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Monday Pets: Where Did Cats Come From?

The views expressed are those of the author and are not necessarily those of Scientific American.


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ResearchBlogging.orgLet me tell you a little story. When I was born my parents had two cats. One was named Garfield. The other…well, I don’t remember what the other one was called. Not long after I was born, and little Jason was coughing up furballs, the doctors informed the parents that their little bundle of skin and hair was allergic to cats. It was then that teams were picked and lines were drawn. It was me or the cats. Luckily, the parents decided to keep me, and lose the cats. Imagine how much it would have sucked if they decided to keep the cats and lose me. I imagine if my younger brother had actually been my OLDER brother, he might have lobbied for the cats.
evil cat.jpg

Figure 1: I like to imagine that the cats were not happy about this, and decided to wage eternal war.

And despite losing the battle of who got to live with the Mommy and Daddy Goldman, I think the cats are still trying to win the war. The thing is, I’d like to make peace with the cats. But every time I go near a cat, my eyes water, my throat gets all scratchy, I start sneezing. It’s really pretty unpleasant. I once worked at a beautiful conference center near Los Angeles. And some very kind person had decided to donate their used couches to the institute. The couches were very comfortable, and so I decided to take a nap on one of them, one day. Within minutes, the all too familiar eye-watering and throat-scratching began. And I thought to myself: “these people had cats.” How thoughtless of them to have donated their couches without at least having them cleaned. Or at least a minimal vacuuming. And then, I thought to myself: “evil cats probably orchestrated the whole thing!”
So, dear reader, it’s not that I think cats are bad, per se. It’s that cats have decided to wage holy war on me, for ousting them from their former place of reverence. And that is seriously bad times.
But because I love my readers more than I loathe cats, I set out today to learn some things about cat cognition. I spent two hours at a cafe (with poor service, good coffee, and free wifi) crawling through PubMed, Google Scholar, JSTOR, Web of Science…to no avail! And I think the reason I wasn’t able to find very much on cat cognition is because…there aren’t very many people studying cat cognition in the first place! Sure, I found a random study here and there, but nothing particularly interesting. No titles or abstracts that made me think “wow, this is really interesting.” No extended lines of research.
And that got me thinking. Why were cats domesticated in the first place? And how?


We have some pretty good information on the domestication of dogs, and some really convincing hypotheses for how dogs carved a social niche for themselves in human culture. Decades of work on domesticated silver foxes in Russia have provided really important and interesting evidence that the many differences observed between dogs and wolves can be traced to a simple breeding rule: individuals that are not scared of or aggressive towards humans get to breed. As I wrote before (at the old wordpress blog):

These experimental foxes, which were bred on a single selection criteria, displayed behavioral, physiological, and morphological (e.g. physical/visible) characteristics that were not found in the control foxes, or in some cases, such characteristics were displayed with far higher frequency in the experimental group.
Behavioral changes: The experimental foxes were more eager to hang out with humans, whimpered to attract attention, and sniffed and licked their caretakers. They wagged their tails when they were happy or excited. Does that sound like your pet dog at all? Further, they had reduced fear responses to novel items or situations, and had enhanced exploratory behavior in unfamiliar situations.
Morphological changes: These changes were perhaps the most surprising. A much higher frequency of experimental foxes had floppy ears, short or curly tails, extended reproductive seasons, changes in fur coloration, and changes in the shape of their skulls, jaws, and teeth. They also lost their “musky fox smell.”
Physiological changes: The first change detected was in the (hypothalamic-)piuitary-adrenal axis. This system is responsible for the control of adrenaline, among other things. Adrenaline is one hormone that is produced in response to stress, and controls fear-related responses. The experimental foxes had significantly lower adrenaline levels than their control-group cousins. The researchers hypothesized that foxes that are not afraid of humans are going to produce less adrenaline around them. This explains the foxes’ tameness, but it doesn’t account for their changed fur coloration patterns. The scientists theorized that adrenaline shares a biochemical pathway with melanin, which controls pigment production in fur.
And so it was that selecting for a single behavioral characteristic – tameness (or, put another way, selecting against fear and aggression) – resulted in changes not only in behavior, but also in correlated and unselected physical and physiological changes.
These results have led to speculation that similar models could account for the superior behavioral and cognitive traits (and physical and physiological differences) of domestic dogs over their wolf ancestors.

