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Fossil Reveals Oldest Evidence of Live Birth in Reptiles

By Guest PostJuly 22, 2011Sciencehungry dinosaur, live birth, oldest evidence, pregnant lizard, squamate reptiles

A fossil from north-eastern China has revealed that terrestrial reptiles were giving birth to live young at least as early as 120 million years ago

The newly discovered fossil of a pregnant lizard proves that some squamate reptiles (lizards and snakes) were giving birth to live young, rather than laying eggs, in the Early Cretaceous period – much earlier than previously thought. The fossil shows a pregnant female filled with the tiny skeletons of more than 15 baby lizards at a stage of development similar to that of late embryos of modern lizards. The mother lizard, which is 30 centimetres long (excluding her tail), probably died only a few days before giving birth. (more…)

Border Fences Pose Threats to Wildlife on U.S.-Mexico Border, Study Shows

By Guest PostJuly 19, 2011Nature, Sciencearroyo toad, biological diversity, border fences, california coasts, california red legged frog, conservation, department of homeland security, fire, harmful mutations, human impacts, human migration barriers, human population growth, hurricane, impacts on the ecosystem, inbreeding depression, jesse lasky, landscape, species in california, texas gulf, the jaguarondi, the university of texas at austin, threats to wildlife populations, tim keitt, unforeseen disturbances, us mexico border, walter jetz

AUSTIN, Texas — Current and proposed border fences pose significant threats to wildlife populations, with those animals living in border regions along the Texas Gulf and California coasts showing some of the greatest vulnerability, a new study from The University of Texas at Austin shows.

“Our study is the first comprehensive analysis of threats to species across the entire U.S.-Mexico border,” says Jesse Lasky, a graduate student in the laboratory of Tim Keitt, associate professor of integrative biology. “The scale at which these fences stretch across the landscape is large, so it’s important for us to also have a large-scale view of their effects across the continent.” (more…)

Where the Earth’s Heat Comes From

By Guest PostJuly 18, 2011Scienceearth heat, geoneutrino signal, heat flow, inner earth, kamland detector, radioactive sources

Berkeley Lab scientists join their KamLAND colleagues to measure the radioactive sources of Earth’s heat flow

What spreads the sea floors and moves the continents? What melts iron in the outer core and enables the Earth’s magnetic field? Heat. Geologists have used temperature measurements from more than 20,000 boreholes around the world to estimate that some 44 terawatts (44 trillion watts) of heat continually flow from Earth’s interior into space. Where does it come from? (more…)

Making Blood-Sucking Deadly for Mosquitoes

By Guest PostJuly 17, 2011Scienceaedes aegypti, biochemical processes, blood feeding, blood meal, cellular process, coatomer protein 1, copi, copi system, dengue fever, dengue hemorrhagic fever, dengue viruses, digestive enzymes, egg production cycle, jun isoe, molecular process cells, mosquitoes, protein complex, proteins, rnai, roger miesfeld, secretion of enzymes, sub tropical, tablespoons of sugar, the university of arizona, toolbox, tropical regions of africa, vesicle transport, warm blooded animals

*Inhibiting a molecular process cells use to direct proteins to their proper destinations causes more than 90 percent of affected mosquitoes to die within 48 hours of blood feeding, a UA team of biochemists found.*

Mosquitoes die soon after a blood meal if certain protein components are experimentally disrupted, a team of biochemists at the University of Arizona has discovered.

The approach could be used as an additional strategy in the worldwide effort to curb mosquito-borne diseases like dengue fever, yellow fever and malaria. (more…)

NASA’s Dawn Spacecraft Enters Orbit Around Asteroid Vesta

By Guest PostJuly 17, 2011Scienceasteroid, asteroid vesta, ceres, charles bolden, dawn, dawn spacecraft, dwarf planet, german aerospace center, gravitational pull, gravity, italian space agency, jet propulsion laboratory, los angeles, main asteroid belt between mars and jupiter, marshall space flight center in huntsville, max planck institute for solar system research, NASA, President Obama, spacecraft, university of california, vesta

PASADENA, Calif. — NASA’s Dawn spacecraft on Saturday became the first probe ever to enter orbit around an object in the main asteroid belt between Mars and Jupiter.

Dawn will study the asteroid, named Vesta, for a year before departing for a second destination, a dwarf planet named Ceres, in July 2012. Observations will provide unprecedented data to help scientists understand the earliest chapter of our solar system. The data also will help pave the way for future human space missions. (more…)

Is Meditation the Push-up for the Brain?

By Guest PostJuly 16, 2011Health, Scienceage related brain atrophy, amygdale, anterior corpus callosum, axonal demyelination, brain imaging, brain regions, brain stem, brains, bundles of neurons, cerebral cortex, corticospinal tract, diffusion tensor imaging, dti, eileen luders, electrical signals in the brain, frontal cortex, hippocampus, immune system, kristi clark, limbic system, meditation, meditators, mental exercise, micro anatomical level, occipital lobes, physical structure of the brain, shamatha, spinal cord, superior longitudinal fasciculus, uncinate fasciculus, vipassana, white matter, zazen

*Study shows practice may have potential to change brain’s physical structure*

Two years ago, researchers at UCLA found that specific regions in the brains of long-term meditators were larger and had more gray matter than the brains of individuals in a control group. This suggested that meditation may indeed be good for all of us since, alas, our brains shrink naturally with age.

Now, a follow-up study suggests that people who meditate also have stronger connections between brain regions and show less age-related brain atrophy. Having stronger connections influences the ability to rapidly relay electrical signals in the brain. And significantly, these effects are evident throughout the entire brain, not just in specific areas. (more…)

Astronomer Tom Gehrels, 1925-2011

By Guest PostJuly 14, 2011Scienceasteroids and comets, astronomer, astronomy, Britain, Chicago, dutch resistance, earth, England, gerard p kuiper, haarlemmermeer, harold masursky award, imaging photopolarimetry, jupiter, kitt peak, leiden university, nobel astrophysicist, saturn, saturn mysterious f ring, special operations executive, study of wavelength dependence of polarization of stars and planets, subrahmanyan chandrasekhar, the netherlands, tom gehrels, universal evolution, university of arizona, university of chicago

*In a career that spanned more than half a century, Gehrels fostered new research on asteroids and comets, including those that pose a threat to Earth.*

Tom Gehrels, an internationally noted planetary scientist and astronomer at the University of Arizona, as well as a hero of the Dutch Resistance during WWII, died Monday. He was 86.

Gehrels was among the first members of the fledgling Lunar and Planetary Laboratory when he joined the UA in 1961. During a long and distinguished career Gehrels pioneered new research on asteroids and comets, especially those that pose a collision threat to Earth. He also developed and taught introductory astronomy courses that were popular with non-science undergraduates. (more…)

Last Dinosaur Before Mass Extinction Discovered

By Guest PostJuly 13, 2011Scienceage of dinosaur, fossilized horn, last dinosaur, mass extinction, non avian dinosaurs

A team of scientists has discovered the youngest dinosaur preserved in the fossil record before the catastrophic meteor impact 65 million years ago. The finding indicates that dinosaurs did not go extinct prior to the impact and provides further evidence as to whether the impact was in fact the cause of their extinction. (more…)

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