Science: Cats Domesticated Themselves
Friday, June 29, 2007; 1:00 PM
A genetic study of the origins of the domestic cat, being published today in the journal Science, indicates that tabbies, Persians and Siamese cats wandered into Near Eastern settlements at the dawn of agriculture -- about 12,000 years ago, actually. And their mission was food, not friendship.
Read the Story:
Washington Post staff writer David Brown and Carlos A. Driscoll, research scientist at the University of Oxford, will be online Friday, June 29, at 1 p.m. ET to discuss the findings.
A transcript follows.
David Brown: Good afternoon readers and cat-lovers (at least mostly, I assume). We are lucky to have this afternoon the chief researcher of the fascinating study on cat domestication, Carlos Driscoll. He is with us from the National Cancer Society lab in Frederck, Md. We'll start answering your questions in a minute or two.
Bowie, Md.: Thanks for the article, it was a great insight into my cats' basic behavior, well after thinking about this how were cats considered gods in some times and considered creatures of satan at other times in human history?
David Brown: I was told when doing this reporting that the idea that cats are the companions of witches and other dark forces arose because in early Christian times it was known that they were worshipped in some pre-Christian cultures, notably Egypt. But whether that is the reason for that association, I don't know.
Rockville, Md.: I've heard conflicting accounts of the origin of the British Shorthair breed of domestic cat. Is it true that the breed decends from cats of Rome that accompanied Roman soldiers on their conquest of modern-day Britain? If so, where do they get their incredible coats of fur -- really the best fur ever.
Carlos A. Driscoll: it seems that cats were first brought to Britain by the Romans by about 10 AD, only a few years after they arrived. the route cats took is unclear- they may have followed Roman troops across France (Gaul) or they may have come directly by boat on supply ships, or both. This is something I will be looking into with colleagues at the University of Durham in England. however, the direct connection between these first British cats and the specific breed is unclear. there was a Scientific American article by Neil Todd you might be interested in.
Durango, Colo.:"I am the cat who walks by himself and all places are alike to me." Rudyard Kipling, "The Just So Stories"
David Brown: As anyone who has read the "Just So Stories" to a child in the last few decades knows, they could do with a little updating and political-correction. But in some things they are right on. Kipling knew his cats.
I knew it!: I even have a magnet on my fridge that says "It's my cat's world, I merely open the cans."
One of my cats would not pay any attention to my husband until two years into our marriage, when he took over opening the morning can of cat food.
David Brown: In my experience, there are cats that are obsessed with food and can do little else than angle for ways to get it, while others have other things on the agenda, like lying in the sun or occasionally climbing a tree.
Dayton, Ohio: Reading the article, would it be fair to say that domesticated cats were part of an agricultural "package" that got transferred from one culture to another?
Carlos A. Driscoll: That does seem to be the case for cats and is the case for mice. However we will need to follow the trail of the cats by looking at their remains, which we do plan to do. New 'ancient' DNA techniques will hopefully allow us to look at remains from the neolithic through to today. If 'near eastern' cats seem to be associated with agricultural settlements in Europe it would prove the case.
Fortaleza: Anyone who has lived with cats would likely respond to the story that cats came to people out of mercenary reasons with a DUH, NO KIDDING. We domesticated cats? Maybe cats domesticated us. My favorite cartoon on the topic showed a dog getting fed and saying his owner gave him everything he needed -- she must be a god. Next panel showed a cat speculating that his owner gave him everything he needed -- HE must be a god. I love cats, but they are independent and selfish. Like us.
David Brown: It seems likely that at least some of the obvious differences between cats and dogs reflect the traits they have in the wild that have been molded but not obliterated by domestication and breeding. Wolves live in packs, hunt cooperatively and have a strict social hierarchy. Wildcats are essentially solitary animals. This latter has changed considerably with domesticated cats, who not only tolerate other cats' presence, but will even at times feed together from the same source. Nevertheless, they retain their sense of solitariness and lack of supplicative, dog-like behavior.
Bethesda, Md.: I have always heard that the first evidence of domesticated cats dated back 9,500 years ago to a archeological find in Cyprus. Did you test cats on this island?
Carlos A. Driscoll: unfortunately, no, I didn't. it would be exciting to do so however because what we would expect to find is that cats there- even modern day feral cats- the 'resident' population, would look genetically like wild near eastern cats. There were no cats native to any of the Med islands, except Sicily. The going hypothesis is that cats were brought there very early on in in the domestication process by Phoenician traders and settlers directly from the Phoenician home around Lebanon (not from Egypt, as were British cats by Rome). That fact makes the island cats very interesting as they may represent a sort of 'proto-domestic cat'.
Gaithersburg, Md.: Why is it that in movies or cartoons about inter-species conflict, cats vs. dogs, cats vs. mice or cats vs. birds, the cats are always the bad guys?
Cats are just as good as dogs and much better than mice (for the human audiences of the media).
David Brown: I would hazard a guess that the reason is that cats have not lost any of their highly skilled and quite cold-blooded (or so it seems) predatory skills. And of course they sometimes play with their prey, which suggests evil intent. They may have become more friendly when they came in from the woods, but when they get down to business of hunting and killing they haven't lost a step in 10,000 years.
