January 13, 2010
By LESLIE KAUFMAN
After more than a decade of resistance, the Fish and Wildlife Service said Tuesday that it would reverse previous decisions and protect the habitat of the jaguar.
The sleek, ferocious cats have been listed since 1997 as endangered, the highest level of peril for a wild species. Still, the government has never designated critical habitat for the jaguar or come up with a formal recovery plan, steps that are commonly taken under the Endangered Species Act.
The federal government has given varying reasons for its refusal to act. In 1997, the Fish and Wildlife Service said that to protect the jaguar’s habitat, it would have to make public maps of its range. That would make the animals vulnerable to more poaching, already a primary cause of deaths, it said.
In 2006, the service argued that jaguars were primarily native to South and Central America and that their range in the United States was largely incidental to its survival.
Wildlife advocates sued to protest those findings, pointing out that jaguars were thought to have once ranged from Louisiana to California, although they had rarely been seen in recent decades.
Last March, the Federal District Court in Tucson told the government that it would have to come back with a decision that was soundly based in science.
In theory, the service could have sought again to rule out habitat conservation. But this time the government said it would move to protect critical habitat and would publish a description of the land proposed for the designation.
It also agreed to develop a formal recovery plan, which will envision how the jaguar might make a recovery.
The Fish and Wildlife Service says there are no known jaguars in the United States today. The last jaguar known to exist within the nation’s borders died last March.
However, there are nearly 5,000 in Mexico, and more ranging as far south as Argentina and Paraguay.
The notion behind a critical habitat designation is to enable the jaguar to survive if it ranges north again.
Protecting the jaguar’s habitat will be a complicated challenge. The cats can range over hundreds of square miles to hunt prey, and ranchers have fiercely opposed protection.
Conservationists were exultant on Tuesday, with some predicting that the protection of such a far-ranging species could have a broader impact.
“It will reorient land conservation in the Southwest,” said Michael J. Robinson, conservation advocate with the Center for Biological Diversity, a Tucson-based group that brought the lawsuit.
When the government weighs a plan to allow tree cutting or mining on public lands, for example, he said, it will have to ensure that it will not harm the jaguar’s critical habitat.
“We will see planning to ensure jaguars can reach each other,” he said.
http://www.nytimes.com/2010/01/13/science/earth/13jaguar.html?ref=science
Wednesday, January 13, 2010
Wednesday, January 6, 2010
White Lizards Evolve in New Mexico Dunes
January 5, 2010
Observatory
By HENRY FOUNTAIN
The White Sands of New Mexico are a good place to study evolution in progress. One reason is that the terrain, gypsum dunes white as a sheet of paper, is so different from the surrounding area. Another is that the dunes formed only about 6,000 years ago.
“From an evolutionary perspective, that’s really the blink of an eye,” said Erica Bree Rosenblum, a professor at the University of Idaho who has been studying evolution at White Sands for much of the past decade. Her focus has been on three lizard species that elsewhere are dark skinned but in White Sands have each evolved a white-skinned variety that makes them hard to find. “It’s really obvious what’s happened,” Dr. Rosenblum said. “Everybody got white so that they could better escape from their predators.” It’s a great example of convergent evolution, of species independently acquiring the same traits.
One question about convergent evolution is the mechanism by which it happens. Sure, these three lizards all developed white skin, but did they do it in the same way? Dr. Rosenblum and her colleagues have provided answers to this question in a paper in The Proceedings of the National Academy of Sciences.
“At first blush it seems like the answer is yes,” she said. In at least two of the lizard species, the researchers found that mutations on the same gene, linked to the production of the skin pigment melanin, were responsible.
The second part of the story is more interesting, Dr. Rosenblum said. In the two species, the mutations are different, and the molecular mechanism by which less melanin is produced is different, too.
And, she said, the different mechanisms have had an effect on how the white-skinned trait has spread through the populations. In one, the mutation has made the white-skinned trait dominant; in the other, the mutation has made it recessive. So, according to basic Mendelian genetics, the trait spreads more quickly in the first lizard species than the second.
Observatory
By HENRY FOUNTAIN
The White Sands of New Mexico are a good place to study evolution in progress. One reason is that the terrain, gypsum dunes white as a sheet of paper, is so different from the surrounding area. Another is that the dunes formed only about 6,000 years ago.
“From an evolutionary perspective, that’s really the blink of an eye,” said Erica Bree Rosenblum, a professor at the University of Idaho who has been studying evolution at White Sands for much of the past decade. Her focus has been on three lizard species that elsewhere are dark skinned but in White Sands have each evolved a white-skinned variety that makes them hard to find. “It’s really obvious what’s happened,” Dr. Rosenblum said. “Everybody got white so that they could better escape from their predators.” It’s a great example of convergent evolution, of species independently acquiring the same traits.
One question about convergent evolution is the mechanism by which it happens. Sure, these three lizards all developed white skin, but did they do it in the same way? Dr. Rosenblum and her colleagues have provided answers to this question in a paper in The Proceedings of the National Academy of Sciences.
“At first blush it seems like the answer is yes,” she said. In at least two of the lizard species, the researchers found that mutations on the same gene, linked to the production of the skin pigment melanin, were responsible.
The second part of the story is more interesting, Dr. Rosenblum said. In the two species, the mutations are different, and the molecular mechanism by which less melanin is produced is different, too.
And, she said, the different mechanisms have had an effect on how the white-skinned trait has spread through the populations. In one, the mutation has made the white-skinned trait dominant; in the other, the mutation has made it recessive. So, according to basic Mendelian genetics, the trait spreads more quickly in the first lizard species than the second.
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