Asian Water Dragon Proves She Doesn't Need A Mate To Produce Fertile Egg

Scientists at the Smithsonian's National Zoo say a female Asian Water Dragon reproduced without a male — the first confirmed case for its species.

ARI SHAPIRO, HOST:

The Smithsonian's National Zoo here in Washington has a lot of female reptiles, and that means a lot of unfertilized eggs that don't hatch. Their policy was basically to toss them. But a few years back, they thought, why not try incubating some of the eggs?

KYLE MILLER: Because it doesn't take any time, we were like, oh, let's just try this with the eggs we get and see what happens.

MARY LOUISE KELLY, HOST:

That's Kyle Miller; he's a zookeeper who works with the zoo's reptiles. Almost all the eggs went bad after a few days, but the eggs of the Asian water dragon did not. So Miller and his co-workers held up a flashlight to the tiny eggs, looking for signs of life, specifically veins.

MILLER: Say you were to take, like, a marble that was completely white and draw little, tiny red lines on it. And that was enough for us to tell that the eggs were fertile.

SHAPIRO: This was huge. The female Asian water dragon had not been near any males in years. And you may remember from biology class, males are an important part of reproduction for most animals.

MILLER: We didn't believe it at first. We were like, wait a minute; are we seeing things here - because it was so unexpected.

KELLY: What they were seeing - or thought they were seeing - is facultative parthenogenesis, where females produce offspring without a contribution from a male. Eventually, one of the Asian water dragon's eggs hatched, Miller's colleagues ran a DNA analysis that confirmed their hunch.

SHAPIRO: Now, as impressive as this sounds, there are a number of other species that can do this - Komodo dragons, for example.

KELLY: Still, her keepers are really excited, and her achievement has earned her an honor that is usually reserved for such charismatic reptiles as tortoises and crocodiles.

MILLER: Typically, a lot of reptiles and amphibians don't have names in zoo collections. But since this was such a cool study, we named the mother dragon Saphira.

SHAPIRO: Saphira's daughter is still just an anonymous Asian water dragon. But if she can match her mom's reproductive prowess, she might get a name, too.

(SOUNDBITE OF SONG, "SINGLE LADIES (PUT A RING ON IT)")

BEYONCE: (Singing) All the single ladies, now put your hands up - whoa, oh, oh, oh, oh, oh. Whoa, oh, oh, oh, oh, oh, oh. If you like it, then you should've put a ring on it. If you like it, then you should've put a ring on it. Don't be mad once you see that he want it.

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