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
Kosher animals upon the ground, and animals which dwell in water – not according to modern scientific classification). Most of the remaining animals on the list are either birds of prey or birds living on water, and the majority of the latter in the list also eat fish or other seafood. The Septuagint's version of the list comprehensively lists most of the birds of Canaan that fall into these categories. The conclusion of modern scholars is that, generally, ritually unclean birds were those clearly observed to eat other animals. Although it does regard all birds of prey as being forbidden, the Talmud