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January 22, 2007
Volume 85, Number 04
p. 72

Psychic Squirrels

Are RED SQUIRRELS psychic? Scientists aren't willing to go that far, but they do say the animal has a built-in ability to stay one step ahead of its food source. According to an article published in Science, trees use an evolutionary "swamp and starve" tactic in attempts to prevent animals from eating its seed (Science 2006, 314, 1928). The trees attempt to starve predators some years, so that in fruitful years, there will be fewer seed predators around to consume the bountiful crop.

There's just one hitch in the near-perfect plan: The American and Eurasian red squirrel has concocted a counterattack. The red squirrel has somehow discovered how to anticipate a boom seed season and has responded by defying nature and producing an unusual second litter of pups.

"American reds gave birth to larger litters in advance of high food production and were most likely to breed as yearlings," the researchers state. "The most striking effect was that females produced a second litter after a successful first litter in advance of high food production. In most cases, females were still lactating with the first litter when they conceived the second, suggesting that the normal physiological inhibition of ovulation by lactation characteristic of mammals had been circumvented."

Although scientists have yet to understand how the red squirrel is able to predict the trees' behavior, they suspect it is linked to "visual or chemical stimuli," such as buds, flowers, or pollen cones, which "may be correlated with the size of the forthcoming seed crop." Now that's nuts.

Viagra: The Anticancer Drug

In case anyone needs a fresh reason to love Viagra, scientists at Johns Hopkins Kimmel Cancer Center have discovered that the IMPOTENCE DRUG turns on the body's awareness to colon and breast cancers.

Dušan Zidar/Fotolia

The Journal of Experimental Medicine reports that a team of scientists at Hopkins has been investigating ways to prevent tumors from recruiting myeloid-derived suppressor cells and regulatory T cells, which suppress the body's awareness of the tumors (J. Exp. Med. 2006, 203, 2566).

Suppression of the T cells involves nitric oxide, which is affected by Viagra and other impotence drugs.

So the researchers hypothesized that Viagra might provide a boost to the immune system. Indeed, tests on mice showed the drug increased the number of cytotoxic T cells and reduced tumor outgrowth by 50-70%.

Although Viagra did not eliminate the tumors, it did significantly slow their progression.

Tests on human cancer cells had similar results, and clinical trials are currently being planned.

Super Spuds

According to USA Today, biologists at Idaho-based J. R. Simplot are working to create the first GENETICALLY MODIFIED POTATO. The potato—a modified Russet Ranger—could contain healthier starch, have a stronger taste, and be resistant to bruises and sprouts.

Its gene structure would also reject acrylamide, a chemical agent once used to treat sewage that has been linked to various types of cancer in laboratory mice. Company officials state that the super spud will not be ready to market for another five to 10 years.

This week's column was written by Faith Hayden. Please send comments and suggestions to