Whales are mammals, just like you and I – and your cat and your elephant (if you happen to have a cat and an elephant).
Whales have fur
Like all mammals, whales have fur, though it is very thin (sort of like my dad’s hair, hehe).
Whales have lungs
Take a deep breath… now hold it. Wait! Keep holding it…
Like all mammals, whales have lungs. Having lungs means you have to breathe air.
Phew! You can let go and take another breath now. Breathe some air just like a whale!
Holding your breath can be pretty hard but whales have to do it all the time. Sperm whales can hold their breath the longest at 90 minutes, but most types of whales hold theirs for about 20 minutes. If a whale gets trapped under water in a fishing net or under the arctic ice, it can drown.
By the way, the world record for the longest a human has held his breath (at the time of this writing) was by a Brazilian named Ricardo Bahia who held his for an amazing 22 minutes. He’s as good as most whales!
Whales are endothermic
Well that’s a big word.
Endothermic is a fancy word that means, “can regulate temperature”. Another way we say this is that whales, like all mammals, are warm-blooded animals.
Mammals’ bodies use the energy they gain from eating food to heat the blood. They also have a thick layer of fat, called blubber, close to the surface of their skin to keep them from losing heat. This is especially important for marine mammals like whales as the water takes heat from an animal more than air does (think of how quickly you get cold in a chilly swimming pool). Even with all their blubber, whales have to burn a lot of energy to stay warm.
Whale calves drink milk
Another thing that all mammals have in common is that the mothers produce milk to feed their babies. The milk gives the calves much needed energy (which they use to stay warm, remember) and it also allows the mother to pass on immunities to some diseases.
Because the calves need their mother’s milk, whale babies stay with their moms for a year or two (depending on the type of whale). During this time, the babies are protected by their mothers, learn habits from their mothers and drink a lot of milk to build up their layer of blubber -- gray whales, for example, drink 50,000 gallons of milk each day! The container of milk in your fridge is likely in a gallon container – yikes, 50,000 gallons is a lot!!)