Interesting Carl Zimmer piece in the NY Times today. Looks like human tissue metabolism is drastically different from animal tissue metabolism in exactly two areas: our prefrontal cortex, and our muscles.

Hypothesis #1 says that we robbed Peter to pay Paul . . . we crippled our own muscle strength (pound for pound) to free up more energy for our expanded prefrontal cortex. Hypothesis #2, (end of the article) folds this new info into the existing "endurance runner" hypothesis, suggesting that perhaps we swapped out strong muscle for endurance muscle instead. Which would mean we put those freed up STR points into CON instead.

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