« This Day In History: Aug. 1 | Main | This Day In History: Aug. 2 »

When a Mule Foals


A mule in Colbran, CO, reportedly gave birth to a foal in April. Genetic testing has verified that the as-yet-unnamed foal is indeed the mule's offspring.

A Denver Post article explains the significance of the event (believed to be so rare that the Romans apparently had the saying "when a mule foals"):

The foal is being called a miracle because mules aren't supposed to give birth. Mules are a hybrid of two species—a female horse and a male donkey—so they end up with an odd number of chromosomes. A horse has 64 chromosomes and a donkey has 62. A mule inherits 63. An even number of chromosomes is needed to divide into pairs and reproduce.

Testing done in a previous observed case revealed that the foal, the offspring of a mule and a donkey, was itself a mule, with 63 chromosomes. The outcome of testing to determine whether this latest foal is a mule, a donkey, or a mix of the two, is pending.

"Mule's Foal Fools Genetics" (The Denver Post)
"Morocco's Miracle Birth 'Confirmed'" (BBC News)
"Male Mule Foal Qualifies as the Offspring of a Female Mule and Jack Donkey" (Journal of Heredity, purchase required)

Photo: Horse and Mule by eliotphillips.


TrackBack URL for this entry:

Post a comment

(If you haven't left a comment here before, you may need to be approved by the site owner before your comment will appear. Until then, it won't appear on the entry. Thanks for waiting.)


This page contains a single entry from the blog posted on August 1, 2007 10:31 AM.

The previous post in this blog was This Day In History: Aug. 1.

The next post in this blog is This Day In History: Aug. 2.

Many more can be found on the main index page or by looking through the archives.

Creative Commons License
This weblog is licensed under a Creative Commons License.