Today I found out squirrels can purr.

In September 2010 a baby squirrel named Rocky fell out of his nest in Mississippi. The family who found poor Rocky decided that their nursing cat, Emmy, would be the perfect mother for the little rodent. Rocky quickly became one of the litter and began to purr along with the other kittens. This little squirrel being taken in by a mother cat and developing the propensity to purr even made the local news. However, this isn’t news for wild animal rescue groups who have long known that squirrels could purr.

Other animals that have been said to purr include squirrels, rabbits, tapirs, lemurs, raccoons, gorillas and guinea pigs.  It should be noted, though, there is some contention over whether these animals can actually be considered to be purring.  The debate comes from the definition of the term “purr.”  Purr purists (I will refer to them as purrists) contend that the only true purr in nature is found in cat families (felidae), and two species of genets.  They state that a true purr is distinguished from a purr-like sound by the continuity of the purr during inspiration and expiration, with the animal needing to have the ability to make the sound go on continuously for minutes to be considered a real purr.

Since the noise these animals make does not meet the definition set forth by purrists, they say the noise is simply a purr-like grunt. In the case of the squirrel, it is thought that the purring noise is only audible on either inspiration or expiration and not both continuously, thus cannot be a true purr, by purrists standards.  Most, however, aren’t so strict on the definition, and contend if an animal can make a purring sound, they are able to purr.

Whether you’re a purrist and say the squirrel doesn’t actually purr, but only makes a purr-like noise, or you’re less “type-A” and are more in the “if it looks like a duck, and quakes like a duck…” crowd, I think we can all agree its adorable:  click here to hear a squirrel purr

Bonus Facts:

• The true mechanism that allows cats to purr has never been definitively proven. The leading theory is that the sound emanates from vibrating laryngeal muscles (the muscles that control the “voice box”). When these muscles vibrate, they open and close the glottis (the opening between the vocal cords), allowing for sound to be created on inspiration and expiration. Studies done in 1972 and 1991 have shown that cats have a unique “neural oscillator” that controls their laryngeal muscles. This oscillator provides the muscles a rhythmic and repetitive signal from the central nervous system. The ancillary evidence that cats with laryngeal paralysis do not purr also backs up this theory.
• Even though it is thought purring comes from the same place that other cat vocalizations do, purring is not considered a true vocalization like a “meow” or a “hiss.” This is because vocalizations are used to show specific emotions or physiologic states. Cats have been known to purr when severely injured, giving birth, put under physiological stress, as well as when content, such as when being petted. Because purring is produced under differing emotional states, it is not considered a true vocalization that expresses the particular emotional state.
• Squirrel meat was once so common as a food source in the United States that The Joy Of Cooking contained recipes for squirrel meat in its early editions. This practice is still so common in parts of the U.S. that in 2007 The New Jersey Department of Health and Senior Services issued a warning to limit consumption of squirrel meat for pregnant women and children, after a squirrel in the Ringwood area was found to have toxic levels of lead.
• Squirrels are found on every continent except Australia and Antarctica. They range in size from the African Pygmy Squirrel’s five inch span (nose to tail), to the Indian Giant Squirrel’s three-foot length.
• There is friendly competition for claiming the title of “White Squirrel Capital of the World.” Olney, Illinois has gone so far as to give white squirrels the right of way on all the streets in town, including a $500 fine for hitting one. It would seem no surprise then, that Olney is thought to have the world’s largest colony of white squirrels. The police officers’ uniform patches even feature a white squirrel. Other towns vying for the furry white crown include Brevard, North Carolina and Marionville, Missouri.
• One type of squirrel is known to be predatory and has been observed preying on chickens and snakes. This makes the Killer Bunny scene from Monty Python’s Holy Grail seem, all of a sudden, disturbingly possible. Do not run into the Thirteen-lined ground squirrel in a dark alley.
• Along those same lines, a fossilized skull resembling a “saber toothed squirrel-like creature” was found in 2002 in Argentina. This new species, called Cronopio dentiacutus, because of its extensive fangs and narrow snout, is the second oldest mammal skull ever found in South America. It ranged in size from 20-23 centimeters, or about 8-9 inches.
• The record for a cat falling from a height and surviving is 45 stories. Most cats will be injured from falls of 7 stories or more, but the vast majority will live falling from any height, so long as they receive medical attention after the fact.  You can read more about this here: Domestic Cats Can Fall From Any Height with a Remarkable Survival Rate
• It is commonly thought that cats were domesticated in ancient Egypt. However, in 2007 a study proved that the first domesticated cats roamed the Middle East around 10,000 years ago. In 2004, another cat was found buried with its owner at a Neolithic cite in Cyprus. Because the site precedes the Egyptian civilization, and with new genetic evidence, it is now thought that the cat was first domesticated in the countries surrounding the eastern Mediterranean.