Paleo diets are all the rage, with new Paleo-focused books and articles appearing every day.

Unlike many diet fads, the Paleo plan – low in carbs but rich in protein, animal fats, fruits, and vegetables – meets the scientific test.

The Paleo diet's predecessor – the Atkins diet – was on the right track, but was overly meat-focused, under-emphasized colorful produce, and made little distinction among types of fats.

Dr. Atkins was right to exonerate saturated animal fats as a driver of heart disease … but he failed to stress the advantages of seafood as people's major protein source.

Scientists keep unearthing evidence that early humans and their immediate evolutionary predecessors got much of their protein and fat from omega-3-rich aquatic animals like crabs, turtles, frogs, snails, and fish. 

Easy access to small water-dwellers would have let early humans get ample protein in their diets without risk of injury from large prey or competing carnivores like hyenas and lions.

Access to easily harvested aquatic foods would have attracted pre-humans and humans to streams, lakes, rivers, and oceans.

As renowned brain researcher Michael Crawford, Ph.D., points out, the Olduvai Gorge where Mary and Louis Leaky found the earliest hominid remains was the Olduvai River when pre-humans lived there.

He's co-authored several peer-reviewed scientific papers examining the evidence that early humans and their ancestors ate Paleo diets rich in aquatic foods (see our list of sources, below).

By providing omega-3s in abundance, Paleo diets rich in aquatic foods could have fueled the explosion in brain size and intelligence that divides us from our pre-human ancestors.

The human brain is rich in fats, but omega-3 DHA is the most abundant by far. DHA is needed for the brain's basic functions … and this omega-3 abounds only in fish, shellfish, and other aquatic foods.

For more on the exciting evidence linking aquatic diets to the rapid emergence of our own remarkably big-brained species, see “Did Humans Evolve on Fishy Diets?”, “Omega-3 Brain Evolution Theory Gets a Boost”, and “Were Human Ancestors Aquatic Apes?”. 

Ancient paleo people: a brief primer
Archeology and molecular biology alike suggest that modern humans (Homo sapiens) diverged from a common hominid ancestor about 200,000 years ago.

Persuasive evidence suggests that all modern people inherited their mitochondrial DNA from a woman – nicknamed “Mitochondrial Eve” – who lived in Africa about 160,000 years ago.

And it appears that all modern men inherited their Y chromosomes from a man – called “Y-chromosomal Adam” – who lived 140,000–500,000 years ago, also in Africa.

The earliest known offshoots of Mitochondrial Eve are the hunter-gatherers of Southern Africa known as the Khoesan, who now live in the semi-desert regions of Namibia and Botswana.

Archeological, historical, and genetic evidence suggests that these hunter-gatherers included marine-foraging people of Africa's southern and eastern coasts.

Now, African, German, and American researchers report an exciting new finding … one that seems to support the idea that humans evolved on diets dominated by omega-3-rich aquatic animals.

Man with very ancient DNA lived off ocean foods
Four years ago, Professor Andrew Smith of the University of Cape Town discovered a skeleton at the southern tip of Africa … the same region where modern humans originated some 200,000 years ago.

The man's 2,330-year-old skeleton was also very close to the site where 117,000-year-old human footprints – dubbed “Eve's footprints” – had earlier been found.

The man's skeleton was examined by Professor Alan Morris from the University of Cape Town, who concluded that the man was a “marine forager” who subsisted on shellfish.

A bony growth in his ear canal – known as “surfer's ear” – suggested that he frequently dove for food in the cold coastal waters.

And shells carbon-dated to the same period were found near his grave, which confirmed his seafood diet. 

What can DNA from the skeleton of a man who lived 2,330 years ago tell us about ourselves?

When his DNA profile is one of the “earliest diverged” – that is, one of the oldest in genetic terms – the answer is “a great deal”.

Knowing that the man's DNA needed to be examined, Professor Morris contacted Professor Vanessa Hayes, a world-renowned expert in African genomes.

Dr. Hayes set out to sequence the man's maternal or mitochondrial DNA to provide clues to early modern human prehistory and evolution.

