Friday, March 29, 2013

"Humans Have No Known Anatomical, Physiological, or Genetic Adaptation To Meat Consumption."

Dr. Christina Warinner earned her Ph.D. from Harvard University in 2010, specializing in ancient DNA analysis and paleodietary reconstruction.  She has done archaeological excavations across the globe, from the Maya jungles of Belize to the Himalayan mountains of Nepal, and she has pioneered the biomolecular investigation of archaeological dental calculus (tartar) to study long-term trends in human health and diet.  In this video, she debunks the PaleoDietTM, and any other diet philosophy founded on the claim that humans "evolved to eat meat," or have genetically adapted to meat consumption, or have a physiological need to eat flesh.

At 3:15 she states the bald fact that belies such claims:  

"Humans have no known anatomical, physiological, or genetic adaptation to meat consumption."   

The only known human genetic and physiological adaptation to animal food consumption consists of lactase persistence, which occurs only in a relatively small portion of the world's population (primarily people having northern European ancestry).  This adaptation does not dictate a dietary requirement for milk products, but only confers persistence of the ability to digest milk sugar into adulthood.

In contrast, all humans have numerous very specific anatomical, physiological, and genetic adaptations to consumption of fruits, vegetables, nuts, and seeds.


Charles Grashow said...

"Humans are classic examples of omnivores in all relevant anatomical traits. There is no basis in anatomy or physiology for the assumption that humans are pre-adapted to the vegetarian diet. For that reason, the best arguments in support of a meat-free diet remain ecological, ethical, and health concerns.

[Dr. McArdle is a vegetarian and currently Scientific Advisor to The American Anti-Vivisection Society. He is an anatomist and a primatologist.]"

"Christina presents herself as an Archaeological Scientist who studies the health and dietary history of ancient people using bone chemistry and ancient DNA. She then proceeds to call the Paleo Diet “one of the fastest growing diet fads” that “has no base in archaeological reality”.

Every student of science knows that it is impossible to prove anything with certainty and what scientists do, at the most, is assemble more and less dubious facts to tell a story that will hopefully make sense. This framework should be all the more intuitive when reconstructing historical phenomenon, in this case diet, is at stake. This is the reason no scientist can claim to offer certainty regarding ancient diets, no matter what his professional credits are or how confident he or she sounds."

" would have loved to see Peter Ungar’s reaction to her statement regarding dentition. Peter Ungar is The best known teeth expert among current physical anthropologists. His reputation got him a million dollars to build a “Biting Machine” to test the suitability of ancient teeth to handle different types of food. Here is a video (18:50 minute) in which you can see Ungar’s machine and hear him state that unlike our predecessors, our teeth are evolutionary adapted to handle meat. In a 2004 paper he stated with appropriate scientific cautiousness: “meat seems more likely to have been a key tough-food for early Homo than would have USOs “[tubers, M.B]. I would also love to see Mchenry’s reaction to the statement that we have big molars. McHenry developed the Megadontia Quantient and shows that in relative terms our molars are less than half the size of our evolutionary predecessors. I will leave it to you to judge how this state of scientific knowledge regarding teeth and gut can be reconciled with a statement denying any “known anatomical, physiological or genetic adaptation to meat consumption” and specific statement about the inadaptability of our dentition to handle meat."

Horacio said...

Is this Fools Day?

Charles Grashow said...

An interpretive history of the cholesterol controversy

"The first four reviews in this series traced
the gradual accumulation of evidence, evidence of several
different kinds, supporting the lipid hypothesis. They
tracked the history from Anitschkow’s 1913 classic work
on the cholesterol-fed rabbit model to the breakthrough
1984 Coronary Primary Prevention Trial, the first large, randomized, double-blind primary intervention trial showing
that decreasing blood cholesterol (using cholestyramine) significantly reduces coronary heart disease events. At that
point, for the first time, decreasing blood cholesterol levels
became an official national public health goal. Still, only a
small fraction of patients at high risk were getting appropriate cholesterol-lowering treatment, and a number of important clinical questions remained unanswered. This
final review in the series traces the early studies that
led to the discovery of the statins and briefly reviews the now
familiar large-scale clinical trials demonstrating their safety
and their remarkable effectiveness in reducing coronary
heart disease morbidity and mortality"

Part 1 -

Part 2 -

Part 3 -

Part 4 -

Part 5 -

anand srivastava said...