In a 2007 Science paper, Carlos A. Driscoll and colleagues analyzed the mitochondrial DNA of 979 domestic cats and their wild cat cousins: Felis silvestris silvestris (European wildcat), F. s. lybica (Near Eastern wildcat), F. s. ornata (central Asian wildcat), F. s. cafra (southern African wildcat), and F. s. bieti (Chinese desert cat). They found that each wild group constituted a sub-species of Felis silvestris.
sylvester_the_cat.JPG

Figure 2: I want to note how awesome it is that the creators of Looney Tunes thought fit to name their cartoon cat Sylvester after the actual taxonomic title for the cat family.

They also found that cats were probably initially domesticated in the Near East, around the time that agriculture began in the Fertile Crescent. Mitochondrial genetic analyses showed that domestic cats are likely descended from five mother cats from this region, whose descendants were transported across the world by humans. The earliest evidence of cat-human interaction comes from archaeological remains in Cyprus dated to around 9500 years ago. This is somewhat later than the first evidence of dog-human interaction: the jawbone of a domestic dog was found in a late Paleolithic grave in Germany, and dated to around 14 thousand years ago. And there is the site at Ein Mallaha in Northern Israel where an elderly human and a 4-5 month old puppy were buried together, 10- to 12-thousand years ago.
cat phylogeny.jpg

Figure 3: Phylogenetic tree of mitochondrial DNA for wild and domestic cats. Labels A, B, C, D, and E represents the five original domesticated cat ancestors.

So dogs were domesticated on the basis of their ability to socially engage with humans. One might expect that similar processes are responsible for observed differences between domesticated cats and their wild cat ancestors. And, indeed, domesticated cats are tamer compared to their wild cat ancestors, and also show diversity in coloration, as do dogs. One important difference between domesticated cats and all other domesticated species is that domesticated cats are not neotenous (literally, baby-like). All other animals that have been successfully domesticated show physical features similar to human babies – proportionally larger heads, bigger wider eyes, larger foreheads. Since human adults innately respond to those characteristics in human babies, it makes sense that domesticated animals would share some of those characteristics. Animals that showed those physical characteristics would be more likely to receive care and attention from humans than those that did not have those baby-like features. But this is not the case with cats. The limited research that has been done on human-cat interaction has shown that cats do not readily socially engage with humans, unlike dogs, primates, sometimes horses, and even dolphins and whales (to some extent) and other marine mammals.
For example, a 2005 study by A

Jason G. Goldman About the Author: Dr. Jason G. Goldman received his Ph.D. in Developmental Psychology at the University of Southern California, where he studied the evolutionary and developmental origins of the mind in humans and non-human animals. Jason is also an editor at ScienceSeeker and Editor of Open Lab 2010. He lives in Los Angeles, CA. Follow on . Follow on Twitter @jgold85.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. ecologist 8:08 am 05/3/2010

    you just know someone is going to post this, so it might as well be me:
    http://boop.org/jan/justso/cat.htm

    Link to this
  2. 2. Arren 8:15 am 05/3/2010

    Interesting speculation, and what’s more: it’s accessible to a middlebrow layman such as myself.
    Good show!

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  3. 3. blf 8:15 am 05/3/2010

    I thought cats were the mice’s revenge for letting the Vogons blow up Earth Mark I.

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  4. 4. cass_m 8:37 am 05/3/2010

    If you refer to humans as their masters cats will never like you LOL With reference to pest control I would argue that cats are more important to humans, however, hunting was traditionally a male activity so this may explain why dogs were thought to be the more important of the domestic animals.

