Swallows are getting sexier. Male barn swallows attract females with long tail feathers, and European researchers have observed that over the last 20 years those feathers have become much longer. "We've demonstrated quite a dramatic change in a short period of time," said Dr. Anders Pape Moller, an evolutionary biologist at Pierre and Marie Curie University in Paris, who conducted the research with Dr. Tibor Szep of the College of Nyiregyhaza in Hungary. The findings are to be published in The Journal of Evolutionary Biology. Advertisement Experiments suggest that the males' tails act as advertising for good genes because males...