scientists

Human impact on a food source unexpected

Raleigh, N.C. -- Human impact on a shellfish consumed in the Pacific for thousands of years may have caused the species to actually increase in size, U.S. researchers say.

Scientists at North Carolina State University, in a counterintuitive finding, say the average size of the humped conch, a food source in the Pacific islands for 3,000 years, has increased in spite of -- or even possibly because of -- increased human activity in the area, a university release said Tuesday.

Quest for more computer memory ongoing

New York -- U.S. scientists say new technologies may bypass barriers to the miniaturization of computer memory, vital to the consumer electronics revolution.

The limits of physics had loomed as a possible slowdown in the pace of miniaturization that has allowed the ability to pack ever more power into ever-smaller devices such as laptops, smart phones and digital cameras, The New York Times reported.

Now two emerging technologies could overcome that barrier, researchers say.

At Rice University, scientists say they have succeeded in building reliable small digital switches, essential to computer memory, that could be made at a significantly smaller scale than is possible using conventional methods.

Gentler method of dolphin study described

Baltimore -- U.S. researchers have demonstrated a kinder, gentler way of collecting dolphin DNA for scientific study, scientists say.

A harmless "breath" test using the dolphin's "blow" or exhalation is replacing traditional "dart biopsying," which involves firing a dart with a small barb into the flank of the animal that yields a plug of tissue, BBC News reported Monday.

Dolphins are mammals and must breathe out through blowholes on the tops of their heads. The "blow" is exhaled at great force, and cells from the surface of the lungs from which DNA can be extracted can be found in their blow and easily collected.

Horseshoe crabs suffer with climate change

Washington -- Horseshoe crab population decline is being blamed on climate change and compared to similar declines at the end of the last Ice Age, U.S. scientists say.

The research indicates horseshoe crab numbers may continue to fall because of predicted climate change, a U.S. Geological Survey release said Monday.

The study confirmed recent significant population declines in all areas where horseshoe crabs occur along the Atlantic Coast from Maine to Florida and the eastern Gulf of Mexico.

Ancient 'relic' coral reef studied

Washington -- The remains of an ancient and extensive coral reef in the southern Pacific Ocean, the southernmost of any existing reef, have been discovered, researchers say.

A team of scientists from Australia and New Zealand used sonar and core samples to examine a relic reef found in water about 75 feet deep around Lord Howe Island 370 miles east of the Australian mainland, an article in the U.S. journal Geophysical Research Letters says.

The reef thrived from about 9,000 to 7,000 years ago, researchers say, and covered an area 20 times larger than the island's modern reef, the furthest south in the world.

About 7,000 years ago the reef was drowned, probably due to abrupt sea level rise, and then shrank to its current size.

Calif. hit by 'nuisance' algae in rivers

Sacramento -- Scientists say they don't know why a "yucky" kind of algae is fouling a stretch of a California river to the displeasure of swimmers and fishermen.

About 10 miles of the Bear River northeast of Sacramento is clogged with a strange algae called "didymo," short for its scientific name, Didymosphenia geminata, The Sacramento Bee reported Monday.

People's dislike of the algae has earned it the nickname "rock snot."

"No doubt, it is pretty yucky, and that's the complaint from a lot of recreationists," Leah Elwell at the Center for Aquatic Nuisance Species in Livingston, Mont., said. "If you're kayaking, you don't want to get a mouthful of that. It does kind of foul up your day."

Florida coral reefs damaged by cold water

Palm Beach, Fla. -- A rare series of cold-water upwellings from the deep ocean has severely damaged coral reefs in Florida already stressed by pollution, scientists say.

The blasts of cold water hit the reefs in July, fatally bleaching large areas of coral, already under siege from sewage, fertilizers, pesticides and algae, The Palm Beach (Fla.) Post reported.

Much of the damage hit staghorn coral, an endangered species.

The impact is not just environmental; there an economic cost as well because marinas, boat-sellers, bait shops and fishing and dive charters depend on the health of the reefs.

Oddly shaped Mars crater a cosmic puzzle

Paris -- An elongated crater on Mars is a mystery, say European scientists scrambling for an explanation of its odd shape.

Named Orcus Patera, the enigmatic elliptical depression lies near Mars's equator, in the eastern hemisphere of the planet. Located between the volcanoes Elysium Mons and Olympus Mons, how it was formed remains a mystery, a European Space Agency release said Friday.

The term 'patera' is used for deep, complex or irregularly shaped volcanic craters, but despite its name and its location near known volcanoes, the actual origin of Orcus Patera is still unknown, scientists say.

High-res camera snaps water ice on Mars

Tucson -- A NASA spacecraft with a high-resolution camera has photographed a young Mars crater and found frozen water in it, scientists say.

A recent image from NASA's Mars Reconnaissance Orbiter HiRISE camera shows water ice at the bottom of a 20-foot-wide crater on the planet's surface, SPACE.com reported Friday.

Researchers suspect the crater in the northern hemisphere formed recently, no earlier than April 2004, Nathan Bridges, a HiRISE science team member at the University of Arizona, said.

The crater appeared in photos taken between June 6 and July 7.

"It's showing we're getting ice pretty far south," Bridges said. "As we continue to look at these things it's a good way to determine where shallow ice is on Mars."

Scientists see uses for odd 'dry water'

Boston -- Scientists say a substance dubbed "dry water" resembling powdered sugar could absorb and store carbon dioxide, the major greenhouse gas causing global warming.

In a presentation Wednesday at the annual meeting of the American Chemical Society, scientists hinted at additional uses, including a greener, more efficient method of jump starting the chemical reactions involved in the creation of hundreds of consumer products, and a safer way to store and transport hazardous industrial materials, ScienceDaily.com reported.

"There's nothing else quite like it," researcher Ben Carter said. "Hopefully, we may see 'dry water' making waves in the future."

Study: Old galaxies surprisingly energetic

Los Angeles -- Giant halos of ultraviolet light around ancient galaxies have some U.S. scientists re-thinking the evolution of galaxies in the universe, they say.

The odd ultraviolet formations were spotted around several aged galaxies that astronomers had presumed to be astronomically inactive, SPACE.com reported Wednesday.

"We haven't seen anything quite like these rings before," researcher Michael Rich at the University of California, Los Angeles, said. "These beautiful and very unusual objects might be telling us something very important about the evolution of galaxies."

Astronomers looked at 30 "early" galaxies to try to find out why, though ancient and exhibiting now visible evidence of star formation, were emitting such energetic light.

Study: Star dust could be smashed planets

Cambridge, Mass. -- Large clouds of dust found around binary star systems could the pulverized remains of planets, U.S. scientists say.

Scientists at Harvard University using NASA's Spitzer Space Telescope spotted what they called surprising amounts of dust surrounding three mature, closely-orbiting star pairs, a university release says.

In trying to explain where the dust came from, some astronomer say it could be all that's left of the aftermath of tremendous planetary collisions.