<human>:  In the new Planet Earth II Documentary film, how many species of animals are there on Earth?
<bot>: The number of species on Earth is estimated to be between 5 and 30 million. This is a difficult question to answer without more information. The number of species depends on how you define a species. For example, a species may be defined as a group of organisms that can interbreed, or a group of organisms that are capable of producing fertile offspring.