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  5. 5. Katharine 8:39 am 05/3/2010

    This is entirely in Romanian, but – Turn your cat into an electrical device!
    http://www.freegsm.ro/pisica/
    “Want to obtain an electric current from your cat?
    ElectrizeazaPisica.freegsm.ro (Electrified Cat).
    For starters, why does this site exist? To show you that there exists an innovative method to generate, with the help of cats, an electric current. Cat fur can liberate, through repetitive friction, electrons, which in combination with the induction of friction generates electromotor tension, therefore, indubitably, intensity and electric current.
    In the first place, we need a cat. You can use your own cat. The degree of electrification due to the fur may be smaller or bigger in the function of the cat. A Birman cat electrifies more easily than a no-name cat. Out of principle, light and humidity have an absolutely essential role in the electrified cat, being able to generate potentially 300% more electricity.”
    (obviously lulz)

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  6. 6. Lyle 8:54 am 05/3/2010

    #4 has it right the cats domesticated humans not the way we think about it. Today if the cat finds the right servant it has an easy life, of laying around sleeping and playing, in many respects easier than its servant. So cats are the smart ones and they tricked humans into becoming their servants.

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  7. 7. howard.peirce 9:14 am 05/3/2010

    It seems a bit odd to regard the “pest control” domestication scenario as speculative. Cats have only been widely kept as companion animals for a hundred years or so. For most of recorded history, and continuing in agricultural communities to the present day, cats were and are kept primarily for pest control.
    If domestication of cats is first found in the context of agriculture, and if cats have traditionally been associated with agricultural pest control, and if cats are still used for agricultural pest control, why is there any question about “why” they were domesticated? It’d be like arguing that just because people raise goats for milk and meat, there’s no reason to believe that goats were domesticated for milk and meat.
    If we can’t argue that cats were domesticated for pest control, then we can’t argue that any animal was domesticated for any reason, and we’re off into realms of philosophy, not science.

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  8. 8. Great American Satan 9:28 am 05/3/2010

    Well now, it’s interesting to see the comparison of cat and wolf levels of social dependence. Might be interesting to also see how baby humans and chimpanzees interact with adult humans they aren’t familiar with in similar tests.
    I think cats might be more neotenous than thought. Yes, they don’t have proportionally larger eyes than close wild cousins, but there’s more to neoteny than that. Like dogs, they breed all year. Like dogs, they have varied color. They probably had that before they were selected for it, meaning it probably came about for the same reason as in dogs – selection for the unrelated trait of a socially juvenile personality (wherein they view human benefactors the way they viewed their mothers when young).
    My cats act knead me (or the air near me) when being pet, in an instinct carried over from kittenhood (used to stimulate milk production for kitties, useless as adults). Other behaviors also suggest to me they have a kitteny, neotenous brain.
    I speculate Yes, they did domesticate themselves (following agrarian humans to feed on rodents), but over time they’ve been subject to the same influence as canines. Maybe they just aren’t all the way there yet.
    -

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  9. 9. Great American Satan 9:30 am 05/3/2010

    “My cats act knead me” should read “My cats knead me.” I shouldn’t post in the AM.

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  10. 10. Ron Shimek 9:49 am 05/3/2010

    Hi,
    You might take a look at:
    Driscoll, C. A., D. W. MacDonald, and S. J. Obrien. 2009. From wild animals to domestic pets, an evolutionary view of domestication. PNAS. 106: 9971-9978.
    The article is fascinating, but the last sentence of the abstract says it all: “Eurasian wildcats initiated domestication and their evolution to companion animals was initially a process of natural, rather than artificial, selection over time driven during their sympatry with forbear wildcats. ”
    Note: …cats initiated domestication…
    So, who domesticated whom? Cat owners have known for many years that humans were domesticated by cats to act as their servants. :-)
    On another minor side note, our family’s cats (from 2 to 4) over the years, have always been social, both with each other and us. It may depend on the breed, we tend to favor Maine Coon Cats, and they are known for their social nature with humans.

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  11. 11. Cassidy 10:31 am 05/3/2010

    @8
    I thought neotenous features were physical in nature. I don’t think a “kitteny brain” really counts, because an adult human is not going to instinctively respond to something like kneading (a kitten behavior, not a human one) the way he or she responds to big eyes.
    @4
    Dogs are considered more important to human society because of sexism? That seems like a bit of a stretch.

