adult human ~20-25: other primates 8-10: other (non-primate) mammals 3-5 %
||Leonard WR, Robertson ML, Snodgrass JJ, Kuzawa CW. Metabolic correlates of hominid brain evolution. Comp Biochem Physiol A Mol Integr Physiol. 2003 Sep136(1):5-15 p.5 right column top paragraphPubMed ID14527625
||W.R Leonard, M.L Robertson Evolutionary perspectives on human nutrition: the influence of brain and body size on diet and metabolism Am. J. Hum. Biol., 6 (1994), pp. 77-88 doi: 10.1002/ajhb.1310060111PubMed ID28548424
||P.5 left column: "From the perspective of comparative physiology and nutrition, what is extraordinary about the large brains of humans is their high metabolic cost. Brain tissue has very high energy demands per unit weight, roughly 16 times greater than those of muscle tissue (BNID 113753). Yet, despite the fact that humans have much larger brains per body weight than other terrestrial mammals, the total (resting) energy demands for the human body are no more than for any other mammal of the same size (Leonard and Robertson, 1992, & primary source). The consequence of this paradox is that humans allocate a much larger share of their daily energy budget to ‘feed their brains’. Brain metabolism accounts for ∼20–25% of resting energy demands in an adult human body. This is far more than the 8–10% observed in other primate species, and still more than the 3–5% allocated to the brain by other (non-primate) mammals (primary source)."