Papuan cuttlefish (Sepia papuensis), courtship. Male cuttlefish compete for dominance and the best den during mating season. The successful male cuttlefish clasps the female with its tentacles and uses a specialized tentacle to insert a sperm sac into an opening near the female's mouth. The male then guards the female until she lays her eggs a few hours later. Photographed in West Papua, Indonesia.