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  12. 12. Interrobang 11:05 am 05/3/2010

    And here I thought all this time I preferred cats to dogs because dogs are obsequious. It’s probably actually the neotony; if science ever figures out a way to make people like me think babies are cute (they look like they’re not done yet), people like me might start liking dogs more too.

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  13. 13. Cassidy 11:25 am 05/3/2010

    @12
    Don’t blame us scientists, it’s your own evolutionary failing ;)

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  14. 14. Jason G. Goldman 12:15 pm 05/3/2010

    @7: You may be correct – it may be apparently obvious that cats were domesticated as pest control. But just because something works a certain way now doesn’t mean it initially worked that way under different environmental conditions, and it also doesn’t mean it was explicitly selected for.
    As one example, I’ll refer you to the example of changes in coat coloration in domesticated foxes. This was not explicitly selected for – it came about as a side effect of selection for tameness, since adrenaline and melanin share a biochemical pathway.
    Another example: though human language has a similar function to animal communication, it doesn’t actually seem to emerge from the same mental or neural systems that subserve animal communication. Instead, the hallmark of language is its feature of recombination – taking a finite set of elements and being able to recombine them in infinite ways to construct meaning. The recursive mechanism that supports language evolved for whatever reason – and seems to have been co-opted and used for communication in humans.
    Before I start another blog post here in the comments, I just want to repeat the point: just because something works a certain way now doesn’t mean that earlier, under different environmental conditions, it worked the same way. And just because something is a certain way now, doesn’t mean it was explicitly selected for (or against).

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  15. 15. darwinsdog 12:17 pm 05/3/2010

    Cats aren’t domesticated. They’re Afro-Asiatic wildcats that have colonized a novel trophic niche, plain & simple.

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  16. 16. Great American Satan 1:19 pm 05/3/2010

    @11, “neotenous features were physical in nature” ? The brain is a physical structure. Most domestic cat behavior is instinctive rather than learned, so I take the juvenile behaviors as juvenile brain structure. In dogs, we see that they have a kind of arrested development where they don’t gain all the behaviors of adult wolves. I’m no expert, but I assume cats acting like kittens is a similar mental stunting.
    But I am starting to see a mistake in my thinking. The experimental russian foxes were bred for domesticity, which resulted in reduced adrenalin and morphological differences. I’d contend domestic cats display those features. But those characteristics aren’t the same as neoteny and I was conflating the two. I’m no genius.

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  17. 17. Pierce R. Butler 1:24 pm 05/3/2010

    I feed a small “colony” (I’m sure they think of themselves as a “pride”) of feral housecats near my house. (Yes, I’ve contrived to get them all spayed.)
    All are descended from the same matriarch (not counting the matriarch herself), and I’m pretty sure most have the same daddy. Out of the whole eight-pack, after years of consistent feeding, only three are friendly; just one will consistently volunteer herself to be stroked, and that only by me (and even she goes awol for days at a time). All hide from the presence of strange humans (even though all have learned to disregard the aggressive barking of my dog on the other side of a fence).
    I find it very hard to imagine that a similar clan of dogs, only one or two generations removed from domesticated-pet status, would be as wild and human-averse. Human selection has clearly been more effective with canids: I’m sure farmers and hunters pored carefully over each litter to pick the “keepers”, while cats were tolerated, or not, with much less regard for individual characteristics.

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  18. 18. Great American Satan 1:31 pm 05/3/2010

    @11 again – Actually, the wikipedia page on neoteny is a bit confusing. It starts off emphasizing physical appearance of animals, then goes on to mention more internal things such as larval insects that are sexually mature or lactose tolerance in humans.
    I first learned of the term with regards to the axolotl, a baby-faced variety of tiger salamander.

