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(Comparative Anatomy and Physiology Brought Up to Date--continued, Part 9C)

Potential reactions to information
in this paper: Part 1

Rationalizations about the Evidence for Omnivorous Diets from the Fossil Record & Comparative Anatomy

Diet gurus excel at spinning rationalizations

One thing many raw/veg*n advocates are very good at is quickly spinning new rationalizations and excuses when faced with new, contrary factual information. It's very easy to spin new rationalizations (which are usually presented with little or no evidence), whereas investigating such rationalizations (only to often find they must be discredited, ultimately) is often very hard, detailed work. (The papers on this site are evidence of this, and it's probably why there are few such investigations to be found that go into more than a cursory level of explanation or detail.)

Some of the potential rationalizations that may be raised against the overall thrust of this paper can be fairly easily predicted. A likely list follows below, with brief replies. (Some of the rationalizations are revisions or defenses of prevalent current rationalizations.)


  1. The fossil record is irrelevant because we were created, rather than evolved! Evolution is nonsense!

  2. Our prehistoric ancestors were acting "against their nature" by eating meat for 2.5 million years! It's obviously maladaptive behavior!

REPLY: Both of the above have been covered in previous sections of this paper, so just a few additional brief remarks are given here.

  1. As mentioned previously, to adopt creationism solely because it supports your "lunch philosophy" is intellectually dishonest.

  2. Adaptation to a universal habit (meat-eating) is the ultimate and unavoidable result of evolution. The human genus (Homo) has gone through 3-4 separate species since its inception; this provides direct evidence of evolutionary adaptation to environmental (and universal cultural) selection pressures. Those who make claim #2 above simply have no credible evidence to support their views. Further, such claims suggest a truly massive ego on the part of the extremist; i.e., the raw/veg*n advocate supposedly knows better than all the people over 2.5 million years of evolution who ate animal foods for survival. Inasmuch as eating animal foods was clearly necessary due to ecological limits in most (and probably, for the most part, all) locations, the claim that "eating meat is maladaptive" could be restated as "survival is maladaptive." The latter statement clearly delineates the extremist ego.

RATIONALIZATION: The evidence of modern ape diets is irrelevant because we are a unique species, and we evolved in a different environment (the African savanna) than the forest-dwelling great apes.

REPLY: There is much truth in the above; the differences in human vs. ape evolution have been discussed in earlier sections. However, the significance of ape diets and the above rationalization about them stems from two points:

  1. The 180-degree about-face from previous stance on ape diets. The similarities between apes and humans have long been used to support the claim that humans are natural vegetarians. Those who have used the argument previously, and then not only drop it, but make a point of proactively targeting it for dismissal--upon hearing that the great apes are not vegetarians--are behaving inconsistently in a fashion that, again, highlights the intellectual dishonesty (perhaps not entirely conscious) implicit in such aspects of the raw/veg*n "party line."

  2. Ape diets may give insight into early evolutionary diets (pre-human). Despite the significant differences between apes and humans, the diet of apes is of some relevance as it may provide insight into the diets of the early hominids, i.e., our "early" evolutionary diet.

    The statement that we evolved on the African savanna is of interest, because plant densities are lower on the savanna, and the density of animal life higher (especially when migrating herds visit) than in the rainforest. Foley [1982] reports the surprising but very interesting information that of the three major habitats--arid regions, savanna/grasslands, and forests--the savanna habitat contains the least plant foods that are edible to humans. (It's quite surprising that an allegedly "vegetarian human" would evolve in the habitat that provides the lowest levels of plant foods!) Thus, the differences in relative availability of foods (savanna vs. rainforest) suggests that the human evolutionary diet was lower in plant foods, and higher in animal foods, than the diet of the great apes (which a number of other, separate lines of evidence also support).

RATIONALIZATION: The human gut is far too elastic for comparative anatomy to tell us anything about our natural diet.

REPLY: After years of citing the dubious analyses of gut morphology found in Fit Food for Humanity or Mills' The Comparative Anatomy of Eating, those who suddenly adopt this view when faced with contrary evidence are, again, behaving in an inconsistent and intellectually dishonest manner.

That said, although the best scientific research to date indicates we are faunivores--meat-eaters--by anatomy, it is not "hard proof." However, the gut morphology data is only one part of a large set of data (from multiple, separate lines of evidence) that points to humans being natural faunivores.

RATIONALIZATION: The evidence of comparative physiology is irrelevant:

  1. We can get adequate B-12 from unwashed produce.
  2. The low bioavailability, in plant food, of protein, iron, zinc, and EFAs is because some/all of these things are "toxic," except in tiny (nutritional) quantities.
  3. Physiological measurements made on (degenerate!) meat-eaters are invalid! Only measurements done on fruitarians are valid, and such measures will be different for "real" humans, i.e., fruitarians.

REPLY: Point #1 is common in the vegan movement; versions of points #2 and #3 above are occasionally made by fruitarian extremists. Let's briefly look at these.

  1. Insufficient evidence to support claim #1. Despite the research of Mozafar [1994] discussed earlier herein, there is insufficient data at present to support a claim that wild plant foods (alone) could provide adequate B-12 to sustain a (hypothetical) vegan gatherer tribe.

  2. This view is certainly not supported by real, honest science, though there are fruitarian extremists who present elaborate crank science "proofs" that allege protein in more than extremely modest amounts (extremely modest even by conservative estimates approved by the more mainstream conventional-vegan community) is effectively "toxic" because its metabolic by-products are allegedly toxic.

  3. Point #3 is not only speculative, it is an example of "dietary racism." Note the implicit hatred in point #3, something that, unfortunately, is far too common in the fruitarian movement (i.e., dietary racism). This view is also thoroughly egocentric as well. While it is true that levels of zinc, iron, B-12, taurine synthesis, and beta-carotene conversion will likely differ between fruitarians and non-vegetarians, without actual studies, we cannot say much about such assumed differences. This claim is basically a diversion by fruitarian extremists.


(Rationalizations in Response to the Evolutionary and Hunter-Gatherer Evidence for Omnivorous Diets)

Return to beginning of article



GO TO PART 1 - Brief Overview: What is the Relevance of Comparative Anatomical and Physiological "Proofs"?

GO TO PART 2 - Looking at Ape Diets: Myths, Realities, and Rationalizations

GO TO PART 3 - The Fossil-Record Evidence about Human Diet

GO TO PART 4 - Intelligence, Evolution of the Human Brain, and Diet

GO TO PART 5 - Limitations on Comparative Dietary Proofs

GO TO PART 6 - What Comparative Anatomy Does and Doesn't Tell Us about Human Diet

GO TO PART 7 - Insights about Human Nutrition & Digestion from Comparative Physiology

GO TO PART 8 - Further Issues in the Debate over Omnivorous vs. Vegetarian Diets

GO TO PART 9 - Conclusions: The End, or The Beginning of a New Approach to Your Diet?

Back to Research-Based Appraisals of Alternative Diet Lore

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