Letters from the April 22, 2006, issue of Science News

Second cousins

With reference to “Chimps creep closer yet” (SN: 2/11/06, p. 94), some scientists say that bonobos are genetically closer to humans than to chimps. How did they compare in the referenced study?

Dick Medvick
Cleveland Heights, Ohio

Bonobos are indeed as genetically close to humans as are chimps, but there wasn’t enough genomic data available for bonobos to include them in the study, says evolutionary biologist Soojin Yi of the Georgia Institute of Technology.—C. Gramling

Why me?

Some of the descriptions about confusion of self (“Self-Serve Brains: Personal identity veers to the right hemisphere,” SN: 2/11/06, p. 90) were very reminiscent of the confusion I often sense in dreams. I even recognize in some dreams the sensation described in the article about various body parts not being part of “me.” I wonder if this aspect of normal (I assume) dreaming has been investigated.

Stanley E. Anderson

Westminster, Calif.

It surprises me that none of the researchers mentioned in your article considered the possibility that the essential sense of self is an extremely primitive aspect of brain function. An animal could not protect itself from predators or physical dangers unless it had a well-developed sense of personal being.

Alex Heydon
Ajax, Ontario

Researcher Todd Feinberg of Beth Israel Medical Center in New York raises the possibility that disordered selves represent a kind of “waking dream” in his book Altered Ego: How the Brain Creates the Self (2001, Oxford Univ. Press, New York). Feinberg argues that a primitive sense of self occurs in many animals.—B. Bower

Think thin

So, researchers studying the effects of the hunger hormone ghrelin have found that hungry mice do better on tests of learning and memory (“Hunger for Knowledge: Appetite hormone may stimulate memory,” SN: 2/25/06, p. 118). Four hundred years ago, William Shakespeare had Julius Caesar say, in Act I, Scene II, “Let me have men about me that are fat; Sleek-headed men and such as sleep o’ nights. Yon Cassius has a lean and hungry look; He thinks too much. …”

Merle Hetley
Bangor, Maine