After clownfish hatch from their eggs in the ocean, they spend about 10 to 12 days floating freely in the ocean as larvae. After that time, they often return to the reefs close to the shore where they were born. The way they find their way back home has long been a mystery.
Researchers studying the percula clownfish have recently found that the clownfish may be attracted to the smells in the seawater. In a recent study, scientists showed that clownfish were attracted to water samples treated with anemones or leaf litter over other control sample scents. This suggests that scent or other chemical markers in the water are what allow the fish to find their way home. This is the first time that terrestrial causes of scent, such as leaf litter, have been considered.
(Published online http://journals.royalsociety.org)
