By JIM ROBBINSPublished: April 27, 2010
HELENA, Mont.— Once feared extinct, the giant Palouse earthworm, reputed to grow up to three feet long and smell like lilies, has been found alive.
It turns out though, experts say, the worm is not a giant, nor does it have a lilylike scent.
Researchers thought the worm, translucent with the pink head and last seen in the 1980s, might be extinct because its habitat, the Palouse prairie region of Idaho and Washington, is almost gone. On March 27, however, Karl Umiker, a University of Idaho research support scientist, working with Shan Xu, a graduate student from Chengdu, China, discovered two giant Palouse earthworms, a juvenile and an adult, on a small patch of native prairie near Moscow, Idaho.
As it turns out, the worms are bigger than night crawlers but not giant. The two specimens, the adult of which had to be killed and dissected to determine whether it was indeed a giant Palouse earthworm, were about seven inches long when they came from the ground.
“But when we stretched it out and relaxed it, the adult earthworm got bigger,” said Jodi Johnson-Maynard an associate professor of soil and water management and Mr. Umiker’s supervisor. “It’s between 9 and 10 inches.”
That is a far cry from earlier claims of three-foot worms. “We tried to track that story down,” Dr. Johnson-Maynard said, and discovered that many years ago there was one giant specimen. “Apparently some boy was swinging it in the air like a rope, and it stretched.”
Giant earthworms do exist in Africa and Australia, she said, and so it was thought that a North American version was possible.
And the fragrance of lilies? “That I have never noted,” Dr. Johnson-Maynard said. She did not know the origin of that claim.
Still, Dr. Johnson-Maynard said that finding the worms was a scientific coup. “Most people thought it was extinct, or that it never even existed,” she said, “like the Loch Ness monster.”
The worms are transparent, and their organs and food can be discerned through their skin. The species was first described in 1897.
The last live worms were found in the 1980s. Worms were found by researchers in 2005 and 2007, but they were killed during recovery. There were numerous sightings in the 19th century before most of the native prairie was plowed up for wheat. Environmentalists have petitioned the federal government to list the worm as endangered.
Dr. Johnson-Maynard was disappointed that the adult had to be killed to be identified, but inspecting digestive organs is the only way to tell for sure. Now, however, she said, DNA from the sacrificial worm should enable less drastic measures.
Dr. Johnson-Maynard suspects that there are more giant Palouse earthworms, and that they are considered rare in part because they are so hard to find. While most worms live in the top foot of soil, she said, “the giant Palouse can burrow much deeper, about 15 feet.” They can also sense disturbance and flee to deeper ground when researchers are digging.
The researchers used an electroshock device to find the worms. The location technique, called the octet method, involves sticking eight electrodes into the ground in a one-foot-circle and sending electricity through them. It is believed to be what brought the worms to the surface.
The scientific name for the worm is Driloleirus americanus, a separate genus and species than other worms. The creature is different from other worms in a couple of ways. It has more nephidia, a kidney-like organ that allows it to live in dryer conditions than other worms. And their clitellum, a smooth band that all worms have, is in a different location.
The captured juvenile is resting comfortably, Dr. Johnson-Maynard said, adding, “We have it in a cooler in soil with ice packs.”
http://www.nytimes.com/2010/04/28/science/earth/28earthworm.html?ref=us
(Submitted by Brian Chapman)
See also: http://www.idahostatesman.com/2010/04/27/1169673/apnewsbreak-idaho-scientists-find.html#ixzz0mUBrfYXv
And: http://news.ca.msn.com/world/cbc-article.aspx?cp-documentid=24061208
(Submitted by G. A. Christian Bilou)
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