Spotting Good Genes

What should a lioness searching for a mate look for? If she wants a partner with robust genes, she might do well to check out the pattern of whisker spots on her suitor's face. So say a pair of University of Minnesota researchers in a report in the journal Nature. After examining whisker patterns on 920 lions, they concluded that males whose black dots in the topmost row of whiskers line up evenly tended to have longer lives than lions whose spots are arranged in a more irregular fashion.

The findings buttress a new biological theory proposing that all sorts of small variations in symmetrical features, such as fish fins and birds' forked tails, are signals of genetic stress. For some unexplained reason, lionesses don't fit the theory -- in fact, females with uneven whisker spots lived longer.