Capitol Hill, Washington, D.C.: I am a little concerned about some mistaken conclusions, at least I think they are mistaken, that could be drawn from your fascinating conclusion. Many people think that if you dump a housecat outside, it can hunt for itself and generally revert to living in the wild. My experience is that this is not true, that once cats are that domesticated, they will need our opposable thumbs forever. They would die if deprived of human care. Your comments? Thanks!
Carlos A. Driscoll: there will clearly be some attrition should cats 'go feral', however, there is plenty of survival instinct and capability in cats and many would survive. remember that there are about as many feral cats in the US as there are house pet cats, though the lifespan of a feral cat is much shorter.
A good indication of this was an individual cat I found in the western Gobi of Mongolia. I was there in April (read: just after a long winter) and found a clearly domestic cat in perfectly good health that approached our camp and mewed. I didn't even have to trap it- I simply mewed back as I would to any of my own cats and got it closer and closer until it was eating out of a tin.
Washington, D.C.: Can the wild cats like the Scottish wild cats interbreed with domestic cats?
Carlos A. Driscoll: yes, they certainly can. And that is likely the major conservation issue for silvestris. Domestication is a very recent event in evolutionary terms and barriers to reproduction have not arisen. The continual admixture threatens wildcats in several ways; the most pressing concern is that hybrid cats are not protected under the law, they are treated like feral domestics, and rightly. But, should the entire population of wildcats become hybrid, to any degree, then the entire population might be lost. The biological danger is that gene complexes adapting wildcats to their environment might be destroyed by this admixture. wildcats might then, for example, become more and more 'domesticated' and themselves begin adapting to humans.
Washington, DC: Although, per the article, cats' main objective in becoming associated with humans was the related source of food, is it safe to say the relationship between humans and cats has evolved beyond that? (i.e., is my anthropomorphizing of my cats merely wishful thinking, or could there be some sentiment there beyond: Feed me!)
David Brown: It has evolved somewhat, I am sure, and it has also been altered by breeding. The few cats I have lived with have all been mongrels, but I am told that some breeds (Siamese I believe among them) absolutely hunger for human affection and companionship. My purely anecdotal experience is that cats that look like wildcats, i.e., have the classic mackeral-striped coloration, are a little more skittish and suspicious of strangers than many fancy breeds. Are they a bit more wild? I guess I would guess they are, but I may be wrong.
Germantown, Md.: Is the fact that all cats are descended from one common ancestor responsible for the fact that there is little variation in their size and basic features? As we all know, dogs vary considerably by breed, but cats do not. Their coats are different, sometimes their muzzles vary, but overall they look pretty much similar. (There probably won't be a "world's ugliest cat" competition any time soon.)
David Brown: I didn't have the space to get into this in the story, but the genetic evidence suggests that even though all domesticated cats are descended from the lybica subspecies of the Near East, there are five different matrilineal lines (as detected by mitochondrial DNA signatures), which means that there were at least that many domestication events there. So not quite one common ancestor. As to the different morphology of dogs and cats, I believe this is the result of more intensive breeding for use among dogs---to get big hunting dogs, fast dogs, digging dogs, lab dogs, etc., with that breeding going on for a long time. On the other hand, intensive cat breeding began in the 19th Century in England, and cats have never been bred for work.
Carlos A. Driscoll: that's right. cats were probably not selected for anything other than tameness itself, so there were few pressures on it's physiology. domestic cats HAVE changed slightly from their ancestors (gut length for example) but to nowhere near the degree of other domesticates.
'one common ancestor' in this case refers to a population of cats rather than an individual cat.
Annapolis, Md.: Stray cats are essentially vermin, consuming native species and spreading disease to domestic cats. What is being done to contain them?
Carlos A. Driscoll: not enough. As a cat lover myself I have no trouble at all saying that feral domestic cats should be reduced or elimanated from environments where they contact native wildlife. Feral cats consume an astounding number of birds, rodents and reptiles and even larger mammals like rabbits, pika and guinnea pigs. Spay and Neuter!
Los Angeles, Calif.: Great article. I have always owned cats as pets and I have always meowed back to them. Do they recognize that as some sort of conversation? I always get a reaction back when I meow. Thanks.
Carlos A. Driscoll: see my response regarding the mongolian cat!
Laurel, Md.: Although it may seem a little on the disgusting side to us today, most food that cats eat is something a human would also find beneficial, making cat-keeping infeasible in a food-short population, unless the cat could catch its own.
When in history did it become common for the average citizen to keep a cat?
Carlos A. Driscoll: keeping cats as pets dates from about 9500 years ago, as far as we know. the earliest record of what is plainly a domestic house cat is 1600BC in Egypt. However, the find from Cyprus mentioned above seems to indicate that cats were kept as pet even before they were truely domesticated.
Hansbeke, Belgium: Passionate cat lovers' distinctive psychological traits make it easier for them to bond with cats than people who pay less attention to cats. Since cats are keen as much, if not more, on love as on food cats choose their human companions if they can.
