Greg Bear's Nebula Award-winning novel, Darwin's Radio, painted a chilling portrait of humankind on the threshold of a radical leap in evolution-one that would alter our species forever. Now Bear continues his provocative tale of the human race confronted by an uncertain future, where 'survival of the fittest' takes on astonishing and controversial new dimensions. DARWIN'S CHILDRENEleven years have passed since SHEVA, an ancient retrovirus, was discovered in human DNA-a retrovirus that caused mu