American Scientist

Doubts Arise About a Rare Woodpecker

The ivory-billed woodpecker was considered extinct until it flapped back onto the scene, blurrily, in a controversial videotape shot in an Arkansas swamp in 2004. The bird's resurrection made national news and became a symbolic victory for conservationists, with a paper in Science and $10 million in federal money to support its struggling resurgence. It's an inspiring story, but it may be founded in error, some experts now say. David A. Sibley, the nation's best-known birder, and three colleagues have published a technical comment in Science saying that the videotaped bird is, in fact, the common pileated woodpecker. A rebuttal from lead author of the discovery paper, John Fitzpatrick of the Cornell Lab of Ornithology, argues that Sibley's critique contains errors.

Sibley, D. A., et al. Comment on "Ivory-billed Woodpecker (Campephilus principalis) Persists in Continental North America." Science 311:1555 (March 17, 2006)

Genetic Experiment Produces an Effective Vaccine Against an African Killer

Deadlier even than Ebola, the Marburg virus killed more than 90 percent of those it infected last year in Angola—more than 300 people in all. But now medical researchers have created a vaccine that has proven unusually effective in monkeys. The research team removed one gene from a harmless vesicular stomatitis virus and replaced it with a key gene from Marburg. Monkeys that were infected with Marburg and then given the vaccine stayed healthy. Those denied the vaccine died in 10 to 12 days.

Daddario-DiCaprio, K. M., et al. Postexposure protection against Marburghaemorrhagic fever with recombinant vesicular stomatitis virus vectors in non-human primates: an efficacy assessment. The Lancet 367:1399-1404 (April 29, 2006)

Another Spot Turns Red

An enormous tempest has appeared on Jupiter, creating a smaller version of the famous Great Red Spot, a storm large enough to swallow three Earths that has raged for 300 years. The new storm, known as "Red Spot Jr.," has been brewing since about 1915, but a surprising development took place last year—it turned red, possibly because it was drawing material from deep in Jupiter's atmosphere.

http://hubblesite.org/newscenter/newsdesk/archive/releases/2006/19/

Brains of the Brightest Kids Are Built Later

The brains of the smartest kids develop differently from those of normal children. That's not a surprise. But whereas scientists had expected to see differences in brain size or shape, a brain-mapping study instead revealed divergence in the timing of brain growth. A hallmark of genius, it turns out, is not early brain development; instead, the period of peak wiring in the kids with the highest IQs at age 11 or 12 seems to lag behind average children by about four years—although it does last longer.

Shaw, P., et al. Intellectual ability and cortical development in children and adolescents. Nature 440:676-679 (March 30, 2006)

A Long-Sought Fish Crawls to Light

Paleobiologists have long sought the "missing link" between ancient fish and land animals. Now they think they've discovered the perfect intermediary, a species dubbed Tiktaalik roseae, which roamed Earth during the Late Devonian, 385 million to 359 million years ago. Scientists described fossil specimens that show the beginnings of digits, wrists, elbows and shoulders, as well as skulls, necks and ribs that prefigure those of tetrapods like today's familiar four-legged land animals.

Shubin, N., et al. The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb. Nature 440:764-771 (April 6, 2006)

Rivers Beneath Thick Ice Complicate Study of Extremophiles

The discovery of a network of rivers far beneath the icy surface of Antarctica calls into question the notion that microbial life forms thought to be living in Antarctica's vast sub-glacial lakes must have evolved in isolation for perhaps millions of years. That feature of this uniquely harsh environment was an important justification for drilling deep down into Lake Vostok to sample the water for microbes. Now the rationale is less clear.

Wingham, D. J., et al. Rapid discharge connects Antarctic subglacial lakes. Nature 440:1033-1036 (April 20, 2006)

Starlings Reveal Surprising Linguistic Sophistication

Linguists had long believed that only humans can learn more sophisticated types of grammar, for example by recognizing "clauses" in longer utterances. In an experiment conducted two years ago, a group of tamarin monkeys failed to do so, seemingly validating linguist Noam Chomsky's theory that such grammar is unique to humans. But in a new study, 9 of 11 starlings learned to spot inserted phrases at least 90 percent of the time, identifying the special utterances by pecking buttons in exchange for food.

Gentner, T. Q., et al. Recursive syntactic pattern learning by songbirds. Nature 440:1204-1207 (April 27, 2006)

Studies Supporting Moderate Drinking May Have Goofed

Many studies have shown that teetotalers have greater risk of coronary heart disease than do moderate drinkers. But most of those studies included as abstainers people who had been forced to quit drinking, usually because of declining health or old age—a subset that may have biased the results. This methodological flaw was first noticed in 1988, but it mars even the latest research on the subject. Of the 54 different studies that were recently examined, only seven correctly considered former drinkers differently from abstainers.

Fillmore, K. M., et al. Moderate alcohol use and reduced mortality risk: Systematic error in prospective studies. Addiction Research and Theory, preview article