Would not the desire for understanding and kindness be a greater driving factor in cats relationships with people?
David Brown: There obviously is a range of cat personalities and a range of cat-owner personalities. Everything happens under a bell-curve (always the case in biology). That said, I think there is little doubt that "desire for understanding and kindness" is something more likely to be found in the dog-human relationship than in the cat-human one. An interesting study in Science on 22 Nov 2002 looked at "social cognition" in dogs. It showed that dogs have a greater skill in learning the location of hidden food from human communication than either wolves raised by human beings or chimpanzees. In other words, dogs are better at "reading" human beings than either their closest relatives (wolves) or our closest relatives (chimpanzees). This suggest that the ability to intuit human emotion and subtle directions is something that has evolved or been bred into domestic dogs.
Washington, D.C.: Does the cancer lab experiment on cats?
Carlos A. Driscoll: We use cats as part of our gene mapping study (ie. we breed them) but we do not use tham as experimental animals.
Howard County, Md.: Thanks for the chat! Did you gather any other infomation on the wild and domestic cats besides genetic information?
Carlos A. Driscoll: I have not. the cats are pretty elusive and I didn't have time to collar and track them myself- although that was what I had initially planned to do instead of living in a lab!
Arlington, Va.: We have a polydactyl tabby we believe is part Maine coon, and it is striking how similar he looks to the British wildcat Felis sylvestris sylvestris -- down to the white chin and stripe patterns on his forehead and raccoon-like bushy tail. When we were in Scotland we saw a postcard of a "Wildcat" and couldn't get over how it looked exactly like our pet. He and his sister have the best personalities - they follow you around everywhere like dogs, and constantly play and clown around.
David Brown: I agree. I think one of the more remarkable things about this subject is how little the morphology has changed between the wildcat progenitor and its domesticated descendants. Personality and behavior change, yes, but many many cats I have known are indistinguishable from the pictures of the Scottish wildcat.
Raleigh, N.C.: On the subject of cats varying less than dogs -- As Darwin pointed out in The Origin of Species, this is likely because selecting cat traits by breeding is far more difficult than with dogs. Cats can't be leashed or penned easily, but dogs can. So breeding distinct lines has been more practical in the case of dogs, and as a result dogs display greater variation in size, shape, and so on. (Darwin makes a clearer argument than I can -- this is only my summary and recollection).
Carlos A. Driscoll: that is largely correct. Darwin noted in his book on plants and animals under domesticaton that England did not have it's own breed of cats. and that because they were difficult to keep indoors. Every night, bring in the dog and throw out the cat. so they bred freely ( they were a panmictic population).
however, when people set their mind to something they can achieve even the impossible and beginning about the same time Darwin was writing the English did begin developing breeds of cats. And in 1871 they held their first cat show at the Crystal Palace in London. In 1887 the first cat club was formed there.
So artificial selection in cats has only been going on in the west for about 200 years- no time at all really. As more and more people select harder and harder for interesting (depending..) traits, we will begin to see more and more variation. Munchkin cats, for example, is the recent capture of achondroplasia in domestic cats. Dogs have had the trait for years.
Santa Cruz, Calif.: How about that purr? It seems that domestic cats purr from pleasure, but I understand for wild cats it's a sign of stress, or an impending pounce. I can never quite tell where it is coming from, either. The throat? The diaphragm?
Carlos A. Driscoll: Purring occurs in cats with a hyiod bone, and this is only the smaller cats, particularly the genus Felis. this bone is in the throat of cats, just as it is in humans, and helps to support the tongue.
all purring cats seem to do so when contented. larger cats, those that roar, cannot purr as their hyiod is fused.
Charlottesville, Va.: Interesting topic! Where do Asian Leopard cats (indigenous to Indonesia and Taiwan) fit in? These are the cats that are the foundation of the Bengal breed (along with domestic cats, obviously).
I have two Bengals, and despite the suspicion from some quarters, I have observed very little difference between the so-called "hybrid" cats and plain ol' domestic cats. Your research seems to indicate that the observations of the people familiar with these breeds is true: there isn't that much difference. Certainly not as much as you see with hybrid wolf-dogs. The cats just don't seem to have the behavioral issues, but if they aren't that far removed from their wild ancestors to begin with, that would explain it.
The only thing specific that I have noticed is that my Bengals love to play in water and they have a weird yowl instead of a standard "mew". Other than that, just friendly, active, athletic cats.
Carlos A. Driscoll: the bengals that are available as pets are, at a minimum, five generations removed from the Asian leopard cat. So there is substantial selection against undesirable traits before they reach the popular market. We have bred a substantial number of crosses between ALC and domestics and I can tell you there is a huge difference if you have an F1 (first generation cross)! they are absolutely nuts! more like havinga dog than a cat and they eat just as much.
And we too have noticed the hybrid's love of water. I've had them swim out to my boat to see what I was doing.
David Brown: I think we are out of time. I want to thank Carlos Driscoll for taking time out from his research to do the heavy lifting on this chat. We all benefited from it.
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