The history of six large herbivores -- the woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison, and musk ox -- is the subject of a study by an international group of scientists investigating how climate fluctuations and human activity affected mammal populations at the end of the last ice age. According to Beth Shapiro, the Shaffer Associate Professor of Biology at Penn State University and a member of the research team, both climate change and humans were responsible for the extinction of some cold-adapted animals and the near extinction of others.
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ROCHESTER, Minn. — Mayo Clinic researchers have discovered why measles, perhaps the most contagious viral disease in the world, spreads so quickly. The virus emerges in the trachea of its host, provoking a cough that fills the air with particles ready to infect the next host. The findings may also help in the fight against ovarian, breast and lung cancers.
Honey bee populations have been mysteriously falling for at least five years in the United States, but the cause of so-called colony collapse disorder (CCD) is still largely unknown.
In a report published Nov. 2 in the online journal PLoS ONE, researchers report that a widely used in-hive medication may make bees more susceptible to toxicity of commonly used pesticides, and that this interaction may be at least partially responsible for the continuing honey bee population loss.
ROCHESTER, Minn. -- Researchers at Mayo Clinic (http://www.mayoclinic.org) have shown that eliminating cells that accumulate with age could prevent or delay the onset of age-related disorders and disabilities. The study, performed in mouse models, provides the first evidence that these "deadbeat" cells could contribute to aging and suggests a way to help people stay healthier as they age.
A piece of jawbone excavated from a prehistoric cave in England is the earliest evidence for modern humans in Europe, according to an international team of scientists. The bone first was believed to be about 35,000 years old, but the new research study shows it to be significantly older -- between 44,000 and 41,000 years old, according to the findings that will be published in the journal Nature. The new dating of the bone is expected to help scientists pin down how quickly the modern humans spread across Europe during the last Ice Age.
The timing, process and archeology of the peopling of Europe by early modern humans have been actively debated for more than a century. Reassessment of the anatomy and dating of a fragmentary upper jaw with three teeth from Kent's Cavern in southern England has shed new light on these issues.
Originally found in 1927, Kent's Cavern and its human fossil have been reassessed by an international team, including Erik Trinkaus, PhD, professor of anthropology in Arts & Sciences at Washington University in St. Louis, and the results published in Nature.
Members of our species (Homo sapiens) arrived in Europe several millennia earlier than previously thought. At this conclusion a team of researchers, led by the Department of Anthropology, University of Vienna, arrived after re-analyses of two ancient deciduous teeth. These teeth were discovered 1964 in the "Grotta del Cavallo", a prehistoric cave in southern Italy. Since their discovery they have been attributed to Neanderthals, but this new study suggests they belong to anatomically modern humans.
Smithsonian scientists and colleagues conducted the first DNA barcoding survey of crustaceans living on samples of dead coral taken from the Indian, Pacific and Caribbean oceans. The results suggest that the diversity of organisms living on the world's coral reefs is seriously underestimated. The team's research "The Diversity of Coral Reefs: What Are We Missing?" was published in October in the journal PLoS ONE.
COLLEGE STATION -- Did climate change or humans cause the extinctions of the large-bodied Ice Age mammals (commonly called megafauna) such as the woolly rhinoceros and woolly mammoth?
CORVALLIS, Ore. – One of the most comprehensive analyses yet done of the ancient history of insect-borne disease concludes for the first time that malaria is not only native to the New World, but it has been present long before humans existed and has evolved through birds and monkeys.
The findings, presented in a recent issue of American Entomologist by researchers from Oregon State University, are based on the study of insect specimens preserved in amber.
The first genome-scale model for predicting the functions of genes and gene networks in a grass species has been developed by an international team of researches that includes scientists with the U.S. Department of Energy (DOE)'s Joint BioEnergy Institute (JBEI), a multi-institutional partnership led by Lawrence Berkeley National Laboratory (Berkeley Lab).
MANHATTAN, Kan. -- The source of arsenic in India's groundwater continues to elude scientists more than a decade after the toxin was discovered in the water supply of the Bengal delta in India. But a recent study with a Kansas State University geologist and graduate student, as well as Tulane University, has added a twist -- and furthered the mystery.
Cold Spring Harbor, N.Y. – Cancer cells maintain their life-style of extremely rapid growth and proliferation thanks to an enzyme called PK-M2 (pyruvate kinase M2) that alters the cells' ability to metabolize glucose – a phenomenon known as the Warburg effect.
BUFFALO, N.Y. -- Exenatide, a drug commonly prescribed to help patients with type 2 diabetes improve blood sugar control, also has a powerful and rapid anti-inflammatory effect, a University at Buffalo study has shown.
The study of the drug, marketed under the trade name Byetta, was published recently in the Journal of Clinical Endocrinology and Metabolism.
AUGUSTA, Ga. – Examining the chin and upper and lower abdomen is a reliable, minimally invasive way to screen for excessive hair growth in women, a key indicator of too much male hormone, researchers report.
"We wanted to find a way to identify this problem in women that was as non-intrusive and accurate as possible," said Dr. Ricardo Azziz, reproductive endocrinologist and President of Georgia Health Sciences University.