What evolutionists talk about: an email conversation between Matthew and me

First Matthew sent me this tweet showing a thieving moggie and his haul of socks and underwear (check out the original tweet to enlarge the photos).

This email exchange ensued:

Jerry:  What a diligent cat!

Matthew: Why do they do it?

Jerry: You’re asking me to enter a cat’s brain?

Matthew:  What better place to be? Apart from the fact you have to lick your butt.

Jerry: LOL! They LIKE to do that!

Matthew: How do you KNOW?  They HAVE to do it, but do they LIKE it?

Jerry:  As you surely know, Dr. Cobb, evolution makes us like what we have to do. Orgasms are the prime example; maternal behavior another. I am making an informed guess here.

Matthew: Hmm. I think a more parsimonious explanation is that they don’t like the smell so they have to lick their butts. They may not not like it, but like the outcome.

Jerry: I’m putting our conversation in a post. Now.

Matthew: Fine. I’m right!

Is he?


  1. Frank Bath
    Posted November 12, 2017 at 2:40 pm | Permalink

    I’d say you were. The cat’s butt is up the other end from its nose so smell can’t be that much of an issue. But what do I know?

  2. Posted November 12, 2017 at 2:41 pm | Permalink

    I don’t know who is right, but all the socks and undergarments in the photo look like they belonged to men. Why would a cat selectively pilfer male belongings? Suggests that staff fibbed a bit, cat only had access to male clothes, or cat preferred male over female goods.

    • Posted November 12, 2017 at 3:11 pm | Permalink

      Ummm. . . they also look like one person’s undergarments. Have you considered the possibility, suggested in the flyer, that the cat steals from the nearest neighbor, and that neighbor is a man who lives by himself???

      • Posted November 12, 2017 at 3:32 pm | Permalink

        No, I hadn’t. But that could be.

        If the thieving is about the proximity to a male who perhaps leaves his clothes on the line too long or leaves his door open, maybe that is it.

        Just means cat is as much of an opportunist as a compulsive garment-gatherer.

        But that, constrained by enivonment & predisposition, could describe almost anyone in any circumstance. #Determinism.

  3. Posted November 12, 2017 at 2:48 pm | Permalink

    I am just killing myself laughing at the cat butt!

    • BJ
      Posted November 12, 2017 at 8:03 pm | Permalink

      From Fecal Products Amalgamated comes Cat Butt®, the new product from the company that brought you Poop Chute®!

      FPA, a subsidiary of the M. Havisham Wigs & M. Olivier Nuclear Materials Conglomerate. “The finest wigs from the materials you least expect.”

      Editor’s note: The conglomerate’s name contains two references to fictional works, and while the first should be immediately obvious, I wonder if anyone will guess the second. Hint: like this bit of fun, it’s a mystery!

  4. Jake Sevins
    Posted November 12, 2017 at 2:49 pm | Permalink

    This is what evolutionary biologists think about after retirement… hmm…

  5. Randall Schenck
    Posted November 12, 2017 at 2:49 pm | Permalink

    Cats also lick your face. So they lick their butts so you can guess which they licked first.

  6. Craw
    Posted November 12, 2017 at 2:50 pm | Permalink

    But why does Reza Aslan lick his own butt?

    • BJ
      Posted November 12, 2017 at 7:43 pm | Permalink

      OH SNAP

  7. GBJames
    Posted November 12, 2017 at 2:51 pm | Permalink


  8. jaxkayaker
    Posted November 12, 2017 at 2:55 pm | Permalink

    I don’t know whose hypothesis is correct, but I have some ideas about how to test them. We’ll just need some money from NSF.

  9. Ken Pidcock
    Posted November 12, 2017 at 3:03 pm | Permalink

    I’d say he is but, inasmuch as I can’t lick my own but, I can’t be sure.

  10. ThyroidPlanet
    Posted November 12, 2017 at 3:22 pm | Permalink

    Things in excrement :

    I propose they are at work as well.

  11. Posted November 12, 2017 at 3:22 pm | Permalink

    A cat’s butt often itches if it’s not clean, so they therefore lick it clean. And Mama did it, so why not continue.

