Hard wired to the past
Felis silvestris lybica Photo by Noorderlicht
When you get right down to it, house cats are pretty useless. If you’re overrun with mice, cats can be a help, but that’s pretty much it. They are fiercely independent and, unlike dogs, which have a want-to-please-their-master nature, cats don’t really give a flip. They don’t fetch, they don’t roll over, they don’t sit up and beg, and, for the most part, they don’t come when called. If you had a kid who acted like a cat, you would probably put him/her up for adoption. So why are they the most popular house pet in the world today?
Scientists using DNA analysis have determined that virtually all house cats alive today are descended from a specific line of wild cats, Felis silvestris lybica, that are indigenous to the Middle East. Although there are a number of lines of wildcats throughout the world, mitochondrial DNA analysis of all breeds of house cats appears to indicate they all descended from this one branch of the wildcat family.
With the geography and an approximate age of the initial phases of cat domestication established, we could begin to revisit the old question of why cats and humans ever developed a special relationship. Cats in general are unlikely candidates for domestication. The ancestors of most domesticated animals lived in herds or packs with clear dominance hierarchies. (Humans unwittingly took advantage of this structure by supplanting the alpha individual, thus facilitating control of entire cohesive groups.) These herd animals were already accustomed to living cheek by jowl, so provided that food and shelter were plentiful, they adapted easily to confinement.
Cats, in contrast, are solitary hunters that defend their home ranges fiercely from other cats of the same sex (the pride-living lions are the exception to this rule). Moreover, whereas most domesticates feed on widely available plant foods, cats are obligate carnivores, meaning they have a limited ability to digest anything but meat—a far rarer menu item. In fact, they have lost the ability to taste sweet carbohydrates altogether. And as to utility to humans, let us just say cats do not take instruction well. Such attributes suggest that whereas other domesticates were recruited from the wild by humans who bred them for specific tasks, cats most likely chose to live among humans because of opportunities they found for themselves.
Turns out that the answer to the domestication question is that cats were useful to our ancestors for the same reason they are useful to use: their mousing ability. When humans turned to agriculture and started storing quantities of grain, rodents became a problem because they bred like flies and overran the human food supply. Cats, which don’t eat grain but do eat rodents, were the solution, so we hired them on despite their quirks.
So are today’s cats truly domesticated? Well, yes—but perhaps only just. Although they satisfy the criterion of tolerating people, most domestic cats are feral and do not rely on people to feed them or to find them mates. And whereas other domesticates, like dogs, look quite distinct from their wild ancestors, the average domestic cat largely retains the wild body plan. It does exhibit a few morphological differences, however—namely, slightly shorter legs, a smaller brain and, as Charles Darwin noted, a longer intestine, which may have been an adaptation to scavenging kitchen scraps.
Unlike dogs, which exhibit a huge range of sizes, shapes and temperaments, house cats are relatively homogeneous, differing mostly in the characteristics of their coats. The reason for the relative lack of variability in cats is simple: humans have long bred dogs to assist with particular tasks, such as hunting or sled pulling, but cats, which lack any inclination for performing most tasks that would be useful to humans, experienced no such selective breeding pressures.
As a little diversion let me demonstrate the difference between art and science. The article on the domestication of cats took up five pages of text in Scientific American. J.R.R. Tolkien (yes, he of Lord of the Rings fame) pretty much transmitted the same information in a short poem. I came across this poem in my youth and was mesmerized by it. I loved the rhyming pattern and was amazed that so much information could be compressed into what seemed to be just a little piece of doggerel.
Cat
The fat cat on the mat
may seem to dream
of nice mice that suffice
for him, or cream;
but he free, maybe,
walks in thought
unbowed, proud, where loud
roared and fought
his kin, lean and slim,
or deep in den
in the East feasted on beasts
and tender men.
The giant lion with iron
claw in paw,
and huge ruthless tooth
in gory jaw;
the pard dark-starred,
fleet upon feet,
that oft soft from aloft
leaps upon his meat
where woods loom in gloom –
far now they be,
fierce and free,
and tamed is he;
but fat cat on the mat
kept as a pet
he does not forget.
