There's no way to speak for all animals, but there is evidence that some animals do have ways to differentiate each other. Some parrots, for example, seem to identify themselves with specific sets of peeps, and it's possible their parents give them those names. Sweet, right?

And parrots aren't the only animals we suspect name each other. Dolphins also have distinctive whistles that function similarly to names. To prove this, researchers played a variety of whistles to a group of dolphins, and the individuals only replied to their signature sound, as if they were calling back when their name had been called.