NEW YORK TIMES: A discovery like Young’s can disorient a wildlife biologist in the most thrilling way — if he or she takes it seriously, which has traditionally not been the case. Various forms of same-sex sexual activity have been recorded in more than 450 different species of animals by now, from flamingos to bison to beetles to guppies to warthogs. A female koala might force another female against a tree and mount her, while throwing back her head and releasing what one scientist described as “exhalated belchlike sounds.” Male Amazon River dolphins have been known to penetrate each other in the blowhole. Within most species, homosexual sex has been documented only sporadically, and there appear to be few cases of individual animals who engage in it exclusively. For more than a century, this kind of observation was usually tacked onto scientific papers as a curiosity, if it was reported at all, and not pursued as a legitimate research subject. Biologists tried to explain away what they’d seen, or dismissed it as theoretically meaningless — an isolated glitch in an otherwise elegant Darwinian universe where every facet of an animal’s behavior is geared toward reproducing. One primatologist speculated that the real reason two male orangutans were fellating each other was nutritional. MORE