Berlin - A leading German magazine reported on Friday that researchers have found a certain type of fly can show homosexual tendencies when temperatures are increased above 30°C.

The monthly natural science magazine Geo said researchers at the Beckman Research Institute in Los Angeles had found the fruit fly, drosophila melanogaster, had developed a "homosexual preference" when the laboratory temperature was increased from about 19 degrees to above 30 degrees.

"The male flies displayed clear heterosexual activities when temperatures were at 19 degrees, but above 30 degrees their behaviour changed within minutes," the report in the December issue of Geo released on Friday said.

"The male flies ignored the female partners at that point and chased after their male counterparts. As soon as the temperature was reduced again, they returned to their original behaviour."

The fruit fly, which is about 3mm long, typically accumulates around spoiled fruit. It is one of the most valuable organisms in biological research, particularly in genetics and developmental biology.