False killer whales have such a name owing to the shape of their skull, which resembles the skull of killer whales. However, the false killer whales are not deeply studied as killer whales and experts are yet to learn about them fully. Both these are mammals and belong to the dolphin family. 

Whales communicate via a variety of sounds. To be precise, according to experts, whales interact via a complicated range of noises, such as whistling, chirping, clicking, and so on. All these are collectively known as whale sounds.  Whales, however, lack a vocal cord and make sounds by squeezing air through the throat.