  12. yazikus
    Posted November 12, 2017 at 3:43 pm | Permalink

    Explaining the natural world, one cat-butt-lick at a time!

  13. Posted November 12, 2017 at 4:25 pm | Permalink

    I would argue we don’t always like what we have to do. Really needing to go to the loo for example, is all about the alleviation of discomfort.

    • Gregory Kusnick
      Posted November 12, 2017 at 5:10 pm | Permalink

      Similarly, if you’re sick or injured, you have to rest up to recover, but you don’t have to like it.

    • Posted November 13, 2017 at 5:46 pm | Permalink

      Which is why I side with Matthew. It shouldn’t be too hard in principle to test: just stick a cat in an fMRI at the right moment, and see which parts of the brain light up. Of course, this faces the minor detail that it involves herding cats. 😉

      • Diana MacPherson
        Posted November 13, 2017 at 6:00 pm | Permalink

        Except that you can’t move while in an fmri to get the results, so licking your butt will be impossible.

  14. wayne
    Posted November 12, 2017 at 4:30 pm | Permalink

    well, THAT certainly was not a waste of time!

  15. Taz
    Posted November 12, 2017 at 5:05 pm | Permalink

    Where was the cat hiding his stash?

  16. Torbjörn Larsson
    Posted November 12, 2017 at 5:12 pm | Permalink

    And here I thought they licked their but because they can reach it.

    More seriously, cats lick their coats, birds pick their feathers, and monkeys pick their hairs, despite all the gross things in there. In the two latter cases it is believed they relieve itches and/or gets rid of parasites. E.g. cats have hook worms, from severe to asymptomatic infestations: http://www.petmd.com/cat/conditions/infectious-parasitic/c_ct_ancylostomiasis .

    • Torbjörn Larsson
      Posted November 12, 2017 at 5:13 pm | Permalink

      But I can’t spell “butt”.

    • ThyroidPlanet
      Posted November 12, 2017 at 5:51 pm | Permalink

      Ah so why couldn’t any of the things cat takes into its mouth from its anus – bacteria, viruses, yeast – keep bad things like parasites from sickening the cat?

      …. unless I am mistaken about the definition of “butt”..

  17. Stephen Barnard
    Posted November 12, 2017 at 6:22 pm | Permalink

    What is it Like to be a Cat?

  18. BobTerrace
    Posted November 12, 2017 at 6:33 pm | Permalink

    There are people who like to lick butts, although not their own (not physically possible, as far as I know).

    Someone start a research project and ask them.

  19. Igor
    Posted November 12, 2017 at 6:55 pm | Permalink

    How many licks does it take to get to the center of it?

  20. Posted November 12, 2017 at 6:59 pm | Permalink

    I’m in the middle of watching the movie, “The Man Who Knew Infinity”, and the main character, Srinivasa Ramanujan, a gifted Indian mathematician, is asked why he keeps working on complex theorems. He answers, “Because I have to.”

  21. Heather Hastie
    Posted November 12, 2017 at 7:01 pm | Permalink

    Sorry Jerry but I think Matthew’s got this one! They do it because they have to, not because they like it.

  22. Larry Smith
    Posted November 12, 2017 at 7:23 pm | Permalink

    Don’t they do it because over time the cats (and their predecessors) who have cleaned themselves thusly (cannot bring myself to write “licked their own butts” – oops!) have gained some sort of reproductive advantage by so doing? As in avoiding disease, detection by predators, etc.?

    Or was that assumed all along and it’s just a “do they enjoy the process” vs “do they enjoy the result” debate?

    • Adam M.
      Posted November 12, 2017 at 7:35 pm | Permalink

      I think the question is “How did natural selection mold cat brains to produce this behavior? By making licking pleasant, or making not licking unpleasant?”

  23. BJ
    Posted November 12, 2017 at 7:45 pm | Permalink

    Why do any of us lick our own butts? We all have our reasons.


