Befuddling Birth: The Case of the Mule's Foal Mules — the offspring of female horses and male donkeys — are generally sterile and can't reproduce. But a female mule in Colbran, Colo., has recently become a mother, and her owners are trying to figure out how it happened.
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Befuddling Birth: The Case of the Mule's Foal

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Befuddling Birth: The Case of the Mule's Foal

Befuddling Birth: The Case of the Mule's Foal

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There's news and then there's news. This next story is really big news. In the online edition of Mules and More - that's the monthly for mule and donkey enthusiasts, but of course, you knew that - and the news is that a mule in Colorado has given birth.

And to put that in context, the Mules and More tells us that when the Romans wanted to say the equivalent of that'll happen when hell freezes over, they would say, in Latin, of course, that'll happen when a mule foals, in other words, when the sterile hybrid offspring of a female horse and a male donkey gives birth. It's just not supposed to happen.

There are accounts of it happening every few years everywhere from Albania to Morocco to Nebraska, and now it has happened in Colbran, Colorado. That's where Laura Amos and her husband, Larry, owned Winterhawk Outfitters and where they owned many mules. And one morning three months ago, one of them, a mule named Kate, astonished the Amoses when they woke up and found her with a newborn foal.

LAURA AMOS: We could tell visually there was no doubt that this mare mule had just given birth because we knew there will - would be skeptics and we knew that it was, you know, such a rare event. We had hair samples sent to the University of Kentucky that verified that this was a parent and offspring, and then we also had blood work sent to University of California at Davis, which also verified that it was a mule and her offspring.

SIEGEL: Well, it's not supposed to happen from whatever at the number of chromosomes that a mule comes away with from its parents, a horse and a donkey, should not permit fertilization - successful fertilization. So what kind of explanations have you had from people as to why this has happened?

AMOS: I'm waiting for an explanation. Yes, you're right. Mules are hybrid animals. They are the result of breeding a mare horse to a donkey. Horses, as you probably know, have 64 chromosomes and donkeys have 62. The resulting hybrid offspring - a mule - has 63 and they are infertile.

I think that further genetic testing will give us more certainty as to how this happened. But, I guess, there are a couple distant theories, and it would depend on what genetic information the mother passed on. This baby could perhaps be a mule. It could be a 63-chromosome animal. It could be a donkey or it could be what's known as a chimera. And that's an animal that has genetic bits and pieces, from my understanding, from other species.

SIEGEL: But whatever - and it's a he, yes? This is a...

AMOS: Yeah, it's a john mule.

SIEGEL: A john mule. Whatever he is, he's pretty rare.

AMOS: He's very, very rare. Yes.

SIEGEL: What are you going to do for him? Is he going to be an animal you'll exhibit or just going to use him as pack animal or what the...

AMOS: Well, you know, my husband says we got to get her back up on the mountain to get to work, but...

SIEGEL: Kate, that is, yes?

AMOS: Yeah, Kate. But I'm going to override him in this decision. My thoughts are she's not going to be a pack animal anymore. And I don't know, maybe I'll end up looking for an agent for her.


AMOS: Isn't that funny. So I really don't know at this point.

SIEGEL: Well, Laura Amos, thank you very much for talking with us today.

AMOS: You're welcome.

SIEGEL: That's Laura Amos of Colbran, Colorado, the owner of Kate, the mule, who, despite some pretty heavy odds against it, gave birth.

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