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    Like Being Human? Thank Meat
    By News Staff | October 4th 2012 10:11 AM | 5 comments | Print | E-mail | Track Comments
    A skull fragment unearthed in Tanzania verifies that our ancient ancestors were eating meat at least 1,500,000 years ago and that can tell us something about the evolution of human physiology and brain development and why we wouldn't be where we are if there was a Prehistoric PETA.

    The two-inch skull fragment was found at the famed Olduvai Gorge in northern Tanzania, a site that for decades has yielded numerous clues into the evolution of modern humans and is sometimes called `the cradle of mankind.'

    The fragment belonged to a 2-year-old child and showed signs of porotic hyperostosis associated with anemia. According to the study, the condition was likely caused by a diet suddenly lacking in meat.
    The evidence showed that the juvenile's diet was deficient in vitamin B12 and B9. Meat seems to have been cut off during the weaning process so he was not getting the proper nutrients and probably died of malnutrition.  Nutritional deficiencies such as anemia are most common at weaning, when children's diets change drastically. The authors suggest that the child may have died at a period when he or she was starting to eat solid foods lacking meat. Alternatively, if the child still depended on the mother's milk, the mother may have been nutritionally deficient for lack of meat.

    The analysis offers insights into the evolution of hominins including Homo sapiens. The movement from a scavenger, largely plant-eating lifestyle to a meat-eating one may have provided the protein needed to grow our brains and give us an evolutionary boost.

    A long-standing claim is that we became human when we became carnivorous-omnivorous creatures.
    "Meat eating has always been considered one of the things that made us human, with the protein contributing to the growth of our brains," said Charles Musiba, Ph.D., associate professor of anthropology at the University of Colorado Denver. "Our work shows that 1.5 million years ago we were not opportunistic meat eaters, we were actively hunting and eating meat. Meat eating is associated with brain development. The brain is a large organ and requires a lot of energy. We are beginning to think more about the relationship between brain expansion and a high protein diet."


    Fragment of a child's skull discovered at Olduvai Gorge, Tanzania, shows the oldest known evidence of anemia caused by a nutritional deficiency. Credit: Citation: Dominguez-Rodrigo M, Pickering TR, Diez-Martin F, Mabulla A, Musiba C, et al. (2012) Earliest Porotic Hyperostosis on a 1.5-Million-Year-Old Hominin,Olduvai Gorge, Tanzania. PLoS ONE 7(10): e46414. doi:10.1371/journal.pone.0046414

    Previous reports showed that early hominids ate meat, but whether it was a regular part of their diet or only consumed sporadically was not certain. The authors suggest that the bone lesions present in this skull fragment provide support for the idea that meat-eating was common enough that not consuming it could lead to anemia.

    Humans are one of the few surviving species with such a large brain to body size ratio. Chimpanzees, our closest relatives, eat little meat and have far less brain capacity than humans,  which separates us from our distant cousins. "The question is what triggered our meat eating? Was it a changing environment? Was it the expansion of the brain itself? We don't really know."

    "The presence of anemia-induced porotic hyperostosis…indicates indirectly that by at least the early Pleistocene meat had become so essential to proper hominin functioning that its paucity or lack led to deleterious pathological conditions," the study said. "Because fossils of very young hominin children are so rare in the early Pleistocene fossil record of East Africa, the occurrence of porotic hyperostosis in one…suggests we have only scratched the surface in our understanding of nutrition and health in ancestral populations of the deep past."

    Citation: 
    Manuel Domínguez-Rodrigo, Travis Rayne Pickering, Fernando Diez-Martín, Audax Mabulla, Charles Musiba, Gonzalo Trancho, Enrique Baquedano, Henry T. Bunn, Doris Barboni, Manuel Santonja, David Uribelarrea, Gail M. Ashley, María del Sol Martínez-Ávila, Rebeca Barba, Agness Gidna, José Yravedra, Carmen Arriaza, 'Earliest Porotic Hyperostosis on a 1.5-Million-Year-Old Hominin, Olduvai Gorge, Tanzania', PLoS ONE 7(10): e46414. doi:10.1371/journal.pone.0046414

    Comments

    No doubt, meat's a great way to get nutrition, especially for primates and cave men. A well balanced vegetarian diet might even be better, but probably not available to cave men.

    But, so, why don't modern vegetarian children all die of malnutrition?

    Just an FYI: Dr. Debra Martin and I, both paleopathologists, have commented formally on this research via PLOS ONE in the style of a traditional Letter to the Editor.

    You can read it here: http://www.plosone.org/annotation/listThread.action?root=55385

    We hope this debate generates further research and we look forward to greater understandings of the evolution of diet in the future!

    John Crandall, MA
    University of Nevada, Las Vegas

    This trots out a lot of old science that is now somewhat disproven. While clearly many hominid and hominin lines ate meat, there is zero evidence that this led to our brains' size increase. Zero. Think about this: if eating meat *causes* larger brains over time, then why do all carnivores have brains barely larger than their prey? And as another commenter pointed out, why are modern vegetarian and vegan babies not dropping dead, and why are they not growing up with horrible anemia? Andreas Cahling became a Mr. Universe as a vegan, so clearly there has to be much more to our evolution than turning to meat consumption over the diets of our modern kin, the chimps, bonobos, both types of gorilla, and the orangutans. Our brains are significantly larger due to selection events acting on mutations unique to our line. Trying to say more than that is simply trying to justify a modern "Standard American Diet" by slanting bad science. "Thank meat," and bringing up PETA as if caring about animals would have prevented our evolution, and the generally hostile tone toward modern vegetarians point to an unscientific axe to grind. If you do not wish to be vegetarian, then don't do it; we will not force you to care for animals, for your own health, and for the welfare of our planet. If you do not want a lecture, then mind your tone. Caring about the emotional importance of others outside of our own kind, aka "empathy," is developed to a highly unique level in humans, to the point where we even try to empathise with the spirits of the dead, forces of Nature, and various deities, none of which we can see or prove are there as intelligent entities (the not-so-fine arts known as Religion and Spirituality).

    Hank
    , why are modern vegetarian and vegan babies not dropping dead,
    Vegan babies do drop dead.  If any state in the USA finds out you have a baby on a vegan diet, your kid will be in foster care.
    Gerhard Adam
    Andreas Cahling became a Mr. Universe as a vegan, so clearly there has to be much more to our evolution than turning to meat consumption ...
    Interesting story, except that it isn't true.
    I also believe in very little animal protein, other than some raw milk products. I also believe in taking goat's milk, since it is more easily used by the human body. Beef is totally taboo, since it is loaded with saturated fats, uric acid and chemicals from the steroids farmers feed their cattle.
    http://bodybuilding_workout.home.insightbb.com/trainingarticles/andreascahling/
    Andreas Cahling disclosed his diet: "One of the staples of my diet is grilled cheese sandwiches.  I take one slice of heavy, whole grain bread and slap on a thick slab of raw goat cheese.  Then I lightly toast this in the oven to melt the cheese into the bread.  I might eat four or five of these open-faced sandwiches per day."
    http://www.dynamicbodies.com/vegetari.htm
    Mundus vult decipi