Evolution

As Dawkins (1976) pointed out, when he introduced the concept of the meme as a cultural item that gets itself copied, the fundamental principle of biology is that all life evolves by the differential survival of replicating entities. . . . Two

If there were alternate structures that preserved the information, evolution would continue　unimpeded. This claim can be further examined in yet another intuition pump. Imagine that on another　planet, “odd-numbered” generations used the DNA rungs A, C, G, and T, and “even-numbered” generations used

In his book Le Ton Beau de Marot , Doug Hofstadter (1997) draws attention to the role of what he calls spontaneous intrusions into a creative process. In the real world, almost everything that happens leaves a wake, makes shadows, has an

Suppose Dr. Frankenstein designs and constructs a monster, Spakesheare, which thereupon sits up and writes out a play, Spamlet. Who is the author of Spamlet? To a Darwinian, this new element in the cascade of cranes is simply the latest in a

It showed that the frog’s visual system is sensitive to small moving dark spots on the retina, tiny shadows cast in almost all natural circumstances by flies flying in the vicinity. This “fly-detector” mechanism is appropriately wired to the hair trigger in

In 1988, Otto Neugebauer, the great historian of astronomy, was sent a photograph of a fragment of Greek papyrus that had a few numbers written in a column on it. The sender, a classicist, had no clue about the meaning of this

Everybody knows about the familiar large-scale cycles of nature: day follows night follows day; summer-fall-winter-spring-summer-fall-winter-spring; the water cycle of evaporation and precipitation that refills our lakes, scours our rivers, and restores the water supply of every living thing on the planet. But

A woman in New York City may suddenly acquire the property of being a widow by virtue of the effects that a bullet has just had on some man’s brain in Dodge City, over a thousand miles away. (In the days of

You may think you’re a mammal, and that dogs and cows and whales are mammals, but really there aren’t any mammals at all. There couldn’t be! Here’s a philosophical argument to prove it. 1. Every mammal has a mammal for a mother.

A curious feature of evolution by natural selection is that it depends crucially on events that “almost　never” happen. For instance, speciation, the process in which a new species is generated by wandering away from its parent species, is an exceedingly rare event,