So I guess you know longer believe in evolution, or at least that we are primates. Because every known primate eats insects. And the closest primate to us also eats meat. If you do think of one that doesn't eat insect do tell, I am curious.

I think Dr. Warinner was trying to be hyperbolic to drum up interest for her presentation. Happens all the time.

Charles Grashow said...

A critique of:

A Hypothesis to Explain the Role of Meat-Eating in Human Evolution
Katharine Milton
Department of Environmental Science, Policy, and Management
Division of Insect Biology
University of California, Berkeley

Charles Grashow said...

"when one researches the diets of anthropoid apes in the wild, one finds that none of them are vegan! Most anthropoid apes eat around 2% to 3% animal products mostly in the form of insects, but they also do on occasion eat small mammals. They are not vegan! What then does this say for humans? After all, as mentioned, we are likewise anthropoid apes; we do have 4 canine incisors. While these incisors are small and only make up 4 of 32 teeth, they are still there and would be in keeping with the small amount of animal products that anthropoid apes in the wild eat. They are not there by chance, one can be sure of that."

Charles Grashow said...

Correcting the vegetarian myths about ape diets

George G said...

"Bloody Baboons
Baboons eat a lot more meat than other primates. Mostly these are insects, snails and other invertebrates. But they also eat small mammals if they get the chance. They commonly kill and eat hares, birds, young antelopes and even fellow primates such as bushbabies and young vervet monkeys. Their large size also allows them to overcome and kill, when hunting in a group, larger prey such as gazelle kids. They have large impressive canines, their main weapons of defence and offence. Yellow baboons have been observed hunting down hares and digging out burrowing mammals. The chacma and olive baboon gorges on grasshoppers and scale insects when there are infestations of these insects, ignoring all other food. Olive baboons also hunt hares and larger mammals like vervet monkeys and infant gazelles. Those living on the coast may hunt molluscs, crabs and other marine life."

George G said...
This comment has been removed by the author.
George G said...

Most monkeys eat some meat, and seem to prefer it, going to great effort and risk to procure it.
But it is incredibly difficult to catch larger animals.
So there seems to be a trend that the more intelligent the primate, the more meat they can catch.
Which indicates to me that a fairly large proportion of a humans diet would often have been meat.

George G said...

OK, just watched the Christina Warinner video.
Excellent, and agree with the points she makes, thanks for posting that.
She did say that of course the paleolithic people would have eaten some meat.
And obviously been very diverse and depended on the region.

Swede said...

Weak choice. Where do you fall on the isotope spectrum?...

The rest of the time she talks about how modern plants & vegetables are different from the past.

This might convince a rebellious teen.

George G said...

I don't know much about the isotope spectrum.
I just accepted her argument that you can't read too much into it.
I have to disagee with her statement (and the title of this post)
"Humans Have No Known Anatomical, Physiological, or Genetic Adaptation To Meat Consumption"
Humans must have the digestive adaptions to eat meat, otherwise it would make us sick, like it does true vegetarian animals, because they don't have the specialised digestive mechanisms to digest meat.
Our teeth and mid sized gut make it obvious we have evolved to omnivores, as mentioned in the first comment.

Matthew C. Baldwin said...

Typical scientistic over-reach. She knows of no adaptations? What hogwash. Teeth. Digestive enzymes (esp. proteases and peptidases, but also lipases). Heavy requirements for vitamin-A (the real stuff, not the beta-carotene precursors) and the animal-based B-vitamins, especially B-12. The role of saturated fats in health. We are omnivores, plain and simple, and evolved to be so. It's absolute garbage that there's no zoological, anthropological or archaeological evidence of this.

Healthy Longevity said...

I wonder how much people commenting here know about experimental atherosclerosis in nonhuman primates. Are they not aware that feeding a baboon with a diet rich in eggs and butter develop atherosclerosis that resembles the structure of that in humans. Perhaps the semi-meaty diet partly explains why free ranging baboons also develop atherosclerosis. Macaques have been observed to suffer from heart attacks at about the same rate of high risk human populations when fed a diet rich in cholesterol and satiated fat.

