#aquatic_mammal__aquaticmammal  whales and dolphins; manatees and dugongs; walruses; seals
  supertype:  #placental_mammal__placentalmammal__placental__eutherian__eutherian_mammal__eutherianmammal  mammals having a placenta; all mammals except monotremes and marsupials
  subtype:  #cetacean_mammal  #sea_cow  #pinniped_mammal
  part:  #flipper  the flat broad limb of aquatic animals specialized for swimming

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