the offspring would be female.

[eppur_se_muova]

4. Interesting, thanks ! nt

[Walleye]

3. Tribbles, on the original Star Trek, were born pregnant I think

🖖

[Javaman]

7. the father, bird and the holy ghost.

[eppur_se_muova]

8. In this particular case, usage of the word "chick" is politically correct. nt