pheromone limits male mouse arousal

Tears of sexually immature female mice inhibit the mating behavior of male mice, a Japanese research team has found.

The research group, which includes Kazushige Tohara, a professor at the University of Tokyo and an expert on applied biological chemistry, released the finding in an electronic version of the British journal Nature in its Thursday edition.

A pheromone called exocrine-gland secreting peptide 22 (ESP22), which is abundant in tears of 2- to 3-week-old female mice, inhibits the sexual arousal of male mice, the team found.

It is known that pheromones increase sexual arousal in animals, but this is the first time a pheromone has been found to decrease sexual excitement in a mammal.

The researchers studied two groups of mice: one that secreted ESP22 and another that lacked the pheromone. Then the researchers studied the sexual responses of the male mice toward the females from the two groups.

The sexual behavior of male mice toward the females that did not secrete ESP22 was three to five times greater than that toward females that produced the pheromone. However, application of ESP22 to the bodies of the females that lacked the pheromone inhibited sexual behavior of the males.

ESP22 is detected by the vomeronasal organ, which is located below the nasal cavity, stimulating an area of brain that controls instinctive behavior. Human beings lack the system that produces and detects the pheromone.

time to rewrite the book on 'asteroid'

It was hardly the greatest mystery in the cosmos, and solving it won't change the course of science. But a Fort Lauderdale, Fla., astronomer has cracked a 200-year-old puzzle: Who coined the word "asteroid"?

Publishers might want to take notice.

"It will actually cause books to be rewritten and dictionaries to be revised," said Clifford Cunningham, whose research revealed the true creator of the word used to describe the rocky space travelers.

It wasn't William Herschel, the famed court astronomer for King George III, who is credited with inventing the term in 1802, Cunningham found. Rather it was the son of a poet friend of Herschel's, Greek scholar Charles Burney Jr., who originated the term asteroid, which means "starlike" in Greek.

"Herschel was certainly one of the greatest astronomers of all time, but this is not a credit we can give him," said Cunningham, who presented his findings last week at the 45th annual convention of the astronomical society's Division of Planetary Sciences.

Erik Gregersen with Encyclopedia Britannica said he will review Cunningham's work and make any necessary changes.

SPONGES RECYCLE FOOD FOR REEFS

It is known as Darwin's paradox: Coral reefs are rife with animal and plant life, yet exist in clear, nutrient-free waters. Where is the food coming from?

The answer is sponges, say researchers from the Netherlands.

Sponges take organic matter that is cast off by coral and algae and recycle it into food that is consumed by larger organisms such as snails and crabs, according to a new study in the journal Science. The result is a "sponge loop" that allows the reefs to thrive in otherwise inhospitable waters.

"The largest source of energy and nutrients produced on the reef consists of things you cannot see," said the lead author, Jasper M. de Goeij, a marine biologist at the University of Amsterdam. "And no one else but sponges can make use of that source."

The findings could aid in efforts to conserve endangered coral reefs, de Goeij said.

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