'Life found a way': National Zoo's Asian water dragon reproduces without male input

WASHINGTON (ABC7) — The Smithsonian’s National Zoo has confirmed that a female Asian water dragon has reproduced a healthy offspring without any contribution from a male.

It’s the first confirmed case in this lizard species of what scientists call facultative parthenogenesis, according to a release from the Smithsonian.

The mother Asian water dragon came to the Reptile Discovery Center at the National Zoo from the St. Louis Zoo. She was four months old when she arrived in November 2006 and was not intended to be a breeder.

Female members of the Agamid family, which includes Asian water dragons, have been found to lay infertile eggs even if they have not bred with a male. When the new mother first produced eggs in 2009 they were discarded by keepers, following protocol.

But in 2015, keepers began to incubate her eggs. After two weeks, they held them up to a light and discovered veins, indicating that the eggs were fertile and embryos were developing.

In the first two clutches of eggs, the embryos didn’t survive, but they were fully developed inside the eggs.

Then on August 24, 2016, a healthy female hatchling from the third clutch came out of her shell.

DNA and tissue and blood samples from the hatchling and the deceased embryos were sent to scientists at the Smithsonian Conservation Biology Institute’s (SCBI) Center for Conservation Genomics.

The Smithsonian's National Zoo and Conservation Biology Institute staff published their findings in a PLOS ONE paper on June 5, along with their partners from the St. Louis Zoo in Missouri and the University of the Sunshine Coast in Australia.

“The question we wanted to confirm was whether the Asian water dragon’s offspring had genetic material from only one parent—mom—or two parents—mom and a mystery male,” said Robert Fleischer, head of SCBI’s Center for Conservation Genomics and an author on the paper.

“In all of our tests, we found that the daughter only had one allele. If egg and sperm fusion had occurred, the offspring would have two alleles. It was very clear to us that the mother’s eggs were developing directly into offspring without assistance from a male.”