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  19. 19. Jason G. Goldman 2:14 pm 05/3/2010

    @18: Not being an expert in neoteny, I imagine that there are other things – e.g. mating cycle, sexual maturity, etc – that are unintended correlated byproducts of selection for overt physical appearance i.e. neoteny.
    @16: Yes, the brain is a physical structure, but I think what Cassidy (@11) is referring to is more properly called morphology – the overt observable characteristics. Things like big heads and wide eyes and distinctive coloration and whatnot. Also, you have to be careful when making claims like “most cat behavior is innate, not learned.” Something can be learned through experience without explicit teaching, training, or instruction. In humans, for example, we learn the sounds of our native language by experience, but this happens without any explicit intervention by the parents or anyone else.
    Also, equal care has to be taken when inferring that dogs are under-developed wolves. Dogs actually surpass wolves in many respects, and wolves surpass dogs in others. They don’t “fail to gain” some set of wolf-like behaviors, because the end goal is not to produce an adult wolf, it’s to produce an adult dog. You wouldn’t say (I hope) that chimpanzees are under-developed humans, after all. For as many years as dogs have been evolving (naturally and artificially), the wolves have continued to evolve too. The wolves of today are not exactly the ancestors of our pet dogs – instead, both share a common ancestor. We can refer to wolves as dogs’ ancestors, just as we refer to chimpanzees and gorillas as human ancestors, but its actually a bit more complicated.

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  20. 20. darwinsdog 5:51 pm 05/3/2010

    You wouldn’t say (I hope) that chimpanzees are under-developed humans, after all.

    No, I’d say that humans are “under-developed” chimpanzees.

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  21. 21. Birger Johansson 7:08 pm 05/3/2010

    Cats practically domesticated themselves; they simply followed the food as rodents would have been plentiful nearby the first granaries. And once humans noted cats carrying around “trophies” from their hunting grounds, it would have been a no-brainer to decide to leave the cats alone instead of killing them for food.
    An additional point in favor of cats (and other small feline species) as compared to dogs is that -to avoid conflicts with dominant cats who use excrement and urine as domain markers- they try to bury their urine and feces, a trait that to my knowledge is unique to small felines. This makes cats much easier to get along with than dogs, goats, chicken and other domesticated animals who literally shared the huts with the first farmers.

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  22. 22. Cassidy 7:16 pm 05/3/2010

    Morphology, yes! Sorry, it’s been a trying weekend here in Nashville, my clarity wasn’t up to par. I wasn’t trying to imply that behavioral characteristics don’t come from a physical source!
    What I meant was, while I can certainly see something being properly described as neotenous behavior (like kneading), what we think of as the neotenous traits that human adults find human baby-like and instinctively want to nurture and protect are morphological in nature, as Jason described, and seem to be found to a much larger degree in adult dogs, rather than adult cats.

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  23. 23. Lindsay R 7:42 pm 05/3/2010

    It seems to me that the ancestors of the domesticated cat already had baby-like features. Relative to dogs and alot of other animals cats have big eyes, round faces, and only slightly protruding noses. Whether that counts as neotenous, I don’t know.
    Another thought that struck me is that cats aloofness might have aided them in becoming our companions. Humans are natrually inquiaitive. We are after all the ones that struck out of the forest. I can’t help noticing that when a cat comes sluething around, I try to pet him, and he runs away that I only want to pet the cat even more. When he does finally come around, I’m much more happy to be graced with his presence than that of an overly friendly dog. Could it be that our ancestors saw these elusive creatures flitting in and out of the shadows and out of curiosity, left bits of food out to attract them? That their pest control abilities came into play later?

