Science & Society
In Brief |h 1 : How the big guys bulked up
Talk about packing on the pounds. Gregory Erickson of Florida State University and his colleagues have found that young dinosaurs could gain as much as 35 pounds a day. That's as fast as whales--the current growth champs--underscoring how different dinosaurs were from today's slow-growing reptiles.
At a paleontology meeting in St. Paul last month, Erickson's colleague Kristi Curry Rogers of the Science Museum of Minnesota reported that the group had found a way to convert changes in thigh-bone length into growth charts for immature dinosaurs. "We've cracked the code," says Erickson. Even the smallest dinosaurs grew at least twice as fast as modern-day reptiles, they found, and the biggest ones grew 56 times as fast--fast enough for an apatosaurus (aka brontosaur) to have reached full size in 10 to 15 years. -Emily Sohn
In Brief |h 1 : Calm Is A Balm
Don't sweat the surgery: Worrying just makes healing harder. In a study in Psychosomatic Medicine, researchers gave questionnaires to nearly 50 hernia patients before surgery, asking how worried they were. Those who were most worried had low levels of an immune system messenger called IL-1 and an enzyme called MMP9, which prepares the wound site for healing. After surgery, the worried patients reported more pain and thought it would take longer before they felt normal again.
All this hints that psychological treatments like relaxation training might speed recovery. They might also help with the stress of bills and insurance headaches. -Josh Fischman
In Brief |h 1 : Regular Flossing
On a recent picnic, anthropologist Leslea Hlusko watched a friend use a piece of grass as a toothpick. It reminded her of an old mystery--the odd grooves seen on teeth in hominid skulls as much as 2 million years old. Many experts guessed that the grooves came from toothpicking or flossing, but modern toothpicks don't create the same wear marks. "Grass stalks seemed like the perfect answer," thought Hlusko, who is at the University of Illinois. She tried stalks on teeth in human and baboon skulls. Grasses contain abrasive minerals, and after a few hours of rubbing, they reproduced the grooves exactly, she reports in Current Anthropology. Picking our teeth, she writes, could be "the most persistent habit documented in human evolution." -Nell Boyce
In Brief |h 1 : Spending A Legacy
Think gas is steep at $1.50 a gallon? Look at it this way: That $1.50 buys almost 100 tons of ancient plants, ecologist Jeffrey Dukes says in this month's Climatic Change.
Today's oil fields formed as microscopic plants living in ancient seas died and sank, then were buried deeply enough for heat and pressure to cook the organic matter into oil. At each step, much of the original material decayed or escaped. Dukes, then at the University of Utah, used published figures to calculate that every day, humanity burns up oil equivalent to nearly a year's worth of plant growth across the entire planet. "It is a soberingly large number," remarks oceanographer Richard Keil of the University of Washington--and suggests a gallon of regular is more precious than it seems. -Tim Appenzeller
This story appears in the November 10, 2003 print edition of U.S. News & World Report.
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