First Dinosaur Bones, Personality Traits and Plankton

• The first dinosaur bones appear to date to about 230 million years ago. This suggests that the fearsome Tyrannosaurus rex, which arrived later, probably evolved from smaller ancestors at least as old this. Archaeologists recently discovered a possible forerunner of T. rex in Argentina. The “new” dinosaur, a lightweight meat-eater named Eodromaeus, was excavated from rock strata about 230 million years old. It was a skinny little beast about the size of a dog, and it resembled T. rex. It stood about four feet tall on long hind legs that appeared to be designed for speed and agility. Its front legs were short and stubby, and were held out front in sort of a “begging” position. With a head, mouth, and teeth like a mini-T. rex, this is not the kind of animal you would like to encounter on a walk with your dog. (Science, Jan. 14, 2011; Science News, Feb. 12, 2011)

• It has been supposed that untreated attention deficit hyperactivity disorder (ADHD) in children can create long-term difficulties as the child grows into adulthood. Therefore, medication is often prescribed in order to allow the ADHD child an opportunity to fit in with peers and concentrate on learning.

To test the supposition that ADHD children grow into ADHD adults, two scientists at Columbia University and New York State Psychiatric Institute studied the records of 1,500 children who had been diagnosed as ADHD based on accepted diagnostic procedures. They found that after two years many of the children originally diagnosed as ADHD no longer met the diagnostic criteria. ADHD is divided into three subtypes: hyperactive, inattentive, and both combined. More than half of the hyperactive and inattentive subtypes showed no ADHD symptoms after a two-year follow-up. The combined subtype group showed that 18-35 percent were no longer ADHD.

More research needs to be done, but this study gives hope that in many cases children outgrow the condition. This does not mean that young children diagnosed with ADHD should not receive medication, for they need to be able to concentrate when appropriate and learn to interact with other children in a normal manner. Later, it’s possible the medication can be withdrawn as the ADHD symptoms diminish. (Scientific American Mind, March/April 2011)

• Dana Carney of Columbia University evaluated and compared five personality traits of people in two groups: those in one group considered themselves liberal and those in the other group considered themselves conservative or even right wing. The five traits were openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism. In general, the conservative group tended to be more conventional, orderly, organized, neat, clean, withdrawn, reserved, and rigid. The liberal group tended to be more open, tolerant, creative, curious, expressive, enthusiastic, and drawn to novelty and diversity. (Scientific American Mind, March/April 2011)

• How important is plankton? Plankton consists of microscopic plants and animals that form the foundation of all aquatic food chains. These organisms drift along on currents in oceans and lakes. If all plankton in the oceans died, all sea life would soon follow, since plankton is the foundation of the aquatic food chain. The loss of plankton would also lead to a loss of about half the oxygen in our atmosphere. Use your imagination to ponder what would happen to man if the amount of atmospheric oxygen were cut in half.

• In our brain there’s a neurotransmitter, or chemical messenger, called dopamine. The release of this chemical by neurons is associated with motivation, pleasure, movement, and learning. Studies show that in fall and winter, the level of dopamine is somewhat lower than in spring and summer. Does this surprise you? (Journal of Neuroscience, November 3, 2010)