Whales: Why are they classified as mammals?

Though some might find them scary, we can all agree that whales are extraordinary animals. They are just so different from other mammals, but are still considered one. Why so? Why are they not a part of the fish familia but instead considered a mammal? Let’s find out!

Obviously, whales are categorized as mammals since they have features that mammals have. Let’s talk about those features to better understand the situation.

Michaël CATANZARITI, CC BY-SA 3.0, via Wikimedia Commons

1) Whales breathe with their lungs

You may have thought that whales, just like every fish, breathes with their gills. That’s not true though! Whales do lung respiration, they have lungs just like every other mammal. You may have noticed that every once in a while they swim through the surface to get some oxygen, which indicates that they breathe oxygen, as well. Though unlike fish, they cannot breathe oxygen from the water, they need oxygen in air to breathe.

incidencematrix, CC BY 2.0, via Wikimedia Commons

2) Whales give birth

That’s right! Whales do not lay eggs like fish do. Though there might be some exceptions. Sharks, for instance, are fish but give birth. But sharks don’t have all the requirements to be a mammal, that’s why they’re considered as fish. Similarly, whales give birth to their children, but on the contrary they are not fish.

Gabriel Barathieu, CC BY-SA 2.0, via Wikimedia Commons

3) Whales have hair

Whales are known to have hair just like mammals though they shed their hair a few weeks after birth.

Mike Baird from Morro Bay, USA, CC BY 2.0, via Wikimedia Commons

4) Whales are warm-blooded

Unlike fish, whales are warm-blooded animals just like other mammals. They are endothermic homeotherms, which basically means that they balance their inner temperature with the help of the energy they convert from food. Whales have a thick layer of fat to protect them from cold temperatures. This also provides them heat as well as being a storage for food.

User:Lennert B, CC0, via Wikimedia Commons

5) Whales nurse their babies

As we can see from birds and fish, some animals do not nurse their children. They just lay eggs and let them go. But as we can see from animals who give birth, some animals have mother instincts and look after their children. Whales, just like every other mammal, give birth and thus nurse and nurture their offsprings.

S.E.Ingraham, CC BY-SA 3.0, via Wikimedia Commons

Bibliography:

https://naturalistecharters.com.au/blogs/why-are-whales-mammals/

https://saveourseas.com/worldofsharks/is-a-shark-a-fish-or-a-mammal