High temperatures can affect the sex of common carp. Researchers found that exposing carp larvae to high temperatures for 7 days shortly after hatching can make them more likely to become male. The critical period for this effect is between 7 and 13 days after hatching. Even when exposed to high temperatures as juveniles, the carp still showed a higher percentage of males. This shows that the environment can strongly influence the sex of common carp, even before their sex organs fully develop.