Monday, July 15, 2013

The Evolution of Cats

While I am not fond of domestic cats, I must express my admiration for the hunting prowess of those strict carnivores.  Today, 37 species of felids inhabit our planet, all of which originated from a common ancestor that lived in Asia during the late Oligocene, some 25 million years ago.

DNA studies indicate that at least 8 felid lineages have evolved since that time and that cat species have been native to all Continents except Australia and Antarctica.  Migration of species between the Americas, Eurasia and Africa has been occurring for at least 12 million years (during periods when low sea levels opened the Bering land bridge) and genetic evidence suggests that the migrations have occurred in both directions.  For example, the cheetah, now limited to Africa, actually arose from a North American lineage and is more closely related to cougars than to the lions, tigers and leopards of Asia and Africa.  Some felid lineages, including one that gave rise to the saber-toothed cats, are now extinct .  Those lineages that still exist are grouped within two sub-families: the Pantherinae (including lions, tigers, leopards and jaguars) and the Felinae (including cougars, cheetahs, lynx, bobcats, ocelots and the domestic cat, among others).

Current archaeologic evidence suggests that cats were first domesticated in Egypt, about 4000 years ago.  While most of their wild cousins are endangered by habitat destruction, hunting, poaching and other human-related factors, domestic cats (many of which are feral) thrive in towns and cities across the globe; their numbers far exceed the population of all other cat species combined.