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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…)

Predators Drive the Evolution of Poison Dart Frogs’ Skin Patterns

By Guest PostNovember 25, 2011Naturedart frog, evolution, poison dart frogs, poisonous frog, skin patterns

Natural selection has played a role in the development of the many skins patterns of the tiny Ranitomeya imitator poison dart frog, according to a study that will be published in an upcoming edition of American Naturalist by University of Montreal biologist Mathieu Chouteau. The researcher’s methodology was rather unusual: on three occasions over three days, at two different sites, Chouteau investigated the number of attacks that had been made on fake frogs, by counting how many times that had been pecked. Those that were attacked the least looked like local frogs, while those that came from another area had obviously been targeted. (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…)

Canadians More Likely to Support Policies to Address Climate Change Than Americans

By Guest PostFebruary 28, 2011Environmentamerican public opinion, climate change, evolution, global warming

ANN ARBOR, Mich.— Americans are less willing to open their wallets to pay for increased production of renewable energy resources than Canadians, a new University of Michigan report indicates. (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…)

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…)

Mammals Grew 1,000 Times Larger After the Demise of the Dinosaurs

By Guest PostNovember 27, 2010Sciencebody size, evolution, existence of dinosaurs, extinction of dinosaurs, land mammals

NSF enabled the assembly of an international, interdisciplinary team that was the first to quantitatively document body size patterns over the past 100 million years

Researchers have demonstrated that the extinction of dinosaurs some 65 million years ago paved the way for mammals to get bigger, about a thousand times larger than they had been when dinosaurs roamed the earth. The study, released in the journal Science, is the first to quantitatively document the patterns of body size of mammals after the existence of dinosaurs. (more…)

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