George G said...

The largest study of centenarians, the New England study,
found that patterns of diet varied widely from strictly vegetarian to extremely rich in saturated fats.

I really don't think a high vegetable diet is necessarily better than high meat and fat, or vice versa, for all people.
Maybe it depends more on the individual and their genetic weaknesses ?

Charles Grashow said...

Healthy Longevity said...
Perhaps the semi-meaty diet partly explains why free ranging baboons also develop atherosclerosis.

Can you provide studies that shoiw this?

Healthy Longevity said...


The researchers found aortic lesions in a large number of wild baboons. As the researches believed that intake of animal food is negligible in wild baboons, they concluded that this could not explain the lesions. However if George is correct and wild baboons do eat a lot of animal matter, then this may partly explain the frequency of aortic lesions found in these baboons.

In experiments on baboons, as with other nonhuman primates, atherosclerosis is typically induced or accelerated by the long term feeding of dietary cholesterol and/or saturated fat.


It is not surprising that in a homogenous populations where saturated fat intake is universally high that a portion of the centenarians eat a diet rich in saturated fat. However if you look at the parts of the world with some of the highest rates of healthy centenarians (ie the Blue zones) you will find that these populations were traditionally plant based.

Frank said...


And you are not over-reaching here?

I'm not aware that human have heavy vitamin A recquirement.

Nor that b-12 is animal-based.

Nor that saturated fat have been shown to promote health.

Typical low-carber lies that have been repeated enough to become a ''truth''.

Don said...

For those people, including McArdle and Ungar, who might assert that modern humans have dental equipment well-adapted to eating meat, I suggest an experiment.

The next time you want to eat meat, start with a whole, unskinned animal. Without using any type of tool, using only your hands and teeth, consume the animal's flesh as quickly as possible.

I stipulate that you can't use fire or any tool including knives to process the animal before putting it in the mouth. If you use fire or a tool, you are modifying the flesh to make it more suitable for your dental equipment, not testing how well your dental equipment is adapted to eating flesh.

Given that prehistoric humans had no control of fire, and that tools like knives are means of adapting food to our dentition, this is the only way to test how well our dentition is adapted to eating flesh.

Then, compare how quickly you can consume a given quantity of flesh to how quickly a wolf or dog can consume that flesh.

Then, compare how easily you can masticate raw flesh, to how easily you can masticate raw fruit or sweet potatoes.

I don't believe that raw animal flesh is softer than fruits, nor that raw flesh is softer than raw tubers. I can more easily chew rraw sweet potatoes than raw flesh. Maybe you have different dental equipment than I?

Dental reduction is an adaptation to soft foods. All human teeth (not only molars) are smaller than those of other primates on a relative basis. This indicates adaptation to soft foods. You decide, which is softer and easier to chew, raw whole beef or raw fruits.

Humans have exactly 0 requirement for retinol, according to the Food and Nutrition Board of the National Academy of Sciences.

McArdle is flat wrong if he believes that we have no preadaptation to a plant-based diet. I don't know how anyone familiar with primates could make such an assertion. Humans have sensory, manual, locomotive, digestive, and metabolic adaptations to a plant-based diet.

Better yet, start by hunting without any tools and without the aid of any natural omnivore (such as the dog) or carnivore (such as a falcon or hawk). The very fact that humans use these other animals as assistance for hunting is evidence that humans do not have the same adaptations to hunting and meat-eating that these animals have.

Don said...

"Given that prehistoric humans had no control of fire, and that tools like knives are means of adapting food to our dentition, this is the only way to test how well our dentition is adapted to eating flesh."

I meant, prehistoric human ancestors of the vintage studied by Ungar.

Don said...

