Natural Selection

Lizards Help Explain Survival of the Not-So-Fittest

Publication: National Geographic News   Date: November 24, 2004   View Article

Glance at a crowd at just about any big sporting event and you’ll notice that humans are a diverse bunch. Not only the fittest have survived.

Natural selection depends as much on behavior and environmental conditions as it does on physical prowess, as demonstrated by two studies of lizards in tomorrow’s issue of the journal Nature.

Beak Size Matters for Finches’ Song, Scientists Suggest

Publication: National Geographic News   Date: August 27, 2004   View Article

Darwin’s finches in Ecuador’s Galápagos Islands are cornerstones to the late British naturalist Charles Darwin’s theory of natural selection: the size and shape of the finches’ beaks are adapted to take advantage of their individual ecologic niches.

Some of the sparrow-sized songbirds have large beaks which are able to crush hard seeds—an especially useful trait in drought-prone regions. Other finches have short, sharp beaks which are good for eating insects.

Biologists Study Evolution of Animal Cooperation

Publication: National Geographic News   Date: July 9, 2003   View Article

Survival of the fittest is a simple reality in the game of life. Successful play necessarily requires a degree of selfishness, but across the animal kingdom species have evolved social behaviors. Why? Do they enhance survival?

“Many of us are really fascinated with the wide spectrum of social behavior we see across the diversity of animal taxa,” said Janis Dickinson, an evolutionary biologist at the University of California at Berkeley.

Virtual Life Forms Mutate, Shedding Light on Evolution

Publication: National Geographic News   Date: May 7, 2003   View Article

They don’t sting or bite. They don’t cause diarrhea or headaches. They don’t even exist in a tangible form. But “digital organisms”— special programs that reproduce, mutate, and adapt —can thrive inside computers, and they are teaching scientists several lifetimes worth of information about evolution.

These artificial “bugs” show that complex functions that are the digital equivalent to something like human eyesight can evolve from the simplest of functions via a long and winding road of gradual mutation, according to a team consisting of a biologist, a computer scientist, a philosopher, and a physicist.

© 2008-2010 Collected Writings By John Roach