As I said, on the surface it appears to be a little nursery-type of poem, but it’s not really. The rhyme sequence is astonishingly complex for such a small poem. The odd lines rhyme at the end while the even lines each have three internal rhymes, and it’s all done in just a few words. Yet is conveys the essential nature of cats better than the long Scientific American article without seeming to stretch to make any of the rhymes work.
It’s hard to believe that Tolkien wrote such a gem intending to include it in The Lord of the Rings, but decided not to. It ended up being kind of a throw away.
We, ourselves, like cats, walked “in thought unbowed, proud, where loud roared and fought [our] kin, lean and slim, or deep in den in the East [and] feasted on beasts” in a time long past. And just like fat cats on mats everywhere, we remember, too, those “fierce and free” primal days, if not in our conscious brains, at least in our DNA. We are hardwired to gobble meat with “huge ruthless tooth in gory jaw.” If you don’t believe me, take a look at this YouTube of chimps, our nearest genetic ancestor hunting and eating meat.
Beware. And I’m not kidding. This video is not for the squeamish, so be forewarned.
I’m not nearly as clever with verse as J.R.R. Tolkien, so I won’t attempt to capture the feelings this video engenders with poetry. But it should be obvious from the watching what hunts must have been like in our own past. I suspect not too different than the one you just saw. And, friends, that is the primitive circuitry deep inside of us all; we differ from the chimps you saw by a mere 6 percent of genes. That means that we have 94 percent of our genes in common with them. Au contraire to what our vegetarian friends would have us believe, we have the GI tracts of carnivores, not herbivores, and we were designed by nature to use every last speck of the nutrients in meat. We can survive on all-meat diets just fine, whereas we can’t survive on an all-plant diet without supplementation.
We’ve developed our large brains and our social instincts as a consequence of meat eating. I’m planning a post on this subject in the near future, so you can see how our very humanness arose because we developed a taste for meat. We are carnivores to our very cores – were we not, we would still be roaming the savannas with brains the size of grapefruits.
We may sleep and dream of larger houses, bigger cars and vacations to exotic locations, but our insides still remember when we were “fleet upon feet” and leapt upon our meat “where woods loom in gloom.” It was this memory that drove Paleolithic Man, with whom we have 100 percent of genes in common, to hunt to extinction all the large beasts (whose skeletons fill natural history museums everywhere) to extinction from the Bering Strait to Tierra del Fuego in about 1000 years. They didn’t make this effort because they used meat as a condiment.
Whether we like it or not, we are hard wired to our past.
Photo of F.s lybica by Noorderlicht
H/T to Richard Nikoley for alerting me to the YouTube video
Any suggestions on increasing cholesterol levels? I had mine checked at the ‘health fair’ recently, and the total was 149. Hdl was 59 and Tri was <45 (so they didn't give me a LDL level). Of course they thought it was great, but I think (based on the charts in Protein Power) that its too low. I eat lots of grass fed beef, cook with lard, use butter and just a little olive oil here and there. I'm not "low carbing" persay currently though I do try to keep the carb intake down probably around 150g or so per day.
What is the best way, eating from the Paleo side of the food choices, to increase cholesterol levels?
I wouldn’t worry about it. If you are eating a Paleo diet, your cholesterol is probably right where it should be for you. I wouldn’t try to raise it.
Dr. Eades, the following is from a NY Times article on the anti-dementia effects of eating fish. But I’m wondering if you agree with the quote that red meat is bad for the brain?
“There is a gradient effect, so the more fish you eat, the less likely you are to get dementia,” said Dr. Emiliano Albanese, a clinical epidemiologist at King’s College London and the senior author of the study. “Exactly the opposite is true for meat,” he added. “The more meat you eat, the more likely you are to have dementia.” Other studies have shown that red meat in particular may be bad for the brain.
http://www.nytimes.com/2009/07/21/health/21fish.html?hpw
No, I don’t agree with the quote. The ‘other studies’ to which they refer are observational studies, which can’t prove causality.
off-topic… An interesting press release:
http://www.eurekalert.org/pub_releases/2009-07/jhmi-dpc072109.php
Doc, Have you seen more kidney stones in your low-carb patients over the years? I wonder if I need Potassium Citrate.
I’ve never had a patient develop a kidney stone that I know of on a low-carb diet. But, then again, I always put them on potassium supplementation.
Sorry for adding yet one more comment about cats and how unique and amazing they can be, but Vadim’s story about his mother and her cat reminded me of this.