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  24. 24. monado 2:40 am 05/4/2010

    I think it’s pretty clear that when people started to keep grain against future need, the grain attracted rodents and the rodents attracted cats. Eventually, the humans and cats got used to each other. I believe that cats are commensals, ‘eating at the same table,’ rather than domesticated in the same sense as other animals.
    Once everyone had enough cats, excess kittens were likely to be drowned at birth to keep them from overrunning the household with starving, inbred cats. A kitten of unusual color was more likely to be kept, so novelty was a survival advantage as long as fewer than 10% of cats were that color. (I read that in Scientific American, ages ago.)
    Unlike most domestic animals, cats have roamed and bred freely until about 200 years ago, when people who noticed the variation in cats had the leisure to keep them caged and control their mating to maintain and eventually produce breeds.
    Cats were recognized as important rodent killers. A cat was allowed to roam freely according to English Common Law: otherwise it could not fulfil its function. There was a fine for killing a cat (before the witch hunts and their anti-cat prejudice). British ships had a position of Ship’s Cat on the roster, with a small allowance for its food. Just about every barn still has its family of half-wild cats. So I’d say that the pest-control function is basic.
    Rat-killing takes courage. Some cats regard it as a paying hobby and kill the occasional rat or mouse to eat. Some stick to mice. Others have been famous for killing several rats each night and leaving them where they could be admired. Kittens of a good ratter were prized because she would teach them how to hunt.
    Cats that are socialized and handled as kittens and fed as adults remain kittenlike to their humans throughout their lifetime. However, meet them outside and you encounter a much more adult personality, warier and focused on cat business. The secret of their success is that they can return to their childlike, trusting state for us and then go back to being semi-wild, specialized predators.

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  25. 25. monado 3:08 am 05/4/2010

    Of course, domestication could have happened differently. I’ll offer another scenario: kittens are incredibly amusing and baby-cute–probably the best entertainment before television. If there was a nearby lair of cats attracted by the rodents around a human settlement at the beginnings of agriculture, Momcat might have remained wary, but there would be a more-or-less constant supply of half-grown cats being playful. When the cats were more accustomed to humans, there would be kittens bopping around, tripping over things, attacking plants, climbing, and fearlessly chewing on proffered fingers. Kitten chases a butterfly–human throws a leaf. Kitten races in circles to catch it–human drags a stem of grass past the kitten. Kitten grabs at it frantically with starfish paws. Human throws a scrap of meat. Kitten devours it after somersaulting over it. Human throws another scrap. Gradually, humans take on the role of lifelong tidbit provider and substitute parent. Cat sleeps where it’s warm, gets up and kills rodent pests, puts up with human babies pulling its tail, and all is well.

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  26. 26. Old Baleine 9:50 am 05/4/2010

    You’ve got it exactly backwards- it’s not the cats who display a “relatively poor ability to socially engage with humans”; it’s more often humans who do not know how to socially engage with cats. The domestic feline is the only domesticated animal I can think of who has adapted itself to live among humans yet still remains essentially wild and independent. Nearly all dogs depend on their human owners to define the dogs’ identity. Cats do not. In the cat’s world, the cat is first, so if you wish to “socially engage” with a cat, you must do so on the cat’s terms, not your own.
    And if you are accepted by the cat, she may bring you presents.

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  27. 27. kimberly mccarthy 2:57 pm 05/4/2010

    Kim, This is it. The best description of the difference between cats and dogs you will ever find, brought to you through the compliments of your adoring father-in-law BT

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  28. 28. J. Maller 3:04 pm 05/4/2010

    Dear J and D, This is the best description of the difference between dogs and cats you will ever find.Hope you like it. Tom

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  29. 29. M. Singer 8:39 am 05/5/2010

    So, several hours on the ‘net led this writer to conclude that cats were domesticated because they killed pests – something I learned in eighth-grade Geography class in 1973. I’d like back the five minutes I wasted reading this, please.

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  30. 30. Jason G. Goldman 12:36 pm 05/5/2010

    @29:

    So, several hours on the ‘net led this writer to conclude that cats were domesticated because they killed pests – something I learned in eighth-grade Geography class in 1973.

    The interesting thing isn’t that cats killed pests. The interesting thing is why the domestication process has resulted in such apparent differences between cats and all other domesticated animals more generally, and specifically between dogs and cats when considering them as companion animals.

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  31. 31. Aylons 2:34 am 05/7/2010

    @29 The guy writes a wonderful lesson about domestication abd breeding, he references researches, and so on, and all you can read is “cats were pest killers”?
    Man, you don’t need your 5 minutes back. You need your whole schooltime back.

    Link to this

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