Piloerection

February 28th, 2012 by Elizabeth

People who have seen Burrito in person often comment that he’s “fluffier” than the other chimpanzees at the sanctuary, and it is an accurate observation. The technical term for this fluffiness is piloerection. A chimpanzee is said to be pilo erect when his or her hair is standing on end due to anxiety or excitement. (Humans also experience piloerection when we get goosebumps, but it’s not as obvious since we have less hair.) When a chimpanzee is completely calm and relaxed, his hair lies flat against his body. Given that Burrito is rarely completely calm — he’s a pretty high-strung guy — it makes sense that he’s very often pilo erect.

I like the following photos because you can see how much of Burrito’s impressive size is body and how much is “fluff”.

13 Responses to “Piloerection”

  1. Angela Derriso says:

    Mr. B is certainly a very fluffy man. I wonder if his high strung nature is due to his past, or just being outnumbered by the girls. I suppose that could be a bit stressful for one lone male.

    Considering that humans have this same ability, though much reduced, it seems to be mostly caused by either temperature sensitivity, or more rarely fear. I’ve never gotten goosebumps when angry, or anxious.

    I will say this, a human would look ridiculous if we had the hair to pull off the pilo-erect look. Not nearly as impressive as an adult chimpanzee.

  2. diane says:

    Chimpanzee’s are territorial. Perhaps he goes on alert when people approach what he considers his territory-the space where he lives. Also as the only male he may be ‘mate guarding’ the females.

  3. Marcia Douthwaite says:

    With all the females, I am sure he needs to show some sort of dominance on occasion. Love the last photo, Elizabeth, a great display of Mr. Burrito!

  4. Linda (Portland, OR) says:

    WOW, those are great pics of Mr. B’s “fluff”.

    I’m sure the girls drive him crazy!!

    Thx for catching those Elizabeth!

  5. Teresa in TN says:

    wow, what a handsome dude Burrito is 🙂

  6. Denice says:

    I am always amazed at how muscular Mr. B is. He is a handsome male chimp.

  7. Burrito “smiles” a lot!

  8. Brenna says:

    Mr B looks so good in these pictures, especially the last one. It looks like he has wings on his back. I LOVE that guy. 🙂

  9. Sara Lissabet, Fairfax says:

    I’ve often noticed that fluffy hair (after all, he was born in the 80s – the decade of big hair 😉

    I thought it might be related to male display for females, such as we often see evidence in birds. I have often wondered how Mr. B is affected by being the only male in group of some pretty strong female characters.

    Were all or some of the chimps “cell mates” in the research facility? How well did they know each other while in the lab?

    • Elizabeth says:

      Burrito has always been a little intimidated by the girls (he is outnumbered, after all), but he seems to be getting more and more comfortable in the group.

      The chimps lived as a group at Buckshire for about two years before they moved to CSNW. I believe some of them crossed paths in various other labs as well.

  10. Patty says:

    Does Burrito ever relax enough that his hair lays down? He is such a hansom guy :o)

  11. marie cross (uk) says:

    super pictures and great info thank you , id never even thought to compare chimps hair fluffing up to our goosebumps ! fascinating xxx