  24. Diana MacPherson
    Posted November 12, 2017 at 8:42 pm | Permalink

    I think they like it once they start but they wouldn’t donitbif they didn’t feel discomfort. It’s like itching a mosquito bite. I don’t like itching per se but it feels good when I itch a mosquito bite.

    • Diana MacPherson
      Posted November 12, 2017 at 8:43 pm | Permalink

      Do it. Not whatever that word was.

  25. danstarfish
    Posted November 12, 2017 at 9:32 pm | Permalink

    What a cute cat. My tonkinese cat is very mischievous too, though she has never stolen garments from the neighbors.

  26. Posted November 13, 2017 at 1:58 am | Permalink

    Nice of the cat to lay them all out so neatly too.

  27. Dani
    Posted November 13, 2017 at 4:37 am | Permalink

    This is so lovely: https://imgur.com/gallery/JR3MaqO
    it looks like a post you might like!

  28. Josh Lincoln
    Posted November 13, 2017 at 10:41 am | Permalink

    Cats, unlike dogs do not tend to exhibit coprophagic tendencies. So it would seem that they don’t particularly enjoy the taste. I propose that they those that lived to evolve did so due to the fewer amount of resident potential pathogens that they were carrying around. But, (pun intended) I think that the main reason is that occasionally cats can get stool matted in the fur around their rectum that can lead to an obstructive condition that could be potentially life threatening in the wild. This is particularly true for slightly longer haired cats. The matted stool becomes almost petrified and if no the dealt with promptly can make be quite a problem.

    • Posted November 13, 2017 at 5:27 pm | Permalink

      Other long haired animals have this cleanliness problem, such as sheep. Watch sheep shearing. Cows and horses and, no doubt,other animals have this problem (including some humans). The factory farms causes cows, pigs and chickens to have such problems. Cats clean the way they do because they can. Other animals don’t have that option. Humans have come up with a variety of solutions for cleaning behinds such as sponges on sticks, corn cobs, catalogs, weeds, left hands, TP, etc. In some parts of the world, few such options are available so they try to cover the stench with perfume. I understand that’s quite the olfactory experience.

  29. Posted November 13, 2017 at 11:51 am | Permalink

    While “evolution makes us like what we have to do”, it is not so clear that cats MUST lick their butts or risk their species going extinct. Also, there are plenty of things that are good for us to do but we generally don’t like: exercise is a good example, changing a diaper is another. Mothers do many things that they don’t particularly like out of a sense of duty, a drive undoubtedly provided by evolution. As usual, things are complicated.

  30. Liz
    Posted November 13, 2017 at 2:06 pm | Permalink

    I don’t know about the cat. This makes me wonder in what species pleasure associated with reproduction first started happening.

    • Posted November 13, 2017 at 3:36 pm | Permalink

      I suspect it started with the first sexually reproducing species. To think otherwise is to consider rape. Of course, it is also possible it started with indifference or boredom. I hear that still happens.

      Actually, a harder question to answer is whether there was a first sexually reproducing species. What lies between asexual and sexual reproduction?

      • Liz
        Posted November 14, 2017 at 12:43 pm | Permalink

        Thanks so much. That makes sense. I think more specifically maybe what I was trying to ask was in what species was the pleasure portion first able to be measured. If it was in the first sexually reproducing species, was it less than it is now? Does the pleasure portion of reproduction keep increasing and increasing with each species? What determines that?

        • Posted November 14, 2017 at 12:48 pm | Permalink

          Yes, I’ve often wondered that also. I suspect that pleasure is always involved no matter the species. It is evolution’s way of making us do things that are beneficial to survival and reproduction. Instead the question becomes which species feel pleasure like we do, or how does each species experience pleasure? Now that’s a really hard question to answer.

  31. infiniteimprobabilit
    Posted November 14, 2017 at 1:59 am | Permalink

    Story I read once –

    Pompous lecturer: So, humans, who have evolved as a general-purpose species, can do anything that the more specialised mammals can do, albeit not quite so skilfully. For example, is there anything a cat can do that a human cannot?
    Sarcastic voice from back of class: Lick its arse!


%d bloggers like this: