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Female Fish Choose Attractive Friends to Avoid Attention

By Guest PostDecember 8, 2011Naturearipo river, attractive friends, females, freshwater fish, male attention, mating, receptive, reduce harassment, safi darden, scientists, sexual attention, sexual pheromone, species, trinidad, trinidadian guppy, universities of exeter

Scientists have observed a strategy for females to avoid unwanted male attention: choosing more attractive friends.

Published in the journal Proceedings of the Royal Society B, the study is the first to show females spending time with those more sexually attractive than themselves to reduce harassment from males.

Carried out by the Universities of Exeter and Copenhagen, the study focuses on the Trinidadian guppy, a species of small freshwater fish. It shows that the females choose companions that are relatively more attractive than themselves and in this way reduce harassment from males. The research shows that the tactic is successful and by ensuring they are less attractive than other group members, the fish experience less harassment and fewer mating attempts from males. (more…)

Powerful Mathematical Model Greatly Improves Predictions for Species Facing Climate Change

By Guest PostDecember 4, 2011Environment, Nature, Scienceatmosphere and oceans, beetle, bridgett vonholdt, carbon dioxide emissions, coat color gene, coat color phenotype, daniel macnulty, daniel stahler, earth temperature, ecological impacts, ecological model, ecological parameters, ecosystem, Environment, environmental change, general model, genetics, global warming, gray wolf, grizzly bears, harmony, health of populations, heterozygotes, high arctic, integral projection model, ipm, mathematical model, new model, plants, polar bear, population ecology, population genetics, predictive model, quantitative genetics, robert wayne, species, sub fields of ecology, tim coulson, trophic cascade, wolf, wolf population, wolves, yellowstone, yellowstone national park

UCLA life scientists and colleagues have produced the most comprehensive mathematical model ever devised to track the health of populations exposed to environmental change.

The research, federally funded by the National Science Foundation, is published Dec. 2 in the journal Science.

The team’s groundbreaking integral projection model, or IPM, unites various sub-disciplines of population biology, including population ecology, quantitative genetics, population genetics, and life-span and offspring information, allowing researchers to link many different data sources simultaneously. Scientists can now change just a single variable, like temperature, and see how that affects many factors for a population. (more…)

Frogs’ Amazing Leaps Due to Springy Tendons

By Guest PostDecember 3, 2011Nature, Science3 d x ray video technology, biomechanics of frog jumping, brown university, bush babies, calaveras county, elastic mechanism, elastic structure, frog jumping, frog jumping competition, frogs, grasshopper, guinea fowl, henry astley, humble flea, invertebrates, milliseconds, muscles, northeast united states, northern leopard frog, pond frog, rana pipiens, richard lewis, species of frogs, thomas roberts, vertebrates

*The secret to frogs’ superlative jumping lies in their tendons. Researchers at Brown University, filming frogs jumping at 500 frames per second with special X-ray technology, show that the frog’s tendon stretches as it readies its leap and then recoils, much like a spring, when the frog jumps. The finding could explain how other animals are exceptional leapers. Results appear in Biology Letters.*

PROVIDENCE, R.I. [Brown University] — Some species of frogs and many other animals are able to jump far beyond what appear to be their capabilities. The trained contestants in the frog-jumping competition in Calaveras County, Calif., come to mind, but even ordinary frogs can leap several times farther than their physiology would seem to allow.

“Muscles alone couldn’t produce jumps that good,” said Henry Astley, who studies the biomechanics of frog jumping at Brown University. (more…)

Laborers of Love

By Guest PostNovember 26, 2011General, Natureancient corinth, ancient human skeleton, apostle paul, archaeologist, archaeology lab, artemis, bank of the mississippi, birds of prey, bob kriel, bremer village, bubo, county roscommon, czech republic, deane morrison, excavations, gillian monnier, Greece, horned owl, ireland, john soderberg, keith manthie, minnesota, neanderthal site, peregrine falcon, raptor center, roman cemetery, sue mccarthy, university of minnesota, young owls

*Three volunteers who make a difference*

A murmur runs through the audience as Bob Kriel withdraws his gloved hand from a darkened cage in the front of a small lecture room.

On the glove sits Bubo, a great horned owl. With his piercing eyes and imperial demeanor, this large bird with mottled gray feathers instantly dominates the room.

Kriel, a retired physician who still does clinical research at the University of Minnesota, volunteers weekly at the U’s Raptor Center, where sick and injured birds of prey receive treatment. (more…)

Predators Drive the Evolution of Poison Dart Frogs’ Skin Patterns

By Guest PostNovember 25, 2011Natureamazon forest, athieu chouteau, biologist, butterfly, evolutionary process, exotic defensive signal, forest, heliconius genus, mathieu robert sauve, museum national d histoire naturelle, natural selection, Paris, peruvian, plasticine models, poison dart frog, poisonous frog, predators, ranitomeya, salamanders, skins patterns, snakes, tarapoto, university of montreal

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…)

Gamburtsev Mountains Enigma Unraveled in Interior East Antarctica

By Guest PostNovember 17, 2011Nature, Scienceantarctic rift system, east antarctic, east antarctic rift, gamburtsev high elevation, gamburtsev subglacial mountains, gamburtsevs, ice penetrating radars, ice sheet

The birth of the Gamburtsev Subglacial Mountains buried beneath the vast East Antarctic Ice Sheet – a puzzle mystifying scientists since their first discovery in 1958 – is finally solved. The remarkably long geological history explains the formation of the mountain range in the least explored frontier on Earth and where the Antarctic Ice Sheet first formed. The findings are published this week in the journal Nature. (more…)

MU, Westminster Researchers Find Reduced Bone Density, Stunted Growth in Turtles Exposed to Common Chemical

By Guest PostNovember 16, 2011Environment, Naturebone density, exposure to chemicals, indicator species, pcb exposed turtles, pcb exposure, pentachlorobiphenyls, regulation of hormones, turtles

COLUMBIA, Mo. – Manufactured until 1977, and banned by the Environmental Protection Agency in 1979, pentachlorobiphenyls (PCBs) are chemicals still commonly found in the environment because they break down slowly. (more…)

Yale Research Reveals Ancient Moth’s True Colors

By Guest PostNovember 15, 2011Nature, Scienceanatomical details, birds, camouflage, chemical pigments, colors of ancient beetles, derek e g briggs, electron microscopy, feathered dinosaur, fishes, fossils from germany, Frankfurt, function and evolution, heeso noh, hui cao, insects, long extinct creatures, maria e mcnamara, messel oil shale pit, national science foundation, organisms, original colors of an ancient moth, peabody museum of natural history, structural colors, university college dublin, yale paleontologist, yale university

A research team led by Yale University scientists has for the first time determined the original colors of an ancient moth, based on nearly 50 million-year-old fossils from Germany.

The discovery could help scientists learn the colors of a wide variety of long-extinct creatures, including birds, fishes, and other insects, and shed light on color’s function and evolution. (more…)

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