Science: History of Cats
Monday, March 17, 2008; 1:00 PM
Washington Post science writer Rob Stein and Monika J. Lipinski, a researcher from the University of California, Davis, School of Veterinary Medicine, were online Monday, March 17 at 1 p.m. ET to discuss findings from a study of cats' genes, including which breeds are most closely related and where they most likely originated.
The transcript follows.
Rob Stein: Hello everyone. Thanks so much for joining today's discussion about cats. And thanks very much to Monika Lipinski of the University of California at Davis for joining us. She played a big part in this new genetic study of our feline friends. I see there are already lots of questions already. So let's get going.
Washington, D.C.: I hope the study didn't involve the vivisection of these marvelous, intelligent creatures.
Rob Stein: No vivisection was involved in this research. It was a genetic analysis of samples the researchers obtained by swabbing into the animals' mouths.
Palm Beach Gardens, Fla.: I recently saw a Bengal cat at a cat show which had amazing coloring like a leopard (not a Bengal tiger) .... what is the origin of this variety?
Monika J. Lipinski: The bengal cat is a cross of a domestic cat with an Asian Leopard Cat. The cats in the shows are many generations removed from the original cross with the wildcat, therefore are mostly domestic cat but retain the exotic coat color.
Long Beach, Calif.: We own two Cornish Rex cats. As a relatively new breed, from a genetic mutation post-1950, are they likely to have less variety among their genes than other breeds?
Monika J. Lipinski: The genetic diversity largely depends on how large the original gene pool was and what kind of out-crossing is allowed and practiced. We are currently extending our investigation to include the Cornish Rex.
Christiansburg, Va.: Please discuss the physiology of purring and its purposes. Thanks--
Rob Stein: Unfortunately, this research only dealt with the genetic relationships and origins of various breeds and didn't get into anatomical analysis.
Woodbridge, Va.: Why are cats tame? And how closely related are they to small wild cat species such as the bobcat, lynx, etc.?
Monika J. Lipinski: Cats are tame because ancient humans chose the tame animals and allowed them to coexist in our settlements. Also, the tamer animals were more likely to approach human camps in the first place. Domestic cats are not closely related to bobcats or lynx; their closest relatives are the wildcats (Felis silvestris species).
Washington, D.C.: According to the study, how closely related are Maine Coons and Norwegian Forest cats? The belief that Maine Coons are descended from Norwegian Forest cats is obviously more believable than the raccoon theory, but I would be interested in finding out whether there is any truth in the supposed Viking link. Thanks!
Monika J. Lipinski: The Maine Coons and Norwegian Forest Cats are two distinct breeds. They are both of European decent, however. With the data we have, we cannot confirm or deny the Viking link.
Citrus Heights, Calif.: Siamese seem a bit different from other cats so what breeds are they closest to and where did they actually originate. What wild cats are they closest to?
Monika J. Lipinski: Siamese are definitely distinct. They are most closely related to the other Southeast Asian breeds such as the Havana Brown, Burmese, etc. In general, the cats from Asia are very distinct genetically from the rest of the cat world.
Mancos, Colo.: Thanks for the fascinating work! I was wondering if there are any thoughts on what the origins of domesticated cats were, meaning, where did the first cats come from, what kind of a species was it? I was also wondering if there were any thoughts on when and how the first domesticated cats came to the Americas? Thanks!
Rob Stein: Researchers believe cats were domesticated some 10,000 years ago. This and some earlier research suggest that probably occurred in a part of the world known as the Fertile Crescent. That's where agriculture began, and researchers think cats probably started living close to humans to hunt the rodents that fed on stored grain.
D.C.: Just a question about black cats actually... my Grandpa had the greatest cat for 15 years who was black and named Sun. When I was in the 8th grade I adopted a black cat from the SPCA named Jamie and he still keeps my Mom company to this day. My husband and I recently adopted a 1-year-old black kitty Dora and she is the the most personable adorable loving cat. My question is... why is there such a stigma around black cats? All I have ever known have had the best personalities and have been the cleanest and smartest animals. I realize some think they're unlucky, but from other skiddish cats I have seen and visited, the black ones always seem to be the most personable. Maybe they realize they have to make up for being black?
