Science and Medicine

Arkansas Tornadoes Add to Possible April Record

This image, courtesy of the National Weather Service Forecast Office in San Diego, Calif., shows tornado reports April 1-24, 2011 in the central and eastern part of the U.S.

Deadly storms, including reported tornadoes, pounded Arkansas this week, adding to what is likely to be a record tornado count for the month of April.

Four deaths in Arkansas were reported from the severe storms yesterday. If those deaths are attributed to tornadoes, the first four months of 2011 will have matched the tornado death toll for all of last year.

Tornado reports have been pouring into the nation’s Storm Prediction Center in Norman, Okla., and by the time the month comes to an end, it is likely to have set a new April maximum, said the SPC’s Greg Carbin.

The Weather Channel has reported the confirmation of 292 tornadoes in the United States so far this month, besting the previous April record of 267 in 1974. Storm survey teams continue to assess the damage from this month’s storms and could change the number of confirmed tornadoes. The average for April is only 116, according to the SPC.

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Right-Handedness Prevailed 500,000 Years Ago

New research shows that distinctive markings on fossilized teeth correlate to the right or left-handedness of individual prehistoric humans. (Credit: Image courtesy of University of Kansas)

Right-handedness is a distinctively human characteristic, with right-handers outnumbering lefties nine to one. But how far back does right-handedness reach in the human story? Researchers have tried to determine the answer by looking at ancient tools, prehistoric art and human bones, but the results have not been definitive.

Now, David Frayer, professor of anthropology at the University of Kansas, has used markings on fossilized front teeth to show that right-handedness goes back more than 500,000 years. He is the lead author (with colleagues in Croatia, Italy and Spain) of a paper published this month in the British journal Laterality.

His research shows that distinctive markings on fossilized teeth correlate to the right or left-handedness of individual prehistoric humans.

“The patterns seen on the fossil teeth are directly and consistently produced by right or left hand manipulation in experimental work,” Frayer said.

The oldest teeth come from a more than 500,000-year-old chamber known as Sima de los Huesos near Burgos, Spain, containing the remains of humans believed to be ancestors of European Neanderthals. Other teeth studied by Frayer come from later Neanderthal populations in Europe.

“These marks were produced when a stone tool was accidentally dragged across the labial face in an activity performed at the front of the mouth,” said Frayer. “The heavy scoring on some of the teeth indicates the marks were produced over the lifetime of the individual and are not the result of a single cutting episode.”

Overall, Frayer and his co-authors found right-handedness in 93.1 percent of individuals sampled from the Sima de los Huesos and European Neanderthal sites.

“It is difficult to interpret these fossil data in any way other than that laterality was established early in European fossil record and continued through the Neanderthals,” Frayer said. “This establishes that handedness is found in more than just recent Homo sapiens.”

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Study Claims US Meat and Poultry May be Contaminated

Strains of Staphylococcus aureus are present in meat and poultry from US grocery stores at unexpectedly high rates.

Drug-resistant strains of Staphylococcus aureus, a bacteria linked to a wide range of human diseases, are present in meat and poultry from US grocery stores at unexpectedly high rates, according to a nationwide study by the Translational Genomics Research Institute (TGen).

Nearly half of the meat and poultry samples—47 percent—were contaminated with S. aureus, and more than half of those bacteria—52 percent—were resistant to at least three classes of antibiotics, according to the study published April 15 in the journal Clinical Infectious Diseases.

This is the first national assessment of antibiotic resistant S. aureus in the US food supply. And, DNA testing suggests that the food animals themselves were the major source of contamination.

Although Staph should be killed with proper cooking, it may still pose a risk to consumers through improper food handling and cross-contamination in the kitchen.

Researchers collected and analyzed 136 samples—covering 80 brands—of beef, chicken, pork and turkey from 26 retail grocery stores in five U.S. cities: Los Angeles, Chicago, Fort Lauderdale, Flagstaff and Washington, D.C.

Read more: Study Claims US Meat and Poultry May be Contaminated

   

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