Touch or smell - what triggers sex change in sea snails?
March 25, 2013
Before a pair of slipper limpet sea snails can get in the mood to reproduce, one of them has to change sex
Before a pair of slipper limpet sea snails can get in the mood to reproduce, one of them has to change sex. Scientists have long known these saltwater critters begin their lives as males but researchers still want to know what flips the gender switch.
Physical contact between reproduction-ready snails is one obvious trigger. But water-borne chemicals are common signals in marine environments. So STRI scientist Rachel Collin and intern Allan Carrillo designed an experiment to see if chemical or physical signals regulate sex change.
Allan, from the University of Costa Rica, placed pairs of male Crepidula marginalis in treatments where they shared the same water. In one treatment, they were separated by a screen, making physical contact impossible.
The larger snail always changed sex first. But in the treatments with screens, the smaller snail changed sex sooner than the smaller snail that had physical contact with the larger male.
“Physical contact inhibits the small males from changing sex in the ‘together' treatment,” says Allan, who presented a poster of his work at STRI's Fellows and Interns Symposium on March 15.
“This project is something that I've wanted to do for a long time and I'm really exited that Allan got such an unexpected result,” says Rachel, adding she expected water-bourne chemical signals to mediate sex change.