Parapercis cylindrica a species of reef perch used in the study. Researchers found that its ear bones change in growth when it undergoes a sex change from female to male.
Credit: ARC COE
"We can use these short-lived 'model species' with daily otolith growth patterns, to tease apart the relationships between sex change, and other key life history attributes, like growth and lifetime fecundity," the authors write. "[And also] determine the relative amount of time individuals spend as female and male, and how this ratio varies, both naturally and in response to fishing pressure."
Walker and McCormick also have a theory that the larger and different shaped ear-stones in male perches may have something to do with the fine tuning of the fishes' spatial perception. Like humans, the inner ears of fish are not only receptive to sound, but are also receptive to individual movement and orientation.
Sex changing fish may also change their otolith development so as to become more proficient in their new reproductive mode, which often involves moving around more complex terrain and engaging in physical combat with other males associated with competition for female partners.
With the ARC Centre of Excellence for Coral Reef Studies
