Some machines also added a third or fourth flipper midway up the playfield. The hawksbill's forelimbs have two visible claws on each flipper. Both the flipper and the fin are for stabilization and steering in the water. The Florida manatee has three to four nails on each flipper. The forelimb thus develops into a flipper. Basilosaurus did still have an elbow joint in its flipper like a seal. Other sites of placement depend on species and may include the flipper or tail. The series was often characterised as a kangaroo version of Flipper or Lassie. Common bottlenose dolphins are popular in aquarium shows and television programs such as "Flipper". Bottlenose dolphins gained popularity from aquarium shows and television programs such as "Flipper". Dugongs have two teats, one located behind each flipper. It contains the movie in two formats on a flipper disc. Often, the rear flipper is only half the length of the front flipper. Male forms of courtship behavior include nuzzling, biting, and head and flipper movements. The original script featured Jerry watching the TV series "Flipper".