For scientists who fear being reduced to a statistic, a theoretical physicist has some unsettling news: A single, simply calculated number provides a rough estimate of the impact of any particular scientist’s work, he says.
In a paper posted to the preprint server www.arxiv.org, Hirsch defines a researcher’s index, h, as the largest number such that the researcher has h papers with at least h citations each. For example, string theorist Edward Witten of the Institute for Advanced Study in Princeton, New Jersey, has 110 papers with 110 or more citations each, making his h index 110. The h index favors researchers who consistently produce influential papers, and disfavors those who publish many little-noted papers or just a few widely cited ones, says Hirsch (h=49): “I can’t imagine a person with a high h index who hasn’t done important work.”
This reviewer was discouraged to find out that as a new graduate student his h number is still somewhere around zero. Actually, to be honest it is zero. Thus the reviewer is dead set against such blatant numerical reductionism.
Military exercises are boosting biodiversity, according to a study of land used for US training manoeuvres in Germany. Such land has more endangered species than nearby national parks.
The land is uncultivated, but also churned up by tank tracks and explosions. This creates habitat both for species that prefer pristine lands and those that require disturbed ground, explains ecologist Steven Warren of Colorado State University in Fort Collins.
“Some people are very anti-military,” Warren says. “They assume that there’s nothing the military can do that will be beneficial, particularly with relation to ecology.” Warren, who doesn’t work for the army, used to assume the same himself. “Twenty years ago I looked at military activities as an ecologist and thought ‘they need me’. But I guess that’s not really so.”
Warren and Büttner studied several species to try and understand the benefits of military ground. One, the natterjack toad, breeds in water-filled ruts created by tank tracks, they found.
Among the other animals that were assisted by the repeated explosions were vultures and the rare mortar squirrel which lines its nest exclusively with shrapnel.
Maybe someday, if we all work together, we can turn the whole world into this kind of animal paradise.
Many experts say that scientists should get more involved in local politics — especially on school boards, where the conflicting views of scientists and advocates of intelligent design often play out. ‘Scientists have to be evangelical about explaining what science is, as well as its limitations,’ says Krauss.
To defeat your enemy, you must become the enemy, grasshopper. To defeat the evangelical, you must become the evangelical.
So what happened to the foreign DNA detected in 2000 samples? An education campaign may have deterred Oaxaca farmers from planting more GM kernels, the authors suggest. Meanwhile, offspring of the transgene-tainted plants may not have done well in southern Mexico’s mountains. Of course, it’s also possible the foreign genes were never present. Chapela offers another explanation–the team’s sampling and testing methods may have missed extremely low levels of transgenes. Otherwise, he says, ‘It’s very hard to make both [papers] compatible.’ The negative results are good news for Mexican scientists and environmentalists, who worried that genes from genetically modified corn could damage the diversity of Mexico’s native corn varieties by giving them traits that could skew their fitness. ‘The results will ease the concerns of many of us,’ says Universidad Nacional Autonoma de Mexico ecologist Jose Sarukhan–although he adds that doesn’t mean Mexico can let down its guard.
Environmentalists are concerned that the GM maize genes would damage the native corns ability to perish quickly in droughts or be devoured by ravaging insect hordes. Wow, that would just suck.
After discovering relatively little, other than basaltic lava flows, during its first six months on the Red Planet, Spirit continues to make up for lost time as it ascends Husband Hill – unearthing clues to violence in the planet’s youth.
Meanwhile, Opportunity is also experiencing a reversal of fortune on the other side of Mars. After trudging over desolate stretches of sand for about five months, it has finally reached an island of bedrock that appears unlike anything yet seen in the mission.
Spirit landed in the lava plains of Gusev Crater, getting off to a slow start in its mission. But since it began clambering up to higher ground in the Columbia Hills in July 2004, it has seen granular rocks with a mix of grain sizes. And recently it has seen the most extreme case of this from a spot about 20 metres below the summit of Husband Hill, which rises about 80 metres above the floor of Gusev Crater.
Spirit hits pay dirt…literally. We have discovered martian dirt.
I love this experimental design. If the rover should happen to discover anything that someone would want to know about, such as for instance martians or man-eating martian sand crabs, it’s flimsy construction will guarantee that it is destroyed by them. Thus, Spirit is guaranteed not to find anything interesting.
Chernobyl’s ecosystems seem to be bouncing back, 19 years after the region was blasted with radiation from the ill-fated reactor. Researchers who have surveyed the land around the old nuclear power plant in present-day Ukraine say that biodiversity is actually higher than before the disaster.
Some 100 species on the IUCN Red List of threatened species are now found in the evacuated zone, which covers more than 4,000 square kilometres in Ukraine, Belarus and Russia, says Viktor Dolin, who studies the environmental effects of radioactivity at the Ukrainian National Academy of Sciences in Kiev. Around 40 of these, including some species of bear and wolf, were not seen there before the accident.
“It’s evolution on steroids. There are a lot of deleterious mutations in species but these seem to be very quickly weeded out,” Morris explains. Many young fish living in the reactor’s cooling ponds are deformed, but adults tend to be healthy, implying that those harmed by radiation die young.
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The deleterious mutations have given way to the more successful mutations such as the squirrel with eyes that shoot laser beams and horrible bear/wolf chimeras that breath fire. Oh the wonder that is evolution!