Ray Audette (whose book NeanderThin is a treasure that I will be forever grateful for and a major early influence on me) wrote a good point about the details of Paleo not being as important as the broader concepts. I find the details like the Stone Age consumption of groundnuts and tubers interesting not so much because of the details of what was consumed as the questions they raise about common assumptions made in Paleo diet circles. These questions undercut the certainty of what I'll call "knee-jerk Paleo," in which all legumes and tubers are ruled out for everyone because "they aren't Paleo." I'm all about asking lots of questions and much less about coming to final conclusions. Science to me is more about asking questions and curiosity rather than final answers and certainty. In other words, it's more Taoist than fundamentalist.

When I learned that peanuts and groundnuts and some tubers (mainly legume tubers, interestingly) are edible raw and commonly consumed by hunter gatherers who have access to them, this raised some interesting questions for me and revealed that "Paleo" may be more subtle and complex than the do and don't eat lists of NeanderThin and The Paleo Diet suggested. These foods are still questionable, in my view, but I am less liable to simply rule them out for everyone than I was after I read those books. It's interesting that Boyd Eaton allowed legumes in his early version of Paleo, and other Paleo-type diet proponents, like Dr. Kurt Harris, refuse to exclude legumes without more evidence. There's also the interesting possibility that even somewhat toxic foods may have beneficial hormetic effects (see the fascinating writings of Todd Becker and the uber-brilliant Stephan Guyenet on this).

David Wrote: "Peanuts would never have been a staple."

Agreed, definitely not peanuts, since peanut consumption reportedly only dates back 7,600 years (in Peru). Perchance did you mean to include the similar African groundnuts that our Stone Age African ancestors consumed and that African hunter gatherers still consume today? I don't know how much groundnuts and other legumes were eaten during the Stone Age, so I can't rule out that legumes as a whole reached staple levels, though I do suspect that they were less substantial contributors to the diet than meats, fruits, honey, insects, and roots and tubers. Recent hunter gatherers don't seem to be afraid of groundnuts or legume tubers, which again, doesn't guarantee that they're optimally healthy or won't harm anyone and I certainly have no intention of eating groundnuts or peanuts just because Stone Agers did, nor just because HGs and modern Africans still do. I'm not into blind re-enactment. I do what works for me--the tricky part is figuring out what works best for me out of all the many foods, in the somewhat longer run. 

Here's some info on recent HG consumption of groundnuts:

"[G]round nuts appear in great profusion during and after the rainy season, when they form the principal part of the daily menu" (The Khoisan peoples of South Africa: Bushmen and Hottentots, By Isaac Schapera, when they form p. 93)

"Then the ground nuts come in and more wild bulbs, which seem to flourish through the winter." (The Naron: A Bushman Tribe of the Central Kalahari, By D. F. Bleek, p. 7)

Ron Hoggan wrote: "Given sufficient time eating them, I think we would eventually become fully adapted to many foods, but as you said, how long that would take is an open question."

Hi Ron, 
Another factor is that we modern humans tend to have a goal of optimizing our diet for reasons like health, performance, longevity and well-being. Nature doesn't "care" about these goals. It tends to operate in a way in which species adapt enough to foods to enable survival, procreation, and enough mature adults around to care for the young and thus ensure the long-term survival of the species. This doesn't have to include optimal health adaptation (see again the Giant Panda example). There are multiple potential reasons why a food eaten during the Stone Age might not be optimal for a particular individual today. Our current rough notions about an evolutionary template are a starting point, not the final answer for everyone, and I suspect you agree with this.

RH: "Another challenge with the Paleofood paradigm is that humans have spread so widely around the globe that each of us may have genes from any of a number of environments, and a full or partial adaptation to some of the foods derived from those various places, but we are unaware of the foods to which we are best suited."

Agreed, and there is suprising variation in genes and traditional diets even between adjacent regions. For example, the tallest African people live adjacent to the shortest, as I recall.

RH: "For instance, there may even be people who are fully adapted to eating ground nuts and peanuts, while most of us may be unable to eat them."

It's possible. I certainly can't rule it out. I'm more about asking questions than providing answers.

RH: "The most extreme example is peanut allergy."

