Ref Cost of "intelligence"

[Diane]

Finally, a paper, open access, with a citation pointing toward all those factoids about the brain:
Cooperation and the evolution of intelligence

Abstract:

The high levels of intelligence seen in humans, other primates, certain cetaceans and birds remain a major puzzle for evolutionary biologists, anthropologists and psychologists. It has long been held that social interactions provide the selection pressures necessary for the evolution of advanced cognitive abilities (the ‘social intelligence hypothesis’), and in recent years decision-making in the context of cooperative social interactions has been conjectured to be of particular importance. Here we use an artificial neural network model to show that selection for efficient decision-making in cooperative dilemmas can give rise to selection pressures for greater cognitive abilities, and that intelligent strategies can themselves select for greater intelligence, leading to a Machiavellian arms race. Our results provide mechanistic support for the social intelligence hypothesis, highlight the potential importance of cooperative behaviour in the evolution of intelligence and may help us to explain the distribution of cooperation with intelligence across taxa.

Excerpt:

Natural selection never favours excess; if a lower-cost solution is present, it is selected for. Intelligence is a hugely costly trait. The human brain is responsible for 25 per cent of total glucose use, 20 per cent of oxygen use and 15 per cent of our total cardiac output, although making up only 2 per cent of our total body weight [1]. Explaining the evolution of such a costly trait has been a long-standing goal in evolutionary biology, leading to a rich array of explanatory hypotheses, ranging from evasion of predators to intelligence acting as an adaptation for the evolution of culture [2–4]. Among the proposed explanations, arguably the most influential has been the ‘social intelligence hypothesis’, which posits that it is the varied demands of social interactions that have led to advanced intelligence [4–12].

1. Clarke D. D., Sokoloff L. 1999 Circulation and energy metabolism. In Basic neurochemistry: molecular, cellular and medical aspects (eds Siegel G. J., Agranoff B. W., Albers R. W., Fisher S. K., Uhler M. D.), pp. 637–670. Philadelphia, PA: Lippincott-Raven.

[Barrett Dorko]

Diane,

This tracks perfectly with several contentions commonly expressed here. I heard Ginger Campbell say recently that "conscious processes are expensive." I assume this means that our default mode will be to use unconscious ones.

There's also this: Recently a PT with a web site extolling his virtues and expertise told me that the regular contributors on Soma Simple were "too smart for me" and thus he refused to ever say anything. I think he meant this as a compliment but I didn't take it that way.

[Diane]

Posting another one : http://www.sciencemag.org/content/336/6078/161.full
Revitalizing Remyelination—the Answer Is Circulating
Stephanie A. Redmond and Jonah R. Chan
Science 13 April 2012: 161-162.

[gollygosh]

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Originally Posted by Barrett Dorko

There's also this: Recently a PT with a web site extolling his virtues and expertise told me that the regular contributors on Soma Simple were "too smart for me" and thus he refused to ever say anything. I think he meant this as a compliment but I didn't take it that way.

I've got to admit to being pretty much in awe of the knowlege on this site. But you all are pretty patient with attempts to participate.

Geralyn

[Diane]

Originally Posted by Diane

1. Clarke D. D., Sokoloff L. 1999 Circulation and energy metabolism. In Basic neurochemistry: molecular, cellular and medical aspects (eds Siegel G. J., Agranoff B. W., Albers R. W., Fisher S. K., Uhler M. D.), pp. 637–670. Philadelphia, PA: Lippincott-Raven.

This book is brill. I'm going to get it.
It's available at NIH; they don't let you browse through, but you can search specific pages.

It explains so much about how/why the brain is qualitatively different from every other kind of tissue in the body. The brain has to run like crazy the whole time it's alive, or the entire organism croaks.

I just ordered it. I think this book might be the one I've looked for all my life. It's in its 7th ed. now. The reference came from the 1999 edition. This one is from 2006.

[Diane]

Check it out.