Rob Stein: There's lot of legend and folklore associated with black cats. They're not considered a breed per se. It's thought being black helps them hunt at night. While in our culture they're thought of as bad omens, other cultures see them as good omens.
St. Andrews, NB, Canada: Did the research give insight into:
1. the relationship between Maine Coon and Norwegian Forest cats?
2. Why the great genetic diversity in Maine Coons?
3. Any guesses on how long Maine Coons have been in North America?
Monika J. Lipinski: We can tell that both Maine Coons and Norwegian Forest Cats are of European origins, but can't resolve any closer relationship. The large genetic diversity is likely the result of a large initial gene pool and perhaps good breeding practices. Our data can't accurately date the age of the Maine Coon breed and the breed history is likely a better estimation.
Arlington, Va.: Hi - I brought three "alley" cats back from Kabul, Afghanistan, this past year. Two have body types similar to Siamese - one is tabby and other is calico. The third is short and blocky body and fur is short, very dense and krinkled. Markings are sort of tabby but more spots and color is similar to a lion cub. I have never seen another cat quite like her except in the colony she came from. If you would like blood samples and/or pictures for your study please let me know.
Monika J. Lipinski: Sure, we are always welcoming new samples, especially interesting and unique ones. You can look up our website on the UC Davis site for instructions on how to mail DNA samples.
Pittsburgh: Like with dogs, isn't there more risk of genetically-based problems associated with in-breeding, compared to (ahem!) mixed-breed cats? I like to think of my rescued companion cats as possessing "hybrid vigor," and they seem in general to have longer life expectancy, and fewer health and personality problems.
Rob Stein: Yes, that's right. The more inbred animals get the more likely they are to develop health problems. Cats, even fancy cats, are much less inbred generally than dogs. That's because cat breeds haven't been around as long and there's less inbreeding even with cat breeds than with dog breeds.
Frederick, Md.: How much has the look and general makeup of the cat changed since those early years? and what about coloration, have the tabbies, calicos and tuxedo type cats always been around?
Monika J. Lipinski: We are not sure how the ancient cats looked exactly. We are pursuing research in that area. The different coat color mutations likely arose as humans were breeding cats but the timing of the emergence of these different coat colors has not been determined.
Baltimore, Md.: Can you explain (in layman's terms) how you determined that the earliest domesticated cats came from Turkey?
Rob Stein: This group of researchers based that conclusion on the fact that the genes of cats from Turkey had the most diversity of all the cats they studied. An animal's DNA becomes more diverse the longer it's around because it's had more time to accumulate changes. So that makes them think the cats in Turkey have been around a very long time.
Woodbridge, Va.: Are cats really domesticated? My tabby acts just like an African lion. I think they put up with humans because we provide them food and shelter and clean up their litter box. If house cats weighed 200 lbs, we'd be in big trouble.
Monika J. Lipinski: That is one of the points discussed in the publication - the variable amount of "domestication" among cats. Some seem to cohabit with humans in a sort of symbiotic relationship while others, especially the purebred animals, are more dependent on our care.
Harrisburg, Pa.: I have a multi-feline household where the clowder has developed its own hierarchy. Positions of dominance or submission do not vary much, but I am concerned about what I can do to ease the stress of the one or two cats who are "shunned" by the rest of the clowder. While segregation of the weaker cats has worked in the past, it is not an ideal solution for either the human inhabitants or the feline ones. I would like to know if there is a way to assist the weaker felines in asserting themselves. Or, is this a hopeless cause?
Monika J. Lipinski: If you are really concerned about the dynamics in your household, you need to consult an animal behavioral specialist. I am a geneticist and therefore not qualified to give you an answer.