Yes, peanut allergies are apparently common. There's mixed evidence suggesting that the type of cooking and/or processing of peanuts may contribute to the allergenicity:

Don’t Feed the Children: the growing problem of peanut allergies
http://eatingscience.wordpress.com/2011/12/09/dont-feed-the-children-the-growing-problem-of-peanut-allergies/
"Peanut allergies are more common in the U.S. and the U.K., where people tend to eat peanuts roasted, than in Asian countries like China, where peanuts are usually eaten raw or boiled. Studies have shown that the allergic response to one of the peanut proteins, Ara h 2, is increased by the roasting process."

RH: "But I suspect that if their adaptation is only partial, they could quickly shift to some meat in their diet, if only because the ancestors they share with other bears were clearly able to eat meats, but perhaps the panda GI tract has reached a point of no return."

It's an interesting question that I don't know the answer to. I did read somewhere that female giant pandas in the wild seek out insects and other forms of meat/fat when they "want" to get pregnant (which is very rarely mentioned anywhere, perhaps because giant pandas earn big bucks when they are portrayed as cuddly pure "vegetarians"). It's fascinating to me that scientists claim that the Giant Panda has the second-most carnivorous physiology among bears, after the polar bear, yet bamboo accounts for 99% of its diet. I love how this contradicts so many assumptions in every quarter and raises so many counter-intuitive questions.

RH: It is sufficiently altered that such a shift would not be likely. But how many of us would have expected Icelandic ponies to be able to survive eating fish? 

Fascinating. Thanks for sharing that. It undercuts the vegan argument that eating meat or fish requires lots of adaptation. Do you have a cite? By coincidence, I found that there is a connection to Icelandic horses with my native homeland of Vermont: http://www.squidoo.com/what-do-icelandic-horses-eat-fish-

RH: While I agree that partial adaptation is one weakness in the Paleofood paradigm, another, much larger weakness is that most of us are sufficiently different in our genetic heritage, and hence our environmental adaptations, that it is impossible to assert a universally optimal human diet - even if it is strictly Paleo. In fact that is the central thesis of my current writing project. The Paleo perspective only gets us so far. 

Interesting, that was my hunch when I first learned about Paleo too, but with all the genetic mixing and dietary changes over the last ten thousand or so years, it's even harder to guess which foods one's genes might have become recently more adapted to than it is to figure out what's "Paleo." I have learned that I have a gene for lactase persistence, which does match the pastoral background of my Irish ancestors. Despite that, I find that I don't seem to digest pasteurized cow's milk or ghee as well as "Paleo" aka "NeanderThin" foods. Raw sheep's cheese is easier for me to digest than any cow's cheese or cow's-milk-ghee. Pastured butter seems pretty neutral for me at the moment. I haven't noticed much in the way of either plusses or minuses from it. It's interesting that sheep's cheese seems to be easiest for me to digest among dairy products tried so far and sheep are a traditional animal in Ireland, fitting well with my mostly-Irish ancestry. Is there a true link? I don't know.

RH: "In my book (if I ever finish it) I also argue that we can get a sense of most of the foods to which we are best adapted by carefully following a variety of our own signs such as blood pressure, fasting glucose, HbA1c, weight, ketone body production, energy levels, thyroid function, mental acuity, etc. etc. as we experiment with various diets."

Yes, I suspect that self experimentation is probably a better indicator than genes and it's my main tool for the dietary fine-tuning I do now. 

RH: In an uncontrolled environment, over sufficient time, those with optimal health will ultimately outstrip less healthy people in survival and reproduction. 

That happens in the wild, but it didn't happen in human history. Instead, during the Neolithic Revolution, the sickly city folk out-reproduced, conquered, enslaved and exterminated the healthier remaining hunter gatherers, whose numbers continue to dwindle while the cities continue to grow.

Thanks for your excellent post, Ron. The consistent quality of your posts is a wonder, a jewel to be treasured. 

Most of my online time is spent at the raw Paleo forum these days, and I don't mean to undercut this wonderful forum where I received much of my early education on Paleo, but your presence and contributions there would be greatly savored by me. I consider raw Paleo to be the next, better step beyond standard Paleo, which Ray Audette hinted at in his classic treatise, NeanderThin, which was one of the influences that led me in the raw direction. So I entreat you to consider joining us there and sharing some of your wisdom. I have heard that you have serious disagreements with Tyler Durden, but so have I, and it hasn't stopped me from posting or learning interesting things there. Besides, having someone with very different views there challenges my speculations and provides for a good sounding board and trial by fire. 

Whatever path you choose, I wish you the best of luck on it, and consider you a kindred spirit and soul brother.