At a nearby nursing home they have a cat that roams at will through the place. This cat has an uncanny sense for impending death. When it senses that someone is failing (well before the doctors or nurses are even aware), the cat will go into that person’s room and not leave. The cat will sleep on the bed and try to comfort the person, nudging the person’s hand, allowing the person to pet it for hours, and otherwise providing comfort to the dying person. And sure enough, the person passes within a day or two.
The nurses and doctors have seen this so many times, they now watch the cat and when it seems to be staying around one person, they give that person extra care and attention.
I know there will be cat-haters out there who will say the cat brings on death or bad luck or some such nonsense. I feel, as do the medical staff and patients and families, that the cat brings comfort and ease to the end of days.
Thank you Dr Eades for more great food for thought. I’ve been puzzling a lot over the topic of the human diet – carnivore or omnivore – that has been raised in the comments. I’m currently reading Richard Wrangham’s “Catching Fire” (which I believe you said you have in your reading stack, too) and recently came across some interesting commentary on this paper from Barry Grove’s site:
Popovich DG, et al. The Western Lowland Gorilla Diet Has Implications for the Health of Humans and Other Hominoids. J Nutr 1997; 127: 2000-2005
http://www.second-opinions.co.uk/should-all-animals-eat-a-high-fat-low-carb-diet.html
With the change in diet and development of a smaller gut in the transition from australopithecine > habilene > Homo erectus that Wrangham describes, our gut flora must have been significantly reduced. Unlike the western lowland gorilla, which subsists on a leafy diet, we don’t have a large hindgut where huge colonies of bacteria can ferment carbohydrates to produce short chain fatty acids that can then be absorbed by the body to be used for energy. Nonetheless, according to this study I came across today which reports comparative analyses of extant mammalian gut microbial communities, our gut microbiota seem to peg both us and the gorillas as omnivores.
Ley, et al. (2008) Evolution of mammals and their gut microbes. Science, 320(5883), 1647–1651.
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2649005#SD1
All of the above seem to track with Ungar et al.’s conclusions on early Homo’s ”dietary versatility” quite plausible:
“Craniodental adaptations and material culture would have allowed early Homo, and especially H. erectus, to eat a broader spectrum of foods than could earlier hominins. This does not mean that early Homo individuals had particularly varied diets, but rather that they may have been capable of eating a broader range of foods. Chimpanzees and gorillas show significant differences in their diets, depending on the individual population and the seasonal availability of resources within home ranges (e.g., Goodall & Groves 1977, Vedder 1984, Wrangham et al. 1991, Yamagiwa et al. 1992, Tutin et al. 1997, Yamakoshi 1998). Ethnographic studies over the past century have shown human foragers to have an even greater range of diets, from nearly all animal products (e.g.,Hoet al. 1972) to mostly wild plant parts (e.g., Gould 1980). This finding led Milton (2002) to argue vehemently against a single hypothetical “Paleolithic diet.”
Perhaps then, early Homo, and especially H. erectus, had an adaptive strategy of dietary versatility. This versatility would have been advantageous in an unpredictable, changing environment or an environment dominated by many different microhabitats. Perhaps H.
erectus was the first hominin to leave Africa because it was the first with sufficient dietary versatility to allow it to do so. It may be no coincidence that this species spread into habitats as far north as the Republic of Georgia, and perhaps as far east as Indonesia, so quickly following its origin and first appearance in Africa (Swisher et al. 1994, Gabunia et al. 2000).” (Ungar, Grine, & Teaford, 2006, pp. 220-221)
Ungar, P. S., Grine, F. E., & Teaford, M. F. (2006). Diet in early Homo: A review of the evidence and a new model of adaptive versatility. Annual Review of Anthropology, 35, 209-228
http://www.hopkinsmedicine.org/fae/PSUFEGMFT2006ARA.pdf
There are basically two types of digestive systems: one that is found in herbivores and one found in carnivores. The carnivore GI tract can digest plant foods and the herbivore digestive tract can digest animal foods (which is how mad cow disease was thought to have started). But, in keeping with their design, the carnivore GI tract does better with meat and the herbivore with foods of plant origin. Gorillas and pandas are carnivores that have adapted to vegetarian diets, but they end up having to make eating their life’s work to get enough calories to support their lives. I plan a long post on this subject as soon as I can get some consolidated quiet time to get it written.