Washington, D.C.: Breeders often say they breed not only for looks but for personality. My British Shorthair is supposed to be laid back and reserved, but instead, he's a silly clown and all over everyone. So, is it really possible to breed for personality?
Rob Stein: One of the differences between dog and cat breeds is that dogs tend to be bred for their behaviorial characteristics -- hunting skills, herding abilities etc etc. Cats tend to be bred for their appearance. So I would think that personality type could certainly be selected for, to some degree at least.
Germantown, Md.: What are your thoughts about the project that involves breeding a domestic cat and an ocelot to produce an "ocicat"?
Monika J. Lipinski: Ocicat is entirely a domestic cat, not the result of a cross with a wildcat. It has simply been selected to look like a wildcat.
Virginia: Can you provide a link to your study? Usually there is a post for an associated article, but I can't seem to find one. Thanks!
washingtonpost.com: On the Trail of the Cat, Scientists Find Surprises
Rob Stein: Both a PDF of the study and a link are posted with the story. If you open the story on the website and scroll down to the bottom of the page you'll seem them under "Related."
Reston, Va.: Are Birmans really from Burma? There seems to be a number of legends and mystery surrounding the origin of the breed?
Monika J. Lipinski: With our data we can't zero in on a specific country, but we can tell that Birman cats are of Southeast Asian descent.
Bowie: On an off-but-related topic, should most dog breeds exist?
Dogs have been the subject of a lot of genetic experimentation, much of it way before people even understood genes, and has produced (according to some people) a number of inherently unhealthy breeds.
Are there some dog breeds that should just be discontinued?
Rob Stein: Well, I don't know if they should be discontinued. But it's certainly the case that some breeds have developed a lot of health problems because of inbreeding.
Falls Church, Va.: Wondered if you could comment on the possibility of using genetic manipulation to develop a hypo-allergenic cat. Is this a realistic goal?
Monika J. Lipinski: Work is being done on investigating the gene causing most cat allergies. Some breeds, such as Siberian, are naturally less allergenic.
Tabbies?: When I was in high school, I got my first cat and not knowing anything at all about cats, asked our vet "what kind of cat is this?" He snidely remarked "American Domestic" and started laughing. So I did my own research and found out my cat was a tabby. Yes, a very common type of cat, I know. Are tabbies considered a "distinct breed?"
Rob Stein: Tabbies are not considered a breed. The terms refers to the pattern of markings.
Boston, Mass.: Have you done any work on genetic markers for temperament? Everyone's heard of the temperamental Siamese, the placid Persian; I once had a vet tell me that striped tabbies have a good temperament. Is any of this true, do you think?
Monika J. Lipinski: I definitely think that there are unique behavioral/temperamental traits among the different breeds of cats. Behavioral traits are complex and often involve many interacting genes, making them difficult to pinpoint. With our genetic advances however, we are beginning to investigate these complex traits.
richmond, va: what about the hairless cat? was that a mutation that was then breeded? or are they really from outerspace?
Rob Stein: Here's what the the Cat Fanciers' Association says about hairless cats (http:/
In 1966 a domestic cat gave birth to a hairless kitten in Toronto, Canada. It was discovered to be a natural mutation and the Sphynx cat, as we know it today, came into existence. This cat and a few other naturally hairless cats have been found worldwide. These have magically been produced by Mother Nature and are the foundation for this unusual breed. Cat breeders in Europe and North America have bred the Sphynx to normal coated cats and then back to hairless for more than thirty years. The purpose of these selective breedings was to create a genetically sound cat with a large gene pool and hybrid vigor. This is a very robust breed with few health or genetic problems. The Sphynx is not always totally hairless; there can be a fine down on the body, which makes thecat feel like a warm peach.
Cat - Fairfax: How do cats' ability to bear very different young in one litter affect genetic analysis? My parents cat is a grey/black tiger, but his litter mate was a yellow tabby. . .
