What is a baby pufferfish?

Baby dwarf pufferfish are juveniles of the species Carinotetraodon travancoricus or Carinotetraodon imitator. Both species are freshwater pufferfish that reach less than 1 inch in size as adults.

Juvenile dwarf pufferfish are neither male nor female. As the fish get older, they choose their sex based on the other pufferfish in the environment. If two pufferfish begin to become male at the same time, one grows larger and becomes a dominant male. Males produce hormones that prevent other juveniles from becoming male to ensure that there are females available for mating. Adult male dwarf pufferfish are small and colorful, while females are large and drab.