Hi Dr Mike
Did you see this?
It reports on selectively breeding caterpillars on different protein-carb ratios so that:
“After as few as eight generations, individuals from the high-carbohydrate diet will be much less prone to store the excess carbs as fat. Conversely, those from the low-carb diet will be more prone to deposit carbs as fat.”
http://judson.blogs.nytimes.com/2009/07/14/coping-with-excess/
Desmondo
Yes, I saw it. I think we humans need a lot more than 8 generations to desensitize us to carbs. The ‘thrifty gene’ hypothesis was promulgated by James Neel a number of years ago, but now even he has backed away from the idea. A recent study actually did a genetic analysis looking for the ‘thrifty gene’ without finding it.
How long until statins are added to the water supply by law?
The Next Blockbuster Drugs – Newsweek, July 22, 2009
From cholesterol fighters to asthma relief, these treatments could earn Big Pharma $170 billion
“Cholesterol-lowering agents are arguably the top U.S. lifestyle drug. An American Journal of Medicine article in June suggested that Americans have worse health habits than they did 18 years ago. Waistlines are expanding. Physical activity has decreased, and so has healthy eating. It’s why doctors are apt to prescribe cholesterol-lowering drugs such as statins to patients as young as their late-20s. The drugs have been shown to cut cholesterol, and thereby reducing the risk of heart disease.
“In the future, even patients with normal cholesterol levels may be prescribed statins. An American Heart Association study in November showed that AstraZeneca’s statin Crestor dramatically cut deaths, heart attacks and strokes in patients that had fine cholesterol levels, but high levels of a heart disease-related protein.”
http://www.newsweek.com/id/207928
Here is my post on that study.
A friend of mine, after reading Taubes’s book, looked around for a catfood without many carbs for his diabetic cat that he has been giving insulin shots to for 5 years. He found one, it wasn’t easy, but now the cat has normal blood sugar (88), no longer takes insulin, and has lost a third of it’s weight. Not quite sure why the catfood industry thinks that cat’s require lots of carbs, except that protein is expensive and cats don’t have much money. Peter Silverman
Peter Silverman, I am quite certain than the cat food industry knows that cats are obligate carnivores and they actually understand what the term means. This aside, they are dedicated to the bottom line. And carbs are a potent source of income. More interesting, in what has to plumb new depths of conflict of interest, the same veterinarians who benefit from treating feline diabetes sell high carb cat food. Did these vets forget what they learned in veterinarian school about cats being obligate carnivores? Or, has some vested interest used sleight of hand to redefine the meaning of carnivore to mean protein and carbohydrate. Maybe both?
Of course we know treating disease is much more lucrative than reversing disease. So inject the animals with vaccines, give them antibiotics for any little thing. sell the owner “high quality” food, such as Science Diet or Iams, then treat the resulting chronic diseases.
Then when the disease is identified (a little late) as “diet-related,” move the animals onto a more specialized food that costs more and that only vets sell. It’s the perfect scam!
Excuse me for being cynical, but my cats don’t get vaccines and they eat raw meat and I avoid antibiotics whenever possible, and I can tell you most vets are VERY unfriendly to and unwilling to work with me. So I quit going to them.
By the way, I had a conversation with an out-of-work vet who told me the latest marketing model was when very ill animals are brought in the vets write up the most expensive, most comprehensive treatment plan. If the owner can’t afford it, then the vet recommends euthaniasia. This way the vet cultivates monied owners and cuts out all the riff-raff.
It’s a good thing physicians don’t follow that model with people.
To Peter Silverman, I think your last sentence hits the nail on the head about pet food.
Carbs are *cheap*. Same reason that so many poor folks stock up on carbs – cheap filler.
My cats and dogs all eat a grain-free, high-protein, low-carb diet, but I’m lucky enough to be able to afford to feed them at, as well as being able to afford grain-free, sugar-free, low-PUFA, low carb food for myself as well.
And two of my cats are sleek and skinny, but one – even on this diet – is still immensely fat. And my 5-year-old dog is battling an agressive cancer, even though I was sure his grain-free, low carb, high protein diet would be protective against it. And me? I can barely manage to keep my weight below 300 pounds despite strict adherence to all the low carb principals in the book.
