バッタ大量発生予報

メディア：WSJ
主題：Day of the Grasshopper Looms
副題：Western Farmers, Ranchers Worry an Expected Infestation Could Ravage Crops


（張付け開始）
By STEPHANIE SIMON

DENVER—Farmers and ranchers across the West are bracing for a grasshopper infestation that could devastate millions of acres of crops and grazing land.

Over the coming weeks, federal officials say, grasshoppers will likely hatch in bigger numbers than any year since 1985. Hungry swarms caused hundreds of millions of dollars in damage that year when they devoured corn, barley, alfalfa, beets—even fence posts and the paint off the sides of barns.

A federal survey of 17 states taken last fall found critically high numbers of adult grasshoppers in parts of Idaho, Montana, Nebraska, South Dakota and Wyoming. Each mature female lays hundreds of eggs. So "the population could be very, very high this year," said Charles Brown, who manages grasshopper suppression for the U.S. Department of Agriculture.

Ryan Fieldgrove is dreading the influx.

A rancher near Buffalo, Wyo., Mr. Fieldgrove was enjoying a banner year last summer when, seemingly out of nowhere, crawling carpets of hoppers marched onto his rangeland—a harbinger of this year's infestation. In three weeks, they had eaten every blade of tender, nutritious grass on his 10,000 acres. They also ate his wife's lilac bushes. "They took it all," Mr. Fieldgrove said.

Unable to find enough grass, Mr. Fieldgrove's 200 young calves began to lose weight. He ended up selling them at auction several weeks earlier—and 60 pounds per calf lighter—than planned. And he had to import hay to feed the mother cows he kept on his ranch for the winter.

The grasshoppers cost Mr. Fieldgrove about $30,000 in profit, he said—and local agricultural officials are warning him it could be worse this year.

To try to get ahead of the problem, Wyoming has allocated $2.7 million for suppression efforts, including aerial spraying of the pesticide Dimilin, which is fatal to maturing grasshoppers. But Wyoming's congressional delegation—concerned that's not enough—demanded federal help.

"It does not appear as though the USDA has any sense of urgency in the face of this pending plague," the delegation wrote in a letter to Agriculture Secretary Tom Vilsack last month.

Wyoming Gov. Dave Freudenthal this month weighed in as well, writing a public letter urging county, state and federal officials to join forces to prevent "economic and ecological damage." The forecast, he said, suggests an infestation "with disastrous implications."

Mr. Brown, of the USDA, said the department is aware of the severity of the problem but used up nearly all its $5.6 million grasshopper budget last fall counting the insect population—an annual task—and has no money to spray swaths of federally-owned range and grassland. He said the department is looking at ways to boost funding.

If the infestation reaches the level of the 1985 outbreak, he said, federal suppression efforts could cost $40 million.

They're also hoping for help from Mother Nature. A cold, damp spell in late May or June could wipe out a good number of the baby grasshoppers, known as nymphs. But if the weather is warm and dry, "I don't think we'll grow a crop in this part of the country," said Pete Lumsden, a farmer in Loring, Mont.

Grasshopper infestations tend to be cyclical; the numbers mount rapidly for two or three years and then plunge back to normal when the insects run out of food or a disease spreads through overcrowded swarms. Last year was fairly bad in several Western states, so this summer could well be the crest, after which the numbers will fall, entomologists said.
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▼アリゾナにも広がるのだろうか。

「Anthill」（E.O. Wilson教授）

▼ウイキペディア：http://ja.wikipedia.org/wiki/エドワード・オズボーン・ウィルソン▼ハーバード大学比較動物学博物館は一般公開しているのかしら。

WSJ（張付け開始）

BOOKSMARCH 26, 2010

'The Iliad'—With Ants?

A world-renowned biologist tackles fiction in his latest book; of insects and men

By ALEXANDRA ALTER

Humans may think we run the show, but ants dominate the planet. Ants outnumber people by roughly a million to one, and collectively weigh about as much as humanity. Without their soil-tilling skills, entire ecosystems would collapse.

They also make surprisingly compelling fictional protagonists.

Renowned biologist and naturalist E.O. Wilson, who has studied ants for more than 60 years and has won two Pulitzer Prizes, is publishing his first novel, "Anthill," an epic tale of men and insects that centers on the fate of an ant colony in rural Alabama.

Mr. Wilson, 80 years old, says he aimed to draw "a parallel between the epics of the ants and the epics of competing human societies."

The parallels are plentiful: in "Anthill," Mr. Wilson describes how ants build elaborate cities, grow and store food to prevent famine, form social hierarchies with worker and soldier castes, keep their young in nurseries and deposit their dead in cemeteries.

Literary bloggers and reviewers have likened Mr. Wilson's narrative treatment of warring ant colonies to the "Iliad." Mr. Wilson describes a miniature version of the Trojan War as battles between rival tribes of ants escalate, an ant city gets invaded and plundered and a once-thriving ant civilization collapses.

Mr. Wilson, who's published more than 20 nonfiction books, says he turned to fiction because he figured a novel about environmental conservation could reach more readers than a science book. "People respect nonfiction, but they read novels," he says.

Mr. Wilson's prose in "Anthill" at times resembles his detailed descriptions of nature in his memoir, "Naturalist." He cites Sinclair Lewis's novel, "Arrowsmith," about a doctor, and other books about scientists as influences.

"Anthill" also allowed Mr. Wilson to revisit his Alabama childhood. Its central human character, Raff Cody, is an Alabama native who's drawn to nature and fascinated by ants. Rather than becoming a biologist, Raff goes to law school. He eventually tries to stop real estate developers with plans to build homes on pristine land where Raff studied ant colonies as a college student.