Monika J. Lipinski: The wonderful thing about cats is that most of the visible variation is caused by a handful of genes. In analyses such as the ones we perform we look at the whole genome and these few coat color genes do not affect our results.
Germantown, Md.: Did the study focus on Mitochondrial DNA or some other genetic marker?
Do you have any time estimates for the origins of the regional cat "clans" (Asian, E. African, European, Mediterranean)?
Monika J. Lipinski: The study used nuclear DNA, specifically neutral microsatellite markers. Microsatellites mutate too quickly to provide a solid estimate of divergence time, but are an excellent method for determining the relationship among closely related populations.
Washington, D.C.: can you please discuss the genetic origin of the tabby cat, and address how genetically diverse their DNA is? we have two, and i absolutely love tabbies. they're extremely social, and their markings are beautiful.
Rob Stein: Sorry to say that tabbies are not considered an official breed.
Warrenton, Va.: Is there any way to determine a link between genetics and behavior? I guess we can assume that the friendliest, bravest cats were the ones who chose to live with humans. Is there any genetic expression for this behavior? Are feral cats or wild cats markedly different genetically?
Monika J. Lipinski: There is definitely a link between genetics and behavior, but it is often a very complex relationship that involves many genes as well as environmental factors. We are beginning to investigate behavioral traits. Domestic cats are genetically distinct from wildcats, but can and do interbreed.
St. Andrews, NB: Is this most recent research published? If so, can you provide the reference for follow-up?
Rob Stein: Yes, this paper was published in the January issue of the journal Genomics, along with a similar paper. Both of them are posted on our website with the story.
College Park, Md.: While I have qualms about making more purebred cats or dogs, given the overpopulation of mixed breeds, I wonder why no one has developed giant or miniature cat breeds the way we've developed such enormous size variations in dogs?
I'm thinking a domestic cat that was 25 lbs., or conversely 3 lbs. full grown would be neat. Ethically speaking, I probably would never buy one, but still...
Rob Stein: Hmmm... Interesting question... Can't say I've heard of anyone trying to do that. But nothing would surprise me.
Silver Spring, Md.: A Singapura I would expect to not have much diversity since that breed developed from 3 particular cats in the 1970s. But how is "diversity" measured? Is there any diversity developed randomly through two cats of the same breed mating (I mean supposing they don't have the same parents, grandparents,... for so many generations)?
Also, how about a mutt cat. I have two sister cats - born 5 years ago today actually. They were born from a feral cat, from a litter of 5. But I'm not sure if they have the same father; different body types (only 1 of the litter, which I adopted, looked anything like the mom). How much more diversity do they have given they are not a particular breed? I guess I'm wondering how much cross-breeding is necessary (generation-wise) to maximize diversity?
Monika J. Lipinski: Diversity is lost through time in a closed gene pool due to many random factors, such as a cat never having an opportunity to reproduce and therefore not passing on its genes. Genetic variation can arise through mutation, but at a very slow rate. Therefore, as small, closed gene pool is more likely to lose diversity than to gain it. This is true for both breeds and for small, isolated populations of wild animals.
Eye Color: I have an all-white cat with green eyes, and my neighbor has an all-white cat with blue eyes. Are they the same "breed?" Are white cats any breed at all?
Monika J. Lipinski: No, white cats are not a specific breed, they are a coat color variation. This is exemplified by the fact that many breeds have white cats.
Ashburn, Va.: I've heard that white hair is one of the marks of domestication in animals. Is this true for cats? Do wildcats ever have white fur?
Monika J. Lipinski: White hair would make a cat in the wild more visible in the forest setting, therefore making it harder for him to hunt. To my knowledge, wildcats do not have any white markings.
Rob Stein: Thanks so much everyone for such great questions. I know you have a lot more, but unfortunately our hour is up. I'd like to thank Monika Lipkinski again for helping out with this fascinating discussion. We're looking forward to the next installment of your research.
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