But sometimes it works. For years I had one of my dogs on the stardard low-fat, high-carb “diet” food recommended by my vets because she was very overweight even though I was feeding her so little food that she was constantly ravenous. She weighed 52 pounds and I fed her less food than her 22-pound brother, but she still didn’t lose anything.
Then, a few years ago, I “saw the light” and switched her to a grain-free, low-carb, high-protein, higher-fat diet. Within months she went from 52 pounds to 36 pounds (a good weight for her) and has stayed there ever since, even though she is now 13 and not that active.
So it can work! Just have never been able to get to to work well for me, ever since I first went on the Protein Power plan in 1997. I reach a brick wall about 100+ poounds from my goal every time, and then never lose another ounce. And so far it is not working for my cat Ming either – who continues to *gain* weight on her low-carb cat carnivore diet.
I’m actually not convinced that domestic cats are solitary. But it depends. They have a hard time adjusting to cats they don’t know, but if it’s their family group, they do fine. The one drawback I can think of is that if you have a cat-family-oriented cat, it’s less likely to bond to its owner, at least as far as I have observed. But if you think about it, with lion prides, that’s family-based too.
Trap-neuter-release activists have found that if you clear all the feral cats out of an area, more cats will move in but if you simply neuter the ferals and return them to their territory, they keep strange cats out and the population stabilizes.
I am currently owned by a tux kitty who knows when I have migraines. She follows me around as it is and often lies at my feet when I’m online, reading a book, or knitting; she follows me around even more and cries outside my bedroom door if I’m headachy.
I want to feed her and the other three girls a raw diet but we need to get settled here after our move and then I need to convince the other adult in the house that it’s a good idea. I compromise in the meantime: they eat kibble, but there is no grain in said kibble. It’s meat-based with a few plant foods thrown in. I don’t have the ingredients list right in front of me but I went out of my way to find something low-carb. The three cats being re-introduced to my household had been vomiting frequently with the crap previously fed to them. They do it a lot less now.
I don’t get dogs. You have to pay even more attention to them than you do to children, and I have never been a touchy-feely kind of mom aside from what attachment parenting techniques I picked up in parenting my younger one. I can’t stand someone bouncing around me being needy 24/7–I was a pretty independent child myself, for one thing. Meanwhile, I’m finding you do need to work with cats a lot more than was previously believed if you want them to be less likely to pick up annoying behavior patterns, and if you want it to be easier to do things like administer medicine and bathe them. If you don’t handle them a lot as kittens it will be an uphill battle.
I’m beginning to loathe the term “omnivore.” I think there must be an incredible amount of overlap in what foods animals tolerate, that while our GI tracts *are* geared toward a certain class of foods, what sorts of enzymes we produce in response to which specific foods is going to vary hugely depending on a lot of factors. So you have cows who get certain B vitamins from the bugs they eat along with their grass, you have dogs who can eat vegetarian (at least for a short time), and you have animals who originally descended from bug-eaters running the whole gamut of gastronomic possibilities.
I mean, that’s what primates are. We’re bug-eaters. The only reason we humans have not drawn the logical conclusion that this makes us carnivores is that for a long time we did not define bugs as animals. Some of us still don’t define *fish* as animals, which is why Catholics can get away with eating them on Fridays during Lent.
At this point as far as I’m concerned “omnivore” means “I can eat foods beyond what my GI tract is equipped to handle and not die soon afterward.” But I suspect that if you scratch an omnivore you will still be able to look at their GI tract and be able to tell where the bulk of their diet should come from.
I was shocked to learn recently that robins eat mulberries. I had always pegged them as bug-eaters, but one had nested in a magnolia in front of our house and she was picking the berries from our tree to feed to her chicks. Bizarre, but no different than orangutans eating salad. By the way, did you know orangs have culture? They released this group of them from a zoo or something and rehabbed them to the wild–well, the poor things hadn’t been in the wild for so long they didn’t know what to do with themselves, so they kind of made it up as they went along. No wonder they’re vegetarian. At some point they must have made a conscious decision that that was a good idea too, and then passed it on to their kids. They could as easily go the other way and get back to bugs and monkeys, of course.
