1 – About three years ago a column in this series appeared about epigenetics (http://blogs.poly.edu/markgreen/2009/09/28/science-from-away-epigenetics-and-%E2%80%9Cinheritance-of-acquired-characteristics%E2%80%9D/), which explained that changes in your life arising from everything from chemicals you are exposed to, to your experiences, can then be passed on to your children. Now, in studies of fruit flies and mice, further experiments demonstrate that these changes are passed on to further generations down the line. I didn’t see any similar experiments on human beings, but it is likely, based on these studies with both insects and mammals, that your life experiences, including environmental hazards and even stressful situations will cause changes in your genetic material to be inherited for the several generations that follow you.
2 – Animals tend to be smaller in warmer regions of the earth. Now scientists studying equid (horses and related animals) body size over a 130,000 year period have discovered that warmer periods in the earth’s history are associated with smaller body sizes while colder periods cause increased body size in the same animal species. However, don’t be concerned or reassured; these things take time, many hundreds to thousands of years.
3 – Tracking pronghorns in Montana, scientists have become convinced that the females of this very fast running horned mammal, pick what the scientists call “genetic studs.” The female appears to recognize which mammal pronghorn has the best genes to pass on to their fawns, which can then survive against the coyotes that prey on the fawn. Most young men, if pressed, will admit that girls decide who they want, not the reverse.
4 – About four years ago two columns appeared in this series about resistance to antibiotics: http://blogs.poly.edu/markgreen/page/9/ http://blogs.poly.edu/markgreen/2007/11/21/resistance-to-antibiotics-part-1/
Overuse of antibiotics seems to be rampant in China with an iconic story about a young man, not trusting the hygiene of the cafeteria for which he worked, popping readily available antibiotic pills after each meal. He died soon after, from an infection, with a body full of “multiple strains of drug-resistant bacteria.” I remember something that happened to me and my family at Peking University. Our son Frank had a fever and it was during the SARS epidemic. Our host was frantic that the whole conference would be quarantined. My wife went to the university store, which sold everything from books to food to pharmaceutics and there on the shelf was Amoxicillin. She bought it, no prescription necessary, and Frank had no fever the next morning. Well, happy ending, but SARS is well understood to be caused by a virus, not a bacterium and therefore the antibiotic had no effect. However, it turns out that in China, doctors give out antibiotics all the time for all kinds of illnesses for which they have no effect while farmers routinely use the drugs on their animals. I just read that the gut microbes of Chinese people have higher numbers of antibiotic bacteria than the citizens of several other countries tested for this.
5 – In an article in the January 20th issue of Science, a report appears entitled: “Bird-Brained Illusionists,” which describes male Great Bachelor Bowerbirds as arranging their bowers (love nests) so that a passing female sees the bower in a most favorable light. To do this they arrange a series of rocks and other objects of different sizes in a way to make the bower seem most uniform from the female’s vantage point. They put larger objects further away. If the rocks and other objects are moved, the male bird quickly rearranges them to restore the illusion. A male bird stands at the opposite end of a bower from the female’s view and carries on displays and vocalizations. Those most successful males get all the “girls,” with their competitors getting no action at all. The article ends with: “Have male bowerbirds mastered the laws of perspective and learned to manipulate them to achieve lascivious ends? I don’t see why the scientists doubt it.”