BTW, Ungar has written:

"Interestingly, as suggested by Lucas and Peters (46), another tough pliant food they would have had difficulty processing is meat. In other words, the early hominids were not dentally preadapted to eat meat—they simply did not have the sharp, reciprocally concave shearing blades necessary to retain and cut such foods. In contrast, given their flat, blunt teeth, they were admirably equipped to process hard brittle objects. What about soft fruits? It really depends on the toughness of those fruits. If they were tough, then they would also need to be precisely retained and sliced between the teeth. Again, early hominids would be very inefficient at it. If they were not tough, then the hominids could certainly process soft fruits. "

Charles Grashow said...

Vascular effects of a low carbohydrate high-protein diet

"the macronutrient changes in the LCHP diet used here mimic the diets commonly used in humans, where reduced carbohydrate intake is generally accompanied by increased protein and fat intake. Interestingly, multiple results in mice on the LCHP diet paralleled those reported in clinical trials including reduced weight gain without significant changes in serum lipids or other markers of cardiovascular risk (10, 11), further reinforcing the potential relevance of this model.

Exacerbated atherosclerosis occurred on the LCHP diet independent of significant alterations in traditional atherogenic serum lipids, serum inflammatory markers and histological indicators of inflammatory infiltration. We did detect a significant increase in serum NEFA levels on the LCHP diets (Table 1) but this was not correlated to an increase in serum measures of inflammation. Importantly, there was no evidence of increased leukocyte infiltration in plaques from mice on the LCHP diet. We did not detect a significant difference in either circulating oxLDL or tissue markers of oxidative stress. Together these data suggest that neither an increase in the inciting signals nor in the inflammatory cascade are responsible for the increased atherosclerosis seen on the LCHP diet when compared with the similarly high-fat WD.

Although caution is warranted in extrapolating from such animal studies, these data at least raise concern that low-carbohydrate high-protein diets could have adverse vascular effects not adequately reflected in serum risk markers. Moreover, these observations demonstrate important pathophysiological vascular effects of nonlipid macronutrients that are dissociated from weight gain. These features provide a unique model for understanding mechanisms of atherogenesis and neovascularization that may have implications for efforts to combat obesity and reduce its complications."

A Look at the Low-Carbohydrate Diet

"Traditionally, the atherosclerotic risk profile that is associated with specific diets is determined by measuring intermediate risk factors, such as levels of low-density lipoprotein cholesterol, blood pressure, and C-reactive protein. The work of Foo et al.
suggests that the HPLC diet might increase the risk of cardiovascular disease through mechanisms that have nothing to do with these “usual suspects” and so provides a
note of caution against reliance on the traditional cardiovascular risk factors as a gauge of safety."

The Humane Hominid said...

"Apes eat meat" is actually an argument in favor of her position, not against it. If it's common amongst other primates, and not unique to humans, then it is not a derived human adaptation.

George G said...
This comment has been removed by the author.
George G said...

The Humane Hominid said...
"Apes eat meat" is actually an argument in favor of her position, not against it.

Good point, I suppose that is correct.
But the statement "Humans Have No Known Anatomical, Physiological, or Genetic Adaptation To Meat Consumption" is not exactly clear that she means adaptations unique to humans after they evolved from primates.
In fact its kind of confusing when used in the overall thrust of her argument.
So what does it mean if humans have lots of meat eating adaptations, but none that unique to just humans - not much.
Anyway, why do humans find the aroma of roasting meat and fat so alluring ?
We don't learn it, it is instinct.
I think that could be a recent adaption, that is uniquely human.

Don said...

Do you have some the peer reviewed evidence that all or almost all humans find the odor of roasting flesh and fat alluring?

By what method did you determine that the attraction some people may claim to have to the aroma of roasting flesh/fat is not learned?

If humans find that odor so alluring, why do women use floral, not roasted meat perfume? Why do people use flowers or floral fragrances in their homes, not roasted meat odor?

I am sure that if people really found roasted meat odor alluring, the perfumers would have found a way to bottle it for use on body or in home, so as not to pass up a gold mine.

If humans are adapted to consuming animal flesh, then why do so many people dislike organ meats, particularly liver? No dog (omnivore) will turn down offal.

Why do so many humans find the sight of road kill, carcasses, blood, and guts disgusting, not appetizing? To the extent that we currently hide the slaughtering process completely from view in modern civilized societies?

