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
The Lives of Animals contribution would more properly be called a scholarly article and Smuts' article, while grounded in her scientific studies, is mostly autobiographical and anecdotal. The Lives of Animals The Lives of Animals (1999) is a metafictional novella about animal rights by the South African novelist J. M. Coetzee, recipient of the 2003 Nobel Prize in Literature. The work is introduced by Amy Gutmann and followed by a collection of responses by Marjorie Garber, Peter Singer, Wendy Doniger and Barbara Smuts. It was published by Princeton University Press as part of its Human Values series. "The Lives of Animals" consists of two