The platypus, which is native to Australia, is a one-of-a-kind mammal with webbed feet for swimming and a beak for hunting underwater. Despite being a mammal, it lays eggs and can walk on land as well as swim in freshwater.
Penguins are flightless birds with excellent swimming abilities. They are fast swimmers who travel on land using their flipper-like wings.
Crocodiles are good swimmers and are frequently seen in aquatic environments. They walk or crawl on earth using their strong limbs. They are equally at ease in both settings.
Sea lions are aquatic creatures famed for their agility. They can "walk" in a gallop-like fashion on land by using their enormous flippers.
Otters are both lively and nimble on land and in the water. They have webbed feet and streamlined bodies for effective swimming, as well as the ability to move easily on land.
Marine iguanas are well-known for their ability to swim in the ocean and can be found in the Galápagos Islands. They have flattened tails that allow them to swim efficiently and sharp claws that allow them to grip rocks on land.
Ducks are adaptable birds that can walk on land as well as swim in water. They walk with a unique waddle and have webbed feet for paddling in the water.
The semi-aquatic caiman lizard is native to South America. It has keen claws for climbing trees and a slender tail for swimming in rivers and streams.
The ability of some tortoise species, such as the Galápagos tortoise, to travel between terrestrial and aquatic habitats is well recognized. They are capable of swimming and navigating in shallow water.
Hippos are well adapted to both land and water activities, including swimming in rivers and lakes. They are remarkably nimble in the water, despite their big size.