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Migration No Longer Best Strategy for Yellowstone Elk

By Guest PostJune 5, 2013Naturearthur middleton, best strategy, dwindling phenomenon, ecological changes, female migratory elk, matthew kauffman, migration, migratory elk, natural experiment, predator management, rocky mountain elk, U.S. Geological Survey, university of wyoming, wgfd, wildlife, yellowstone, yellowstone elk, yellowstone national park, yellowstone wolf reintroduction

LARAMIE, Wyo. — Migratory elk are coming back from Yellowstone National Park with fewer calves due to drought and increased numbers of big predators – two landscape-level changes that are reducing the benefits of migration with broader implications for conservation of migratory animals, according to a new study published in the journal Ecology.

The new study by the Wyoming Cooperative Fish and Wildlife Research Unit – a joint program involving U.S. Geological Survey, the University of Wyoming, and the Wyoming Game and Fish Department, describes a long-term decline in the number of calves produced annually by the Clarks Fork herd, a population of about 4000 elk whose migrants travel annually between winter ranges near Cody, Wyoming and summer ranges within Yellowstone National Park. Migratory elk experienced a 19 percent depression in rates of pregnancy over the four years of the study and a 70 percent decline in calf production over 21 years of monitoring by the WGFD, while the elk that did not migrate, known as resident elk, in the same herd experienced high pregnancy and calf production and are expanding their numbers and range into private lands outside of the park. (more…)

How the turtle got its shell

By Guest PostMay 31, 2013Nature, Scienceallison y hsiang, armadillos, China, eunotosaurus, eunotosaurus fossils, evolutionary origin, evolutionary pathway, fossil record, fossil reptile, gabe s bever, histological analysis, history of life, how, jacques a gauthier, modern turtle model, modern turtles, molecular divergence, most living turtles, placodonts, secret of shell, shell, smithsonian institution, South Africa, torsten m scheyer, turtle, turtle shell, tyler lyson, universitaet zuerich, various lizards, vertebrae, yale peabody museum, yale university

The turtle has been in no rush to give up the secret of its shell — but after two centuries of close study, scientists are filling in the story of a structure unique in the history of life.

New research led by Tyler Lyson of Yale University and the Smithsonian Institution pushes back the origins of the turtle shell by about 40 million years, linking it to Eunotosaurus, a 260-million-year-old fossil reptile from South Africa. The work strengthens the fossil record and bolsters an existing theory about shell development while providing new details about its precise evolutionary pathway. (more…)

Protecting pandas and the planet

By Guest PostMay 30, 2013Naturefate of pandas, future of pandas, giant panda, mountains of wolong, panda habitat, panda population numbers

In the mountains of the Sichuan Province of southwestern China, the Wolong Panda Nature Reserve is home to both the endangered peaceful mountain dwellers it is mandated to protect and the residents of the valley where the habitat of the giant panda is being restored. It’s also home base for research that holds important insights into the future of pandas and people. (more…)

USGS Study Confirms U.S. Amphibian Populations Declining at Precipitous Rates

By Guest PostMay 26, 2013Natureamphibian populations, declines of amphibians, habitats, threatened species, wildlife refuges

CORVALLIS, Ore. — The first-ever estimate of how fast frogs, toads and salamanders in the United States are disappearing from their habitats reveals they are vanishing at an alarming and rapid rate. (more…)

Small, Speedy Plant-Eater Extends Knowledge of Dinosaur Ecosystems

By Guest PostMay 24, 2013Naturedinosaur ecosystems, meat eating dinosaurs, plant eating dinosaur, small dinosaurs

Bethesda, MD — Dinosaurs are often thought of as large, fierce animals, but new research highlights a previously overlooked diversity of small dinosaurs. In the Journal of Vertebrate Paleontology, a team of paleontologists from the University of Toronto, Royal Ontario Museum, Cleveland Museum of Natural History and University of Calgary have described a new dinosaur, the smallest plant-eating dinosaur species known from Canada. Albertadromeus syntarsus was identified from a partial hind leg, and other skeletal elements, that indicate it was a speedy runner. Approximately 1.6 m (5 ft) long, it weighed about 16 kg (30 lbs), comparable to a large turkey. (more…)

A key to mass extinctions could boost food, biofuel production

By Guest PostMay 21, 2013Naturebiofuel production, concentration, extinction events, food crops, frederick dooley, genetic signaling, great dying, hydrogen sulfide, key, level, mass extinction, parts per million, permian period, peter ward, rate of germination, rotten egg smell, species on earth, suven nair, toxic effects, university of washington, water

Hydrogen sulfide, the pungent stuff often referred to as sewer gas, is a deadly substance implicated in several mass extinctions, including one at the end of the Permian period 251 million years ago that wiped out more than three-quarters of all species on Earth.

But in low doses, hydrogen sulfide could greatly enhance plant growth, leading to a sharp increase in global food supplies and plentiful stock for biofuel production, new University of Washington research shows. (more…)

Invasive Crazy Ants Are Displacing Fire Ants, Researchers Find

By Guest PostMay 18, 2013Nature, Science300 pound gorilla, ant species, argentine ant, arthropod species, austin, brackenridge field laboratory, college, crazy ants, ecologically dominant, ecosystem, ed lebrun, florida, Houston, invasive crazy ants, natural control, natural sciences, new orleans, northern argentina, nylanderia fulva, omnivorous, rasberry crazy ants, southern brazil, southern hemisphere, southern louisiana, southern mississippi, tawny crazy ants, united states, university of texas, videos on youtube

AUSTIN, Texas — Invasive “crazy ants” are displacing fire ants in areas across the southeastern United States, according to researchers at The University of Texas at Austin. It’s the latest in a history of ant invasions from the southern hemisphere and may prove to have dramatic effects on the ecosystem of the region.

The “ecologically dominant” crazy ants are reducing diversity and abundance across a range of ant and arthropod species — but their spread can be limited if people are careful not to transport them inadvertently, according to Ed LeBrun, a research associate with the Texas invasive species research program at the Brackenridge Field Laboratory in the College of Natural Sciences (more…)

How some leaves got fat: It’s the veins

By Guest PostMay 10, 2013Nature2d veins, 3d arrangements, brown university, cross section, dry climate plant, efficient photosynthesis, erika edwards, evolution, evolutionary history, hydraulic path lengths, hydraulics for photosynthesis, leaf vein structure, leaf veins, matt ogburn, molluginaceae, monica arakaki, national science foundation, plump leaves, portulacineae, some plants, succulents, third dimension, venation

Some plants, such as succulents, have managed to grow very plump leaves. For that to happen, according to a new study in Current Biology, plants had to evolve 3-D arrangements of their leaf veins in order to maintain adequately efficient hydraulics for photosynthesis.

PROVIDENCE, R.I. [Brown University] — A garden variety leaf is a broad, flat structure, but if the garden happens to be somewhere arid, it probably includes succulent plants with plump leaves full of precious water. Fat leaves did not emerge in the plant world easily. A new Brown University study published in Current Biology reports that to sustain efficient photosynthesis, they required a fundamental remodeling of leaf vein structure: the addition of a third dimension. (more…)

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