Octavius is, obviously, a female octopus, which is actually a somewhat understandable mistake. Octopuses don’t have strong sexual dimorphism, meaning the sexes don't generally look all that different. The main clues are some minor physical differences on their third right arms that are easily missed. Dumont and his colleagues think Octavius must have been pregnant when she arrived but waited to lay her eggs until she was comfortable in her new home. Octopuses can store semen for weeks after mating in search of optimal conditions.