By the way, another thing that annoys me aside from the word “omnivore” is the term “is designed to…” when referring to a living thing’s body parts. It’s one thing if you are a creationist, quite another if you hold to evolutionary theory. I won’t be a hypocrite here, I know it’s a habit and I’ve been trying to kick it myself. Been trying to substitute “is adapted to” instead, and seem to be getting better at it.
I am quite certain than the cat food industry knows that cats are obligate carnivores and they actually understand what the term means. This aside, they are dedicated to the bottom line.
It’s amazing to me how horrified we were that some Chinese manufacturers added melamine as filler to cat food, when the manufacturers’ “correct” recipe calls for lethal amounts of (carbohydrate) filler!
I see my original comment is still awaiting moderation (stuck in the spam filter because of live links?) but I just wanted to clarify my ramblings on gut flora and macronutrient ratios, if I may. Despite the fact that (1) gorillas and our ancestors diverged something like 7 million years ago, (2) we have undergone significant GI remodelling since (we don’t have big hindguts for fermenting a herbivorous diet like they do for one thing, maybe in large part because of our co-evolution of cultural adaptations including toolmaking and control of fire that allowed a shift to a much more nutrient dense diet) and (3) we have come to subsist on very different diets – gorillas on mostly leaves, and human populations on a variety of plant to animal food ratios ranging up to near carnivory, our two species nonetheless still have gut microbiota that apparently put both in the omnivore ballpark. So GI anatomy and microbiota apparently don’t necessarily track each other closely in the evolution of a species. Ungar et al. in the article I quoted in my previous post suggest that the adaptive value of Homo’s putative dietary versatility may have allowed Homo erectus to range outside of Africa, the first hominin to do so. I’m presuming that gut microbiota had an important role in allowing such versatility (perhaps wrongly?) and therefore wondering what role it still plays, if any, in allowing humans to subsist in good health, almost to the present day, on a variety of diets – Inuit to Kitavans and so forth.
I’m sure gut microbes play a role since there are God only knows how many of them residing within us. They play a large role in herbivores because herbivores get most of their protein from digesting their dead gut microbes.
always a pleasure to read such posts. unlike dogs cats are useless in my opinion
Hm…
First of all – it’s depends on cat breed. Some of them – can’t live without mice and birds, but others – need only pedigree and similar food.
And, the first group, as a hunters – more indipendent than the second group. Yet, they both usually full of love and want to share it with their human friends.
So, I deeply persuated, that any cat may become useless ONLY if the owner don’t care about that. it’s a pity, my great Maine Coon is on-half without daily work (speaking about mice), but I doing my best to help him be happy in that world!
I could never understand why people who don’t like cats feel the need to really voice that opinion. I know plenty of people who don’t like dogs, but you’d never know it. It’s somehow acceptable to dislike cats (and prob why people who DO like cats are so much more vocal). Would anyone ever say “I hate your kids. I can’t see why anyone would like them”? The fact is – dog OR cat – people love their pets. And by loving an animal we’re not trying to say that animals are better than people. No. The reason why I love my cat and people love their animals is that they are celebrating a primal emotion, a connection to our paleo-past when coming into contact with an animal (always wild then!) was spiritual. There is a kinship to animals, an ability to see how animalistic we still are by how humanistic they can be, by how many traits we share in common. Also, when I look at my cat, I’m amazed at what a perfect hunter he is. When I look at my dog, I’m amazed at how adept his sense of smell is, how powerful they are. Let go of any prejudgement and let yourself just respect how “neat” they are.
Wow I have several cats and three dogs. We all work together and live well together. Cats yes they fetch, the come when you whistle same as the dog. They go outside and present me with mice sometimes two or three at once. They are affectionate as much as the dogs and yes the dogs and cats sleep together when its cold.
What really struck me odd was your reference to adopting out a child because he or she may or may not act appropriately to your liking. I have four adopted children and one bio and I find that offensive. On the other hand we adopted most of the cats we have because they were left out to die or thrown from a car by our house. No matter how you feel about an animal there is no need to hurt them or feel the need to speak on behalf of an animal when you are not sure what they can’t or can do.
By the way I can’t get one of my dogs to come when he is out or fetch.. Takes the darn freezbee and runs. But I love him anyway.
[...] think this was the first post I read: Hard wired to the past, which I may have like it, in part, because it is about [...]