Sunday, January 2, 2011

More quotes from Jerry Coyne

One answer is religion. Unlike germ theory, the idea of evolution strikes at the heart of human ego, suggesting that we were not the special object of God's attention but were made by the same blind and mindless process of natural selection that also built ferns, fish and rabbits. Another answer is ignorance: most Americans are simply unaware of the multifarious evidence that makes evolution more than "just a theory," and don't even realize that a scientific theory is far more than idle speculation.

One of my favorite cases of embryological evidence for evolution is the furry human fetus. We are famously known as "naked apes" because, unlike other primates, we don't have a thick coat of hair. But in fact for one brief period we do--as embryos. Around sixth months after conception, we become completely covered with a fine, downy coat of hair called lanugo. Lanugo is usually shed about a month before birth, when it's replaced by the more sparsely distributed hair with which we're born. (Premature infants, however, are sometimes born with lanugo, which soon falls off.) Now, there's no need for a human embryo to have a transitory coat of hair. After all, it's a cozy 98.6 degrees Fahrenheit in the womb. Lanugo can be explained only as a remnant of our primate ancestry: fetal monkeys also develop a coat of hair at about the same stage of development. Their hair, however, doesn't fall out, but hangs on to become the adult coat. And, like humans, fetal whales also have lanugo, a remnant of when their ancestors lived on land.

Many more quotes from Jerry Coyne's Why Evolution is True can be found at Some stuff I stole from Jerry Coyne's Why Evolution is True.

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