Felidae Oligocene, about 25 million years ago, with the appearance of "Proailurus" and "Pseudaelurus". The latter species complex was ancestral to two main lines of felids, the cats in the extant subfamilies and a third major group of extinct cats, which are assigned to the subfamily Machairodontinae. The machairodonts included the saber-toothed cats such as the "Smilodon". The "false sabre toothed cats", the Barbourofelidae and Nimravidae, are not true cats, but are closely related and together with Felidae and other cat-like carnivores (hyaenas, viverrids and mongooses) make up the feliform carnivores. Results of mitochondrial analysis indicates that all the Felidae descended
Felidae Conservation Fund field support, supplies and equipment to its project partners to help them achieve their research goals. To link this scientific research to conservation efforts, Felidae incorporates the results of field studies into its outreach and education programs. These include talks and presentations throughout the US, collaborations with artists and video producers to convey the conservation message through visual media, and online projects aimed at educating young people through an interactive portal, an online and mobile phone game, and social network activities. In its field work and conservation efforts FCF collaborates with the following organizations: National Park Service, California State Parks,