PAUL BENTZEN
Starting in the late 1970s, aspiring evolutionary biologist David Reznick became intent on documenting evolution in action. Although he had learned in school that observable change took place over millennia, the young biologist questioned that notion, and set out to observe genetic adaptation in real time. “Prominent evolutionary biologists were skeptical you could see it happening,” Reznick recalls. “I guess it was a gamble, but it seemed like one that was worth taking.”
He chose Trinidadian guppies as his study system, and as a graduate student at the University of Pennsylvania Reznick flew to the Caribbean island off the north coast of Venezuela in 1978 to observe and collect guppies, and again in 1981 to shuffle the fish between streams. He moved guppies that were ...