BTW, according the the Smithsonian Museum of Natural History, we have no unequivocal evidence that modern humans are descendants of either Homo habilis or Homo erectus, particularly since Homo habilis appears to have coexisted with Homo erectus for ~0.5 million years, and Homo erectus appears to have coexisted with Homo sapiens 143,000 years ago. Click on The Unknown Click on The Unknown

Moreover, "Human evolution is speeding up. Around 40,000 years ago our genes began to evolve much faster. By 5000 years ago they were evolving 30 to 40 times faster than ever before and it seems highly likely that we continue to evolve at this super speed today. "

Please note that Christina was talking about modern humans, not Homo habilis or any other ancient species.

If human genes have evolved significantly in the past 40K years, and we have no certainty that we descended from Homo habilis, then the shape of the teeth of these ancient species studied by Ungar et al may actually have virtually no relevance to determining the dietary adaptations of modern humans.

swircle987 said...
This comment has been removed by the author.
swircle987 said...

Wonderful explication of the fallacies of the so called "Paleo Diets!" The best part is that you initially intended this site to be pro-paleo, but because of your own research decided to change your stance. Love it.

Thank you for your work, especially providing so many links to your sources. I reposted this link as part of a response to a suggestion I received along the paleo direction... . ^_^

Charles Grashow said...

"The intake of plant foods by hominids was most plausibly and conceivably minimal. This is due to their limited, seasonal availability; the physiological ceiling on fibre and toxin intake; the biological evolution of early Homo physiology; along with the technological, spatial and temporal limitations of obligatory pre-consumption preparations. Consequently, evolutionary arguments for the consumption of what are quite blatantly Neolithic foods are rendered paradoxical and absurd. Starches are neither ‘Paleo’; nor does our evolutionary biology sanction them as ‘safe'."

ram kishan said...

The paleolithic diet (abbreviated paleo diet paleodiet), also popularly referred to as the caveman diet, Stone Age diet and hunter-gatherer diet, is a modern nutritional plan based on the presumed ancient diet of wild plants and animals that various hominid species habitually consumed during the Paleolithic era—a period of about 2.5 million years which ended around 10,000 years ago with the development of agriculture and grain-based diets. In common usage, such terms as the "Paleolithic diet" also refer to the actual ancestral human diet

Benefits of paleo diet

gunther gatherer said...

Hi Don and thanks for this clip.

I was wondering if you care about GMO crops in your diet (mostly corn and soy, but also beets sometimes). New research in France is showing that GMO "Round-up ready" corn either with or without Round-Up causes massive tumours in mice when they are allowed to live their natural lives. This is the main reason Montsanto will not release their study results over 90 days. It is a massive scandal here and there is a movie about it.

The movie, in French, is called "Tous Cobayes" (All Guinea Pigs). Here is a translated excerpt:

Diana said...

"Perhaps the semi-meaty diet partly explains why free ranging baboons also develop atherosclerosis. "

Guys - I am not going to do an exhaustive google search for this, but I have read that male baboons are an extremely competitive lot, and that atherosclerosis is greater amongst the lower status males. When a top status male (an "alpha") loses his place in the pecking order, he often has a heart attack and dies.

Sound familiar?

Their heart disease issues have nothing to do with their diet, and everything to do with their mentality.


Your example of tearing apart and chewing up meat without fire is ludicrous. The point is, control of fire is at least 125K years old. The human genome has adapted to eating the foods that controlled fire enables us to eat.

Does anybody eat raw yams?

You are a nutcase, pushing one nutty extreme theory after another. I predict that within 5 years, you'll do another 180 degree turn, or a 165 degree, or something, and you'll be advocating that we eat an all Cheez Whiz diet.

Ashley Smith said...

You people are all zealots. There are so many cranks on the Internet with paranoid conspiracy theories. Everybody from the Paleolithic Diet people to the Vegans.

They are all fad diets. All of this information is wrong.

ALAN ARAGON is the only reasonable, unbiased scientific guy in the entire Blogosphere. He is very rare because he has a real knowledge base about genuine nutritional science .

He has worked with many professional athletes such as Derrik Fisher , formerly of the Lakers, Steve Austin and many more.

