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50-Million-Year-Old Cricket and Katydid Fossils From Colorado Hint at Origin of Insect Hearing

By Guest PostJanuary 7, 2012Nature, Science50 million year old, abdomens, chorus of crickets, colorado, crickets and katydids, crucial survival advantage, dena smith, eardrum, evidence of ears, evolution, fossil evidence, fossil insect, front legs, grasshoppers, green river formation, green river fossils, lacewings, lake deposits, modern insects, museum, paleontologist, roy plotnick, tachinid fly, utah, wyoming

*The team scoured more than 500 museum drawers of Green River fossils for crickets and katydids with intact front legs, looking for evidence of ears.*

How did insects get their hearing? A new study of 50-million-year-old cricket and katydid fossils sporting some of the best preserved fossil insect ears described to date are helping to trace the evolution of the insect ear.

According to paleontologist Dena Smith of the University of Colorado Boulder’s Museum of Natural History and University of Illinois Professor Roy Plotnick, who collaborated on the new study at the National Evolutionary Synthesis Center, or NESCent, in Durham, N.C., insects hear with help from some very unusual ears. (more…)

Close Family Ties Keep Microbial Cheaters in Check, Study Finds

By Guest PostDecember 16, 2011Scienceamoebae, Antarctica, canopies, clonal lineage, cosmopolitan groups, david queller, deserts, dicty, dictyostelium discoideum, e coli, evolution, forest park, genes, jennie kuzdzal fick, joan strassmann, kissing kin, life cycles, multicellular organisms, mutation, national science foundation, obligate cheaters, sam scheiner, sara fox, single cell, slime mold, social amoeba, st. louis, tropical forests, washington university

*Experiments on “slime mold” explain why almost all multicellular organisms begin life as a single cell*

Any multicellular animal, from a blue whale to a human being, poses a special challenge for evolution.

Most of the cells in its body will die without reproducing; only a privileged few will pass their genes to the next generation.

How could the extreme degree of cooperation required by multicellular existence actually evolve? Why aren’t all creatures unicellular individualists determined to pass on their own genes? (more…)

Human Prejudice Has Ancient Evolutionary Roots

By Guest PostMarch 19, 2011Sciencecoast of puerto rico, common ancestor, evolution, evolutionary theorists, human, human culture, human nature, iat, implicit attitudes, ingenious experiments, island, laurie santos, mahzarin banaji, margaret martinez, monkeys, natashya gutierrez, neha mahajan, primate, psychologist, sequence of photos, us versus them

The tendency to perceive others as “us versus them” isn’t exclusively human but appears to be shared by our primate cousins, a new study led by Yale researchers has found.

In a series of ingenious experiments, Yale researchers led by psychologist Laurie Santos showed that monkeys treat individuals from outside their groups with the same suspicion and dislike as their human cousins tend to treat outsiders, suggesting that the roots of human intergroup conflict may be evolutionarily quite ancient. (more…)

How Nature’s Patterns Form

By Guest PostFebruary 23, 2011Nature, Sciencealan newell, applied stress, bracts, d'arcy wentworth thompson, evolution, fingerprints, florets, flower arrangements, flowers, good poem, how plants grow, leopards, mari n jensen, mathematical biologist, mathematical models, mathematics, on growth and form, patterns, sand ripples, stickers, the universal nature of fibonacci patterns, universal features

*Alan Newell, a UA mathematics professor, studies patterns in nature, which he said have features that are universal*

When people on airplanes ask Alan Newell what he works on, he tells them “flower arrangements.”

He could also say “fingerprints” or “sand ripples” or “how plants grow.” (more…)

Astronomers Identify Thick Disc of Older Stars in Nearby Andromeda Galaxy

By Guest PostFebruary 16, 2011Scienceandromeda, andromeda galaxy, astronomer, evolution, formation of the andromeda system, galactic evolution, hawaii, hubble imaging, keck observatory, keck telescope, m31, michael rich, michelle collins, Milky Way, motions, robert gendler, scott chapman, spiral galaxy, spiral structure, thick stellar disc

An international team of astronomers has identified for the first time a thick stellar disc in the Andromeda galaxy, the nearest large spiral galaxy to our own Milky Way.

The discovery of the thick disc, a major result from a five-year investigation, will help astronomers better understand the processes involved in the formation and evolution of large spiral galaxies like ours, according to the team, which includes UCLA research astronomer Michael Rich and colleagues from Europe and Australia. (more…)

Colossal Fossil: Museum’s New Whale Skeleton Represents Decades of Research

By Guest PostDecember 18, 2010Nature, Scienceamy harris, anthropology, basilosaurus isis, basilosaurus skeleton, egyptian desert, evolution, extinct whale, fossil, fossil whales, fossilized basilosaurus vertebra, museum, natural history, philip gingerich, sea, sediment, skeleton, the evolution of whales, unesco world heritage site, valley of the whales, wadi hitan, william sanders

ANN ARBOR, Mich.—There’s a whale of a new display at the University of Michigan Exhibit Museum of Natural History, a leviathan that represents a scientific saga of equally grand proportions.

A complete, 50-foot-long skeleton of the extinct whale Basilosaurus isis, which lived 37 million years ago, now is suspended from the ceiling of the museum’s second floor gallery and will reign over an updated whale evolution exhibit scheduled to open in April 2011. (more…)

Discovery Triples Number of Stars in the Universe

By Guest PostDecember 2, 2010Scienceastronomers, charlie conroy, dark matter, dim stars, earths, elliptical galaxies, evolution, galaxies, galaxy formation, gliese 581, hawaii, keck observatory, Milky Way, optical telescopes, pieter van dokkum, red dwarfs, sun, theoretical models, twin telescopes

Astronomers detected the faint signature of small, dim red dwarf stars in nearby galaxies (right), and found they are much more numerous than in our own Milky Way (left). Image credit: Patrick Lynch/Yale University

Astronomers have discovered that small, dim stars known as red dwarfs are much more prolific than previously thought — so much so that the total number of stars in the universe is likely three times bigger than previously believed.

Because red dwarfs are relatively small and dim compared to stars like our Sun, astronomers hadn’t been able to detect them in galaxies other than our own Milky Way and its nearest neighbors before now. Therefore, they did not know how much of the total stellar population of the universe is made up of red dwarfs.

Now astronomers have used powerful instruments on the Keck Observatory in Hawaii to detect the faint signature of red dwarfs in eight massive, relatively nearby galaxies called elliptical galaxies, which are located between about 50 million and 300 million light years away. They discovered that the red dwarfs, which are only between 10% and 20% as massive as the Sun, were much more bountiful than expected. (more…)

‘Galapagos’ survived

By ShamsAugust 9, 2010Environment, Naturecharles darwin, endangered places, evolution, galapagos, island, un

The Galapagos Islands are no more ‘in danger’.

(more…)

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