What is the Difference Between Aquatic and Terrestrial Animals?

The main difference between aquatic and terrestrial animals lies in their habitats and how they adapt to them. Aquatic animals live predominantly or entirely in the water, while terrestrial animals live predominantly or entirely on land. Here are some key differences between the two:

Habitat:

Aquatic animals can be found in water habitats, such as ponds, lakes, streams, rivers, and wetlands.
Terrestrial animals can be found exclusively on land, in habitats such as forests, taiga, tundra, and deserts.

Respiration:

Aquatic animals usually respire through gills, which are organs specifically adapted for extracting oxygen from water.
Terrestrial animals usually respire through lungs, which are organs specifically adapted for extracting oxygen from the air.

Skin:

Aquatic animals typically have slimy, slippery, and soft skin that helps them move efficiently in water.
Terrestrial animals often have leathery, hard, or spiny skin that provides protection and insulation.

Locomotion:

Aquatic animals often have fins, flippers, or other specialized structures for movement in water.
Terrestrial animals usually have legs, wings, or other specialized structures for movement on land.

However, some animals, such as penguins, seals, and walruses, spend part of their life in water and part on land, making it difficult to label them strictly as aquatic or terrestrial. Additionally, some groups of insects, like mosquitoes and dragonflies, are partially aquatic, complicating the distinction between aquatic and terrestrial animals.