Discover, September 30, 1998

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In the early 1950s, when biologist John Tyler Bonner was just beginning his career at Princeton, he was startled one day to receive a message from Albert Einstein, who worked at the nearby Institute for Advanced Study. Einstein wanted Bonner to come to his office and show him a movie.

The film that Einstein was so eager to see starred an amoeba named Dictyostelium. Normally, this single-celled organism goes about its quiet business of hunting down, engulfing, and digesting bacteria that live in soil. After gorging itself sufficiently, Dictyostelium divides in two, and the new pair go their separate, bacteria-devouring ways.

Continue reading “The slime alternative” →

Discover, August 1, 1998

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Justin Kalesto doesn’t want to wake up. A woman is calling his name, but he turns his head deeper into his pillow. He is 12 years old, and from Mangbangau, a village deep in remote southern Sudan. He wears a tattered pair of blue shorts and a thin necklace of blue beads; on the windowsill above his cot are his sandals and woven basket. Justin’s sunken abdomen curves inward like a bowl; his nostrils are clogged with bacteria and dried mucus, and the skin around his closed eyes puffs out, giving him the face of a frog.

Continue reading “A Sleeping Storm” →

Discover, July 31, 1998

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If you find yourself in prairie dog country, you may notice that one opening to their burrows is always built up a few inches aboveground. There’s a very good reason for this: thanks to the quirks of fluid dynamics, the higher aboveground you are, the faster the wind blows. This means that the air moving over the raised opening is at higher pressure than that moving over the other entrance, and since high pressure always flows to low, a cool breeze is pushed through the burrow. The prairie dogs get fresh air without using a single watt to power a fan or an air conditioner.

Continue reading “Cats’ Paws and Catapults” →

Discover, June 1, 1998

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There are two basic points of view on global warming: it’s a problem or it’s not. In most of the world that argument is over and the pessimists have won, but not in the United States. And yet politically, if not scientifically, the argument seemed to be settled long ago—on October 15, 1992, to be precise, when the United States became the fourth country, after Mauritius, the Seychelles, and the Marshall Islands, to ratify the United Nations Framework Convention on Climate Change. George Bush had signed the treaty at Rio de Janeiro four months earlier. It committed us to an objective: Stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.

Continue reading “Carbon Cuts and Techno-Fixes” →

Discover, June 1, 1998

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For 139 years, ever since its delicate bones and feathers were found splayed on a limestone slab in a German quarry, Archaeopteryx has had the distinction of being the most primitive bird known. Its clawed wings, toothy beak, and long bony tail, most paleontologists now believe, show the transformation of a lineage of bipedal dinosaurs into birds. Since its discovery, the 145-million-year-old Archaeopteryx has perched alone on a low branch of the avian evolutionary tree. Now the old bird finally has company. In March, paleontologists described a 65- to 70-million-year-old bird from Madagascar, which, though younger than Archaeopteryx, is almost as primitive. In life it would have resembled a little winged Velociraptor.

Continue reading “Evolution Watch: A Sickle in the Clouds” →