Category Archives: science

A surprising new study published in Nature, reported by the Guardian on 12 January 2006, may help explain why Kyoto Protocol signatories Canada and New Zealand haven’t managed to reduce their greenhouse gas emissions any more effectively than nonsignatory Australia. Too many plants, not enough desert?

According to a study published today, living plants may emit almost a third of the methane entering the Earth’s atmosphere.

The result has come as a shock to climate scientists. “This is a genuinely remarkable result,” said Richard Betts of the climate change monitoring organisation the Hadley Centre. “It adds an important new piece of understanding of how plants interact with the climate.”

Methane is second only to carbon dioxide in contributing to the greenhouse effect. “For a given mass of methane, it is a stronger greenhouse gas, but the reason it is of less concern is that there’s less of it in the atmosphere,” said Dr Betts.

But the concentration of methane in the atmosphere has almost tripled in the last 150 years, mainly through human-influenced so-called biogenic sources such as the rise in rice cultivation or numbers of flatulent ruminating animals. According to previous estimates, these sources make up two-thirds of the 600m tonnes worldwide annual methane production.

Frank Keppler, of the Max Planck Institute for Nuclear Physics, who led the team behind the new research, estimated that living plants release between 60m and 240m tonnes of methane per year, based on experiments he carried out, with the largest part coming from tropical areas.

Other perplexing results:

Tree planting

Researchers in North Carolina found that planting trees to soak up carbon dioxide can suck water and nutrients from the ground, dry up streams and change the soil’s mineral balance

Aerosols

A recent study in Nature found cutting air pollution could trigger a surge in global warming. Aerosols cool the Earth by reflecting radiation back into space. Scrapping them would have adverse consequences

Global dimming

In 2003 scientists noticed levels of sunlight reaching the Earth’s surface had dropped by 20% in recent years because of air pollution and bigger, longer-lasting clouds

Fourteenth-century medicine was not without accomplishment. It could amputate limbs and normally cauterize the wounds in an effective manner. It had precious knowledge of herbal remedies for headache, minor stomachaches, menstrual cramps, and other marginal afflictions, possibly including psychological depression. But it was impotent in the face of an epidemic.

Medieval physicians still followed the theories of the second-century Greek doctor Galen, which attributed disease to imbalance in the bodily conditions, or “humours,” of an individual. The main instrument of diagnosis was eyeballing the color and consistency of urine.

The prime remedies for illnesses involved restoration of putative bodily balance through purgation (enemas) or bloodletting. Drawing blood from a sick patient was considered a credible remedy until the nineteenth century. Cleaning the bowels was thought to have a curative effect. Enemas are still a popular home remedy. Nineteenth-century medicine introduced antiseptic surgery and anesthesia and smallpox inoculation but in the face of a pandemic outbreak was not much better off than the physicians of fourteenth-century England.

Faced with a worldwide outbreak of what was arbitrarily called Spanish influenza in 1918, which killed fifty million people within a year, the early twentieth-century medical profession was not much more effective in terms of diagnosis and cure than its medieval counterpart facing the Black Death. Essentially the flu pandemic of 1918 came and went without anyone knowing why, in spite of the capacity to see under a microscope some viruses and bacteria that were totally invisible to the physicians of the fourteenth century.

SOURCE: In the Wake of the Plague: The Black Death & the World It Made, by Norman F. Cantor (Harper Perennial, 2002), pp. 9-10

Cantor is no Tuchman, but I’ll see if I can find a few passages to excerpt, even if I have to rearrange them to counteract the author’s tendency to ramble about.

Marginal Revolution‘s Tyler Cowen is for the birds:

… behavioral studies in recent years have proved that many birds have more pallium power than your average mammal.

Even seemingly moronic pigeons can categorize objects as “human-made” vs. “natural”; discriminate between cubistic and impressionistic styles of painting; and communicate using visual symbols on computers, according to evidence compiled by the consortium, which spent seven years on the project with input from scientists around the world.

Some birds can play games in which they intentionally tell lies. New Caledonian crows design and make tools. Scrub jays can recall events from specific times or places — a trait once thought unique to humans. And perhaps most impressive, parrots, hummingbirds and thousands of other species of songbirds are able to teach and learn vocal communication — the basic skill that makes human language possible. That’s a variant of social intelligence not found in any mammal other than people, bats, and cetaceans such as dolphins and whales.

Bats? Brainy as a bat? Whoa!