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The Winners of Mass Extinction: With Predators Gone, Prey Thrives

By Guest PostMay 11, 2011Scienceage of fishes, age of the crinoids, crinoid fossils, devonian era, devonian period, ecology, ecosystem, Environment, fish, fossil record, fossils, hangenberg event, lauren sallan, lotka volterra cycles, marine vertebrate, mass extinction, modern biodiversity, natural experiment, ocean life, ohio state university, paleontologist, population of prey species, predator prey dynamics, predator prey relationships, residual defenses, robert nicholls, thomas kammer, university of chicago, william ausich

*Extinction of fishes 360 million years ago created natural ecology experiment*

In present-day ecology, the removal or addition of a predator in an ecosystem can produce dramatic changes in the population of prey species. For the first time, scientists have observed the same dynamics in the fossil record, thanks to a mass extinction that decimated ocean life 360 million years ago.

What was bad for fish was good for the fish’s food, according to a paper published online in Proceedings of the National Academy of Sciences. Researchers from the University of Chicago, West Virginia University and The Ohio State University found that the mass extinction known as the Hangenberg event produced a “natural experiment” in the fossil record, with results that mirror modern observations about predator-prey relationships. (more…)

How to Tell When Someone’s Lying

By Guest PostMay 11, 2011Culture, Scienceairport, chris green, cognitive interview, detect deception, dishonest people, hong kong, ida rystad, independent commission against corruption, iraq war, los angeles, marine intelligence officers, marines, osama bin laden, psychology, public space, r edward geiselman, red flags, ronald fisher, sandra elmgren, single sentence, subway station, ucla students

*UCLA psychologist helps law enforcement agencies tell truth from deception

When someone is acting suspiciously at an airport, subway station or other public space, how can law enforcement officers determine whether he’s up to no good?

The ability to effectively detect deception is crucial to public safety, particularly in the wake of renewed threats against the U.S. following the killing of Osama bin Laden. (more…)

UF Study Finds Cats No. 1 Predator to Urban Mockingbird Nests

By Guest PostMay 9, 2011Nature, ScienceAmerican crow and swallow-tailed kite, blue jay, cat predation, christine_stracey, dominant nest predator, dominant predator, environmental indicators for metropolitan areas, florida museum of natural history of file photo, may 2011 issue of biological conservation, mockingbird eggs and nestlings, mockingbird nest predators, nesting mockingbirds, opossum, raccoon, scott robinson, squirrel, sylvester & tweety, university of florida

GAINESVILLE, Fla. — A new University of Florida study shows cats are the dominant predator to mockingbird eggs and nestlings in urban areas, prompting conservationists to urge pet owners to keep felines indoors at night.

The findings challenge assumptions that urban areas are places of refuge for nesting mockingbirds, a species researchers say plays an important role in controlling insect pests and serving as environmental indicators for metropolitan areas. (more…)

For UCLA Expert on Chumash Indians, Roughly Hewn Beads are Child’s Play

By Guest PostMay 8, 2011Culture, Scienceanomalous artifacts, artifacts, bead makers, beads, chumash apprentices, chumash indians, shell beads

As the world’s leading authority on beads manufactured from shells by California’s Chumash Indians, UCLA archaeologist Jeanne Arnold was stumped by a series of anomalous artifacts excavated at former settlements on the Channel Islands. (more…)

Four Planets Huddle Up Before Dawn Next Week

By Guest PostMay 8, 2011Scienceanimation, beautiful astronomical photos, binoculars, ecliptic, jupiter, mars, mcdonald observatory, mercury, moon, page sky almanac, planets, sky, skymaps, skywatching events, stardate magazin, venus

AUSTIN, Texas — Four of the five planets visible to the unaided eye huddle quite close together in the pre-dawn sky next week, according to the editors of StarDate magazine.

On the morning of May 10, Venus and Jupiter will stand side by side, quite low in the east, as dawn brightens. If you have a horizon clear of buildings and trees, they will be easy to spot. They are the brightest objects in the night sky after the moon. Venus is the brighter of the two. Jupiter is to its left. (more…)

Measuring the Distant Universe in 3-D

By Guest PostMay 7, 2011Science3 d map, absorption, anže slosar, apache point observatory, bao, baryon acoustic oscillation, baryon oscillation, baryon oscillation spectroscopic survey, berkeley lab, bill carithers, BOSS, centers of galaxies, dark energy, david schlegel, james rich, lyman alpha forest, map intergalactic hydrogen gas, new mexico, of light years, precision tool, quasars, red galaxies, redshift, sdss, sloan digital sky survey, sloan telescope, spectrum, supermassive black holes, universe, wiggly structure

*Berkeley Lab-led BOSS proves it can do the job with quasars*

The biggest 3-D map of the distant universe ever made, using light from 14,000 quasars — supermassive black holes at the centers of galaxies many billions of light years away — has been constructed by scientists with the third Sloan Digital Sky Survey (SDSS-III).

The map is the first major result from the Baryon Oscillation Spectroscopic Survey (BOSS), SDSS-III’s largest survey, whose principal investigator is David Schlegel of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The huge new map was presented at the April meeting of the American Physical Society in Anaheim, CA, by Anže Slosar of Brookhaven National Laboratory. (more…)

Dawn Reaches Milestone Approaching Asteroid Vesta

By Guest PostMay 5, 2011Scienceasteroid, asteroid belt, asteroid vesta, cape canaveral air force station, celestial body, christopher russell, cosmic rays, dawn spacecraft, earth, earth orbiting telescopes, florida, gamma ray, interplanetary travel, marc rayman, NASA, neutron detector, orbit, planet, protoplanet, radio signal, spacecraft, terra incognita, vesta

PASADENA, Calif. — NASA’s Dawn spacecraft has reached its official approach phase to the asteroid Vesta and will begin using cameras for the first time to aid navigation for an expected July 16 orbital encounter. The large asteroid is known as a protoplanet — a celestial body that almost formed into a planet.

At the start of this three-month final approach to this massive body in the asteroid belt, Dawn is 1.21 million kilometers (752,000 miles) from Vesta, or about three times the distance between Earth and the moon. During the approach phase, the spacecraft’s main activity will be thrusting with a special, hyper-efficient ion engine that uses electricity to ionize and accelerate xenon. The 12-inch-wide ion thrusters provide less thrust than conventional engines, but will provide propulsion for years during the mission and provide far greater capability to change velocity. (more…)

Most Powerful Millimeter-Scale Energy Harvester Generates Electricity from Vibrations

By Guest PostMay 4, 2011Scienceconvert, energy harvester cyclic motions, harness energy, high-quality energy-harvesting piezoelectric material, intellectual property, novel silicon micromachining technique, ongoing life-cycle expenses of operating a wireless sensor, pervasive information-gathering sensor networks, sensors, solid-state, ultracapacitor, vibrations

ANN ARBOR, Mich.—Electrical engineers at the University of Michigan have built a device that can harness energy from vibrations and convert it to electricity with five to 10 times greater efficiency and power than other devices in its class. And it’s smaller than a penny.

“In a tiny amount of space, we’ve been able to make a device that generates more power for a given input than anything else out there on the market,” said Khalil Najafi, one of the system’s developers and chair of Electrical and Computer Engineering. (more…)

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