You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "What animal with only four extant species was the name borne by four ships of the Royal Navy?" whose answer is Hyena.
Each document should contain about 30 words, and these documents should contain useful information.

Query: animals with only four extant species
Useful Output:

Doc 1: Hyenas Of The World​​ Today, the Hyaenidae family includes only four extant species - the striped hyena (Hyaena hyaena), the spotted hyena (
Doc 2: Tuataras are pretty famously the only living species in their entire order.  Aardvarks are also the only surviving species in their order.
Doc 3: With only four extant species (each in their own genus), it is the fifth-smallest biological family in the Carnivora and one of the smallest in
Doc 4: These studies suggest hyenas are ecologically and socially diverse animals in the family Hyaenidae, with four living species that occupy various habitats
Doc 5: Hyenidae, a lineage that separated from viverrid ancestors 25–30 million years ago, comprises four extant species (Fig. 1): the aardwolf (Proteles cristatus),