FEMALE LIZARDS CHOOSY ABOUT HOME, MATES
In many species females are very picky about where they call home and who they bring home as a mate. University of California-Los Angeles researchers, writing in the Proceedings of the National Academy of Sciences, say they are studying the fitness choices female blotched lizards make and note while the ladies prefer improved territories in which to live, they still select high-quality sires for their offspring. They say having better digs is associated with earlier egg-laying dates, larger eggs and an enhanced competitive ability -- meaning youngsters are more likely to directly benefit from living in a better neighborhood. The females also show a preference for large males and are very dominant in the mating system. They are selective, however, using sperm from large sires to produce sons and sperm from smaller sires to produce daughters.

EARLY MAN DIDN'T THROW SPEAR
Early man knew how to make a spear -- he just didn't know how to throw it and therefore had a limited hunting strategy of stabbing trapped animals. The first direct evidence of thrown spears dates back 19,000 years but an analysis of arm bones of Neanderthals, who lived between 230,000 and 30,000 years ago, finds they were much stronger in one arm than the other -- suggesting they threw spears. Duke University researchers writing in New Scientist disagree, noting a two-handed spear thrust puts far more stress on the dominant arm holding the back end of the spear than the front arm. The researchers measured Neanderthal humerus bones, showing they were thicker front to back than side to side -- indicative of a thrusting motion. Later humans who used spears had rounder humeri, suggesting throwing a spear distributes force relatively evenly. In thrusting vs. throwing experiments, volunteers generated 70 percent more force thrusting with the dominant back arm than with the front arm. In extreme cases, the force on one arm was six times that on the other.

MALE WASPS USE CHEMICALS TO FIND MATES
Male wasps have a unique buddy system, using changes in plant chemicals to leave messages to their successors telling them where potential mates are located. Researchers at the University of Illinois at Urbana-Champaign say each spring, amid the decaying rubble of dead prairie plants, emerging male gall wasps find mates by looking for these chemistry clues left behind. As adult male wasps feed in warm weather, they change the ratio of plant chemicals. The researchers say it is very interesting because the females are inside the plant stems and not producing pheromones, so it is a plant's volatile chemicals that attract the males. Once a male finds a site with a mate he will defend it -- head-butting other males away from his turf.