Bird homosexuality linked to mercury
01 December 2010, 21:03
Berlin - Exposure to mercury pollution is enough to turn some wild birds gay, researchers have concluded, according to a report in the science journal Nature on Wednesday.
Ecologists in Florida studied the mating behaviour of American white ibises, birds that are not known to engage in same-sex pairings, after exposing them to the hazardous heavy metal.
The researchers used 160 90-day-old nestlings for the study, in which three groups of 20 birds each were fed varying doses of mercury, while a fourth group was given none.
The mercury levels were kept within the range recorded in the wild.
According to Nature, the study found that mercury levels built up in the birds over several years and caused between 13%-15% of nests to produce no offspring - with high number found to be male- male pairings.
Researchers also noted that the ibises that had been exposed to mercury displayed less courtship behaviour.
Higher levels of mercury exposure resulted in an increase in the degree and persistence of homosexual pairing, according to Nature.