Dr. J. Lee Nelson from the Fred Hutchinson Cancer Research Centre in Seattle has shown that fetal cells can persist in their mothers after birth and may confuse the immune system into attacking itself. The Search for Water on Mars Listen to MP3 Dr. Jeffrey Plaut , a research scientist at NASA s Jet PropulsionLaboratory in Pasadena, California, has a plan to search for water onMars, using new instruments on upcoming missions to the Red Planet. Agency'sMars Express orbiter in 2003. In the long history of human evolution, one of the most importantturning points was the change from hunting and gathering our food toherding and farming it. It was that change that led directly to thedevelopment of civilization, cities, and culture.
Scientists know the key to that change was the domestication of wildanimals and crops.
And they know it happened first in the area of theMiddle East known as the Fertile Cresent. Now Dr. Melinda Zeder thinks she s found a few clues in some old goat bones that reveal how and when it occurred. Dr. Zeder is the curator of Old World Archaeology at the SmithsonianInstitution s National Museum of Natural History in Washington. And that s raised expectations that the average humanlifespan could go up to 100 - or even, some say, to 150. But not according to Dr. Jay Olshanky .