"The Anthill Chronicles," a 72-page novella at the center of the 378-page novel, is a retelling of Raff's college anthill thesis, which details the rise and collapse of rival ant colonies. In it, Mr. Wilson describes how the death of one colony's queen leads to its invasion by a rival colony, and how a genetic mutation in another group of ants gave rise to a super colony (normally, only the queen is permitted to lay eggs, but a mutation suppresses the ants' ability to distinguish their queen's smell, so other ants begin breeding).

Mr. Wilson says all the natural descriptions in the book are fact-based. When pressed, he offers a qualification: the ants are a "compound" character based on four different species—fire ants, harvesting ants, honey-pot ants and spiny tree ants.

"I wanted these ants, in one species, to tell some of the most interesting stories that you can find in ants collectively," he said.

The martial tournaments he describes, where soldier ants from rival colonies parade in front of one another and push each other to assess each other's strengths, are based on honey-pot ant behavior, he says. The soldier ants, with their heavy armament, resemble spiny ants. The ants' ultra-aggressive behavior is modeled on fire ants, he says.

Mr. Wilson says the novel's descriptions of ants' emotions is "the one real stretch," although he adds that ants respond to threats and other stimuli in ways that resemble humans. "Ants show behavior which is closely similar to human behavior expressing emotions of fear, anger and panic," he says.

"Anthill" marks another milestone in Mr. Wilson's long and sometimes turbulent career. A professor of entomology at Harvard University, Mr. Wilson has written books on evolution, genetics, conservation and religion. In the 1950s and 1960s, he led pioneering research on ant communication. One of his key discoveries involved teaming up with chemists to detect miniscule traces of the pheromones, or chemical markers, that ants use to send messages.

In the 1970s, Mr. Wilson ventured into the often controversial field of sociobiology, and was widely criticized for arguing that genes drive human behavior. Some critics compared his ideas to Nazi ideology; one group of protesters poured water on him at a public lecture. But a he later won a Pulitzer Prize for his book "On Human Nature," which explains how various human behaviors arose through gene selection and evolution. He won a second Pulitzer for his 1990 book, "The Ants," co-written with Bert Hölldobler.

Mr. Wilson says it was refreshing to write fiction late in life, after so many years of writing scientific exposition. Then he tries to downplay the remark.

"Maybe you shouldn't mention that I'm 80 years old," he says. "I wouldn't want to read a novel by an 80-year-old."

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フンコロガシ

3月10日。雑誌Economistに興味深い記事を発見。


表題：Horny ladies
副題：If females must compete, evolution will furnish them with weapons to do so
日付：Mar 4th 2010
本文：
（張付け開始）
WHEN a species evolves traits that seem to have little to do with individual survival—bright colours, say, or oversize horns, it is typically the male alone who sports these excesses. Observing this, Charles Darwin proposed the idea of “selection in relation to sex” as a follow-up to his theory of natural selection. He defined it as the struggle between members of one sex, “generally male”, to possess the other. The plumage of peacocks attracts peahens. The stag’s antlers are there to fight off other stags. And so on.
But females, it turns out, have some tricks of their own. Nicola Watson and Leigh Simmons of the University of Western Australia have published a paper this week in the Proceedings of the Royal Society about Onthophagus sagittarius, a species of dung beetle in which not only do both sexes sport horns, but those of the females are larger than those of the males. They set out to discover whether female competition accounted for these impressive armaments, and whether there was a trade-off between horns and fecundity.
There are around 2,000 species of dung beetle. All, though, live their lives around faeces. In the case of O. sagittarius, each female constructs a tunnel after she has mated and then packs it with the stuff in the form of a brooding ball, on which she lays her eggs. Her mate guards the entrance, fighting other males to stop them entering the tunnel and cuckolding him. Tunnels are often so close together, however, that other females may break in to their neighbours’ underground, to try to steal dung. Females, therefore, are constantly in conflict with other females, which is why they need horns.
In their laboratory in Perth, Ms Watson and Dr Simmons divided their female beetles into three groups, according to body size. Some of each group were allowed to mate with fertile male beetles. The others mated with beetles rendered sterile by irradiation. This ensured that all female beetles would become pregnant, but those who mated with irradiated males were impregnated by damaged sperm, and would not lay viable eggs. The researchers could thus put three females into a burrow and allow them to compete yet, by ensuring that only one of those females had mated with a fertile male, they could be sure that all the grubs in a burrow were hers.
By comparing all possible combinations of females in this way (mating two of the three sizes with sterile males), and also looking at the success of females who were able to lay their eggs without competition, Ms Watson and Dr Simmons showed that the bigger a female is, the more reproductively successful she is. No surprises there.
The next stage, though, was to do the same experiment, but match females who were the same size except for their horns, in order to see if a bigger horn results in more offspring. The reason to ponder that it might not—and the presumed reason why females of most species do not go in for sexually selected accoutrements—is that such things are costly to grow and maintain. The resources a female spends doing so are therefore unavailable for turning into eggs.
In fact, Ms Watson and Dr Simmons found, horn size was even more important than body size for determining reproductive success. Fending off females who have designs on your dung-ball is evidently more important than laying extra eggs.
If the evolutionary circumstances demand it, then, females can be just as aggressive as males. But they are being aggressive to a different end. This is no struggle to possess the opposite sex, so does it qualify as sexual selection?
That is a matter of definition, but it does go to the heart of the difference between the sexes. Males compete because the more females they inseminate, the more genes they will leave behind. Females mainly let the males get on with this, and pick the winners. They increase their genetic contribution not by promiscuity but by nurturing. If that requires violence, so be it. As to whether there are any human parallels, Ms Watson herself would not be drawn. She did, however, observe that “somebody suggested stilettos.”
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