Extreme zealotry,poor quality studies, misrepresented/misinterpretted studies, is all I see. And this applies to both here and the Paleolithic Diet sites.

Pure crank madness......

Real scientists are nowhere near knowing the optimal diet for humans. Only a complete understanding of human cellular biochemical operations will give us this ability. We are still unraveling how cells work.

The only people Internet cranks and Bloggers convince with their nonsense are non- scientists. They are excellent at that, which is why they are in business making a profit off of the uneducated and gullible.

Ashley Smith said...

I agree, Diana.

Anybody claiming to know the optimal diet for humans is outright lying or is genuinely uninformed. The unknowns about nutrition are unbelievably enormous and vast . The uncertainty is massive. Real scientists admit to all of this.

There is much, much, much more to be learned about nutrition , how cells work and how nutrients affect them. We are ALL winging it. It's a crapshoot. We are all taking some risks with our diets. Far too little is currently known.

These Internet Blogger cranks are 100 % certain. They have an answer for everything. And that answer is always certain. They are never wrong about anything either- not even the slightest details.

Diana said...


I hear a lot about Aragon. I am allergic to gurus, but I'll check him out.

Agreed that no one knows what the optimal human diet is. My two cents: check out the longest lived family member and emulate him or her.

In my case, an aunt lived until 104. She ate a moderate diet, but her favorite foods were orange juice, grilled cheese sandwich, and hamburgers. Which to be honest she did not often finish. Her appetite was modest.

Oh yeah, she never exercised.

Go figure.

city said...

thanks for share....

Rex said...

Actually, the "ideal" human diet has already been mapped out fairly well by Traditional Chinese Medicine along with other more traditional forms of medicine in other parts of the world. Every human being has a slightly different constitution. Some people gain weight more easily, others are prone to feeling hot or cold, etc. In addition to these constitutional differences, people may need more or less of certain foods depending on health history, current lifestyle and time of year. That said the "ideal" human diet as recommended by TCM is as follows (by weight):

Grains: 35-60%
Vegetables: 20-25%
Legumes: 5-15%
Fruits/Nuts/Seeds: 5-15%
Animal Products: 0-10%

This diet closely resembles that advocated by most health "authorities." Looking at this diet, it's easy to understand why both the paleo crowd and vegan crowd make valid points but may also be too restrictive. Between the two, veganism is certainly the better choice, but animal products may be necessary for some people. I know I am better off with them than without them. Perhaps if we all treated animal foods like medicinal supplements to a plant-based diet we would all be better off health wise and there would also be less controversy and greater appreciation for individual differences?

Don, I haven't seen a new post in a while...Looking forward to your next one!

Kris Nelson said...

For all the fallacious arguments that Man has adapted to eating animal-flesh, or that other animals do it so we can/should do it too, as a reason to continue eating animal-flesh, consider the following.

Just because you CAN do something, doesn't necessarily mean you SHOULD do it. Examples of a baboon being hungry, and eating anything it can to survive are not arguments in favor of health and longevity or what the animal is INTENDED to consume. THere is evidence to show the detrimental effect of animal-flesh consumption of the animals that have been able to procure animal-flesh, but were NOT INTENDED to do so according to their physiology. They CAN do it to survive or because they CHOOSE to, but it is not beneficial in the long term.

Because A, B, C, etc animals that are similar in some ways to us eat other animals because they CAN, does this mean they SHOULD? No, they do what they do without knowing the consequences of their actions, merely focusing on survival. Should we emulate such unintelligent behavior because they resemble us in some ways, and therefore base our eating habits on the habits of other animals? No.

Should we copy what other animals do just because they do it? No.

Should we keep doing things just because we have done it in the past where we have learned similar strategies to survive, to eat whatever we could get our hands on in order not to die? No. If we needed to, we could eat other human-animals, does that make it acceptable and desirable to do so? No.

Just because we have learned something in the past and made it part of our living condition, does that make it necessary to continue engaging in such a condition? No.

For example, we have learned to kill each other for along time. Should this past condition merely be continued because it has the nostalgic attachment of being "ancient" and "old" and "part of tradition" and therefore a necessary function of our survival? No. The long-term use of a learned condition is not validation to continue engaging in a past tradition, behavior or habit.