However, the acidity of the soil in the region makes it hard to acquire DNA from skeletons. So she called on famed paleo-geneticist Svante Pääbo … the first scientist to successfully sequence the DNA of a Neanderthal.

Professor Pääbo's team generated a complete mitochondrial genome, using DNA extracted from the man's tooth and rib.

The findings provided DNA evidence that this man and his fellow coastal dwellers were the humans most closely related to “Mitochondrial Eve”.

Why does this finding matter?
This is the first genomic evidence that the Southern African hunter-gatherers who carry the earliest modern human lineages ate Paleo-style diets rich in ocean foods.

While this doesn't prove that humans evolved on a diet high in aquatic foods, it lends that hypothesis substantial support.

Together with the evidence mentioned above, this new finding supports the idea that Paleo diets rich in omega-3s fueled the evolution of modern humans from pre-human ancestors.

And it means that folks who plan to follow a Paleo diet should consider two things.

First, diets rich in seafood are clearly good for brain, heart, eye, and overall health.

And growing evidence suggests that the original Paleo diet probably provided as much or more aquatic foods than meat.

  • Arizona State University (ASU). ASU team detects earliest modern humans. Accessed online October 20, 2007 at
  • Blasco R. Human consumption of tortoises at level IV of Bolomor Cave (Valencia, Spain) J Archaeol Sci. 2008;35:2839–2848. 
  • Braun DR et al. Early hominin diet included diverse terrestrial and aquatic animals 1.95 Ma in East Turkana, Kenya. PNAS June 1, 2010 vol. 107 no. 22 10002-10007. doi: 10.1073/pnas.1002181107
  • Broadhurst CL, Cunnane SC, Crawford MA. Rift Valley lake fish and shellfish provided brain-specific nutrition for early Homo. Br J Nutr. 1998;79:3–21. 
  • Broadhurst CL, Wang Y, Crawford MA, Cunnane SC, Parkington JE, Schmidt WF. Brain-specific lipids from marine, lacustrine, or terrestrial food resources: potential impact on early African Homo sapiens. Comp Biochem Physiol B Biochem Mol Biol. 2002 Apr;131(4):653-73. Review.
  • Crawford MA, Bloom M, Broadhurst CL, Schmidt WF, Cunnane SC, Galli C, Gehbremeskel K, Linseisen F, Lloyd-Smith J, Parkington J. Evidence for the unique function of docosahexaenoic acid during the evolution of the modern hominid brain. Lipids. 1999;34 Suppl:S39-47. Review.
  • Crawford MA, Broadhurst CL, Guest M, Nagar A, Wang Y, Ghebremeskel K, Schmidt WF. A quantum theory for the irreplaceable role of docosahexaenoic acid in neural cell signalling throughout evolution. Prostaglandins Leukot Essent Fatty Acids. 2013 Jan;88(1):5-13. doi: 10.1016/j.plefa.2012.08.005. Epub 2012 Nov 30.
    Crawford MA, Broadhurst CL. The role of docosahexaenoic and the marine food web as determinants of evolution and hominid brain development: the challenge for human sustainability. Nutr Health. 2012 Jan;21(1):17-39. doi: 10.1177/0260106012437550.Cunnane SC, Crawford MA. Survival of the fattest: fat babies were the key to evolution of the large human brain. Comp Biochem Physiol A Mol Integr Physiol. 2003 Sep;136(1):17-26. Review.
  • Cunnane SC. [Survival of the fattest: the key to human brain evolution]. Med Sci (Paris). 2006 Jun-Jul;22(6-7):659-63. Review. French.
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  • Garvan Institute of Medical Research (GIMR). Ancient human genome from southern Africa throws light on our origins. September 29, 2014. Accessed at
  • George Washington University (GWU). Archeologists Discover “Brain Food” in Early Human Ancestors' Diet. May 28, 2010. Accessed at
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  • Minkel JR. Earliest Known Seafood Dinner Discovered: Dished out with a side of symbolic thought. Scientific American, October 17, 2007. Accessed online October 20, 2007 at
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  • Wong K. Food for Thought: Giant Hominid teeth not for crunching nuts, but shellfish. Scientific American, February 13, 2006. Accessed online October 20, 2007 at