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Russian Dolls of the Bug World

By Guest PostMarch 1, 2012Scienceacyrthosiphon pisum, aphid alarm pheromone, aphidius ervi, aphids, apse, bacteriophage, bacterium, battle for survival, environmental sciences, Europe, hamiltonella defense, hemolymph, insect, kerry oliver, martha molly hunter, North America, parasite and host, parasitic wasps, pea aphid, russian dolls, symbiont, trans b farnesene, university of arizona, virus, wasp larva

Parasitic wasps using tiny insects known as aphids as living nurseries for their brood can sniff out whether the host insect is protected by symbiotic bacteria, researchers have discovered.

A research team including Martha (Molly) Hunter from the department of entomology in the University of Arizona’s College of Agriculture of Life Sciences has disentangled relationships in an assembly of players that resemble Russian dolls: a bacterium that lives inside a tiny insect, a virus that infects those bacteria, and a parasitic wasp that lays its eggs in the insect.

In a war between parasite and host, the parasitic wasp, Aphidius ervi, and the pea aphid, Acyrthosiphon pisum, are locked in a battle for survival. (more…)

When Continents Collide: A New Twist To a 50 Million-Year-Old Tale

By Guest PostMarch 1, 2012Scienceearth, earthquakes, eurasia, fifty million years, geological activity, geological history, geology, geomorphologist, geophysicist, highest mountain, himalaya mountains, India, indian plate, indian sub continent, jim erickson, marin clark, mountain building episode, northern india, northern tibet, plate boundaries, plate tectonics, post collisional motion, the himalaya, theory, tibet, tibetan plateau, university of michigan, volcanoes

ANN ARBOR, Mich.— Fifty million years ago, India slammed into Eurasia, a collision that gave rise to the tallest landforms on the planet, the Himalaya Mountains and the Tibetan Plateau.

India and Eurasia continue to converge today, though at an ever-slowing pace. University of Michigan geomorphologist and geophysicist Marin Clark wanted to know when this motion will end and why. She conducted a study that led to surprising findings that could add a new wrinkle to the well-established theory of plate tectonics – the dominant, unifying theory of geology. (more…)

Solving a Spintronic Mystery:

By Guest PostFebruary 29, 2012Scienceberkeley lab, charge carriers, curie temperature, electron acceptors, electronic states, fermi level, ferromagnetic properties, gallium, gallium arsenide, gallium manganese arsenide, jacek furdyna, kin man yu, magneto optical data, margaret dobrowolska, mona berciu, rutherford backscattering facility, semiconductor, silicon, spin, spintronic devices, spintronic potential, spintronic technology, university of notre dame, valence energy band, wladek walukiewicz, xinyu liu

*Berkeley Lab Researchers Resolve Controversy Over Gallium Manganese Arsenide that Could Boost Spintronic Performance*

A long-standing controversy regarding the semiconductor gallium manganese arsenide, one of the most promising materials for spintronic technology, looks to have been resolved. Researchers with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) in collaboration with scientist from University of Notre Dame have determined the origin of the charge-carriers responsible for the ferromagnetic properties that make gallium manganese arsenide such a hot commodity for spintronic devices. Such devices utilize electron spin rather than charge to read and write data, resulting in smaller, faster and much cheaper data storage and processing. (more…)

Ice Age Mariners From Europe Were Among America’s First People

By Guest PostFebruary 29, 2012Scienceacross atlantic ice, alaska, america, asia, bering sea, Berkeley, boat, bruce bradley, cities of gold, clovis, clovis culture, dennis stanford, douglas preston, earliest humans, Europe, last ice age, native americans, new mexico, new world, North America, northern spain, orthodoxy, paradigm, sea ice shelf, smithsonian institution, solutrean people, thunderhead, united states, university california press, university of exeter

Some of the earliest humans to inhabit America came from Europe according to a new book.

Across Atlantic Ice puts forward a compelling case for people from northern Spain travelling to America by boat, following the edge of a sea ice shelf that connected Europe and America during the last Ice Age, 14,000 to 25,000 years ago.

Across Atlantic Ice is the result of more than a decade’s research by leading archaeologists Professor Bruce Bradley of the University of Exeter and Dr Dennis Stanford of the Smithsonian Institution. Through archaeological evidence, they turn the long-held theory of the origins of New World populations on its head.

For more than 400 years, it has been claimed that people first entered America from Asia, via a land bridge that spanned the Bering Sea. We now know that some people did arrive via this route nearly 15,000 years ago, probably by both land and sea. (more…)

Molecular Duo Dictate Weight and Energy Levels, Yale Researchers Find

By Guest PostFebruary 29, 2012Scienceanthony van den pol, bill hathaway, brain control, cells, cellular mechanism, energy, energy balance, hypothalamic neurons, hypothalamus, journal of neuroscience, mch, melanin concentrating hormone, nervous system, neurons, neurotransmitter, thyrotropin releasing hormone, trh, xiaobing zhang, yale university

Yale University researchers have discovered a key cellular mechanism that may help the brain control how much we eat, what we weigh, and how much energy we have.

The findings, published in the Feb. 28 issue of the Journal of Neuroscience, describe the regulation of a family of cells that project throughout the nervous system and originate in an area of the brain call the hypothalamus, which has been long known to control energy balances. (more…)

Coyotes “Shrank,” Wolves Did Not, After Last Ice Age and Megafaunal Extinctions

By Guest PostFebruary 28, 2012Nature, Sciencebergmann rule, coyote morphology, coyotes, ecogeographic principle, gray wolf, pleistocene coyotes, skeletons of wolves, solitary predators

*Once large and wolf-like, coyotes ultimately became much smaller*

When the last ice age ended more than 10,000 years ago, many large species of mammals went extinct and others underwent changes in appearance. (more…)

New Book Details Archaeological Excavations on San Juan Island

By Guest PostFebruary 28, 2012Sciencearchaeological excavations, english camp, san juan island

It’s a powerful feeling, says anthropology graduate student Amanda Taylor, to stand where people stood thousands of years back and gaze out at the same water — the same sunsets — that they saw so long ago. (more…)

Hyperactivity in Brain May Explain Multiple Symptoms of Depression

By Guest PostFebruary 28, 2012Health, Scienceabnormal patterns, abnormal rhythms, aimee m hunter, andrew leuchter, brain chemistry, brain dysfunction, brain networks, brain regions, brain waves, chaochao cai, connection, depressed brain, depression, electrical activity, electrical signal, function, ian a cook, lilly research laboratories, major depressive disorder, mark wheeler, mdd, pfizer pharmaceuticals, steve horvath, symptoms, synchronization, ucla

*Electrical signals can’t shut off, suggest UCLA researchers*

Most of us know what it means when it’s said that someone is depressed. But commonly, true clinical depression brings with it a number of other symptoms. These can include anxiety, poor attention and concentration, memory issues, and sleep disturbances.

Traditionally, depression researchers have sought to identify the individual brain areas responsible for causing these symptoms. But the combination of so many symptoms suggested to UCLA researchers that the multiple symptoms of depression may be linked to a malfunction involving brain networks — the connections that link different brain regions. (more…)

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