Most mammal babies live inside their mothers before they are born, just like humans.
How many things can you see in common between this human baby and this kitty baby?
When the baby is big enough, it comes out of its mother’s body. Many people mistakenly think that being born alive is something all mammals have in common. There are, however, a few mammals (like the duckbilled platypus) who lay eggs like a bird!
So what do mammal babies have in common?
Well, even though some baby mammals are born different ways, they all drink milk that comes from their mothers' bodies. Baby pigs, dolphins, bats and elephants all drink milk!
Because the babies rely on their mother's milk to live, the mammal mommies have to care for their young. The length of time varies from a few weeks for mice to many years for humans!
People have "baby teeth" or "milk teeth". So do all of the other mammals! The only exceptions are mammals like anteaters -- they don't have any teeth at all.
Mammal mothers are hard workers. Baby mammals learn from their mothers. Most of the mothers don’t really try to teach their babies, but the babies watch their mother and do the things they see her do. Through copying their mothers, baby mammals learn everything they need to survive.
So, what do mammals eat when they grow up? They eat all sorts of different things! Lions are mammals who eat meat – they are called carnivores. Cows are mammals who eat plants – they are called herbivores. People are mammals who eat meat and plants – they are called omnivores.