Please develop your reasoning skills and think critically before assuming past behavior merits continued acceptance.

Physiologically, Man is not designed to be a consumer of animal-flesh, regardless of the habits, behaviors and traditions we have been accustomed to engage in without proper critical thinking.

We can continue to do things without being consciously aware of the bigger picture, or we can become consciously aware of the false traditions we are conditioned to engage in, and choose to alter our actions, behavior and habits in accordance with what is right, good and true.

Wake up from your slumber, open your eyes.


tomR said...

Don wrote "Without using any type of tool, using only your hands and teeth, consume the animal's flesh as quickly as possible."

You commitet two dishonesties in a single sentence! First is about the use of tools. Humans (genus homo) => use of tools. There are no homo species NOT using tools. Using tools is fundamental to being human. Requirement to remove this important human feature makes your challenge dishonest and biased (towards non-tool-using animals winning).

The second dishonesty is in requirement to consume the food as quickly as possible. Except for some sport we, humans just don't do it - in fact we do the opposite! We preserve food for long-term storage (eg. meat can be preserved as pemmican) and consume it regularly, rather than eating everything at once. This is how humans work.

tomR said...

Don wrote "humans do not have the same adaptations to hunting and meat-eating that these animals have."

Human adaptation to hunting is the ability to throw long-range weapons with high precision. Which might be one of the primary reasons for the start of brain growth - long range accuracy itself requires lot's of neurons, as averaging signals over many neurons is the way we reduce the noise. Besides trying to hit a moving object requires ability to implicitly predict the position of the object based on its velocity, distance to it, direction of its movement, then calculate appropriate ballistic trajecotry, then control the throwing precisely enough to fit it.

Hunting made us intelligent kind of stuff...

Don said...


Tools are not anatomical, physiological, or genetic adaptations. Will you be willing to say that the fact that we can do deep sea diving or travel to the moon using tools proves that we are BIOLOGICALLLY adapted to deep sea diving or space travel?

My challenge is to check whether you have anatomical or physiological adaptation, which requires the removal of tools. We use tools to overcome the limits of our biology.

Preserving meat as pemmican is CULTURE not biology, just like making computers is CULTURE (learned behavior) not written in our genes.

"Which might be one of the primary reasons for the start of brain growth....Hunting made us intelligent kind of stuff."

You just converted a hypothesis (hunting may have influenced our brain evolution) into a fact in your mind.

"Besides trying to hit a moving object requires ability to implicitly predict the position of the object based on its velocity, distance to it, direction of its movement, then calculate appropriate ballistic trajecotry, then control the throwing precisely enough to fit it. "

Have you ever seen herbivores run to escape a predator, or fight another in self-defense or for mating rights, or jump a barrier? Have you ever seen a primate swing from tree-to-tree, while the wind blows the limbs? Since velocity and trajectory are relative quantities, the same types of calculations are required regardless of who/what is moving. Success at these activities also requires predicting the position of the target based on velocity, distance, direction, etc. and also calculate the appropriate response and gauge muscular effort to fit the need.

Humans are not particularly unique in their abilities to adjust muscular effort to hit a target. Consider the nectar-feeding hummingbird for example. We just express this ability differently because of our unique anatomy.

Moreover, how about threading a needle, sewing clothing, weaving a basket, making and using a snare for picking fruits from the ground, engaging in conversation for co-operative efforts, and keeping a cognitive catalog in memory of the edible, medicinal, and toxic plants in your home range, and when each is available, and for what application (rainforest populations have up to 2000 plants memorized), and a myriad other things humans do that also evidently "require many neurons"? Is it possible that any or all of these "made us intelligent kind of stuff"?

Throwing a spear or other projectile is a LEARNED behavior, just like typing at a computer, i.e. culture, not biology.

The fact that we can learn to do something (e.g. type at a keyboard) does not show us that doing that (typing) made us intelligent. It is just as likely that the ability already existed, untapped, then got applied through learning.

These animals, some carnivorous, some not, are manifesting larger brains without increasing their DHA intake or using projectiles.