... issue of 'Scientific American' [www.SciAm.com]*. It shows how genomic DNA analyses have augmented more traditional investigative methods to unravel the mysteries of lineage of the nearly 40 surviving species of cats (felidae) in eight lineages in the world - ranging from the "great roaring cats" to small wild cats of all kinds to our beloved domestic cats (if they ever have been domesticated).

The article also traces the complex migrations of cat species around the world - apparently strongly driven by major cyclical fluctuations in sea level over the 10+ million years that the felidae have been in recognizable existence. It's reportedly only over the last 10,000 years that domestic cats have consorted with humans (presumably since we developed settled habitats and agriculture in the Neolithic).

The authors present some interesting statistics - there are estimated to be some 600 million domestic cats in the present world (which is about one cat for every 10 people on the planet). But it is feared that, despite their evolutionary success in spreading to all the continents and climatic regions of the earth, all the wild cat species may be doomed to eventual extinction - largely because of adverse human activity and loss of the cats' natural habitat.

[* O'Brien, SJ & Johnson, WE, The Evolution of Cats, Sci Am, 297(1), 68-75, July 2007.]

I'm convinced that house cats (like our Hank) exhibit unique behaviors not found in the usual domestic cat that is allowed to roam the streets. We often comment that, "Hank doesn't know how to be a cat" and figure that since he hasn't been near another cat since he was a very young kitten he didn't learn "cat stuff".

... established over millions of years of evolution that are fascinatingly common to all species within the feline order - the way they establish territory, show affection, and communicate, for example - but that those patterns are overlain or added to in species or individuals that interact with humans, regardless of the extent of tameness or domestication.

Our 18-year-old indoor cat, Missy, for example, has many routines that relate to our household routines and activities; appears to understand (or at least react predictably and purposefully to) a range of spoken words; and is very vocal in a way that is not shared by the outside cats in the TNR'd feral colony that we care for. Some of the ferals, however, do come to us, even jumping briefly onto our laps, for affection as well as food; but they are rarely vocal and do not appear to speak to one another.

Back in my zoo-keeping days I had some opportunity to interact - very carefully and under the curator's or a vet's supervision! - with large cats (tigers and a leopard); and was fascinated by how some of those cats' behaviors (showing affection, and vocalization, for example) resembled those of domestic cats. I learned years later from a bioacoustical scientist who had studied them that tigers utter a similar range of vocal greeting and other sounds to that of domestic cats (maybe 20 or 30 distinct sounds) - except that big cats can roar but apparently can't or don't purr.

The particulalrly interesting thing reported to the Acoustical Society of America was that a majority of the sounds that are made by tigers that have been raised by or lived in some kind of relationship with humans are uttered only to (or in the presence of) people; and almost never to other tigers. The same is likely true of domestic cats' utterances: other than communications between mother cats and kittens, it seems that domestic cats mew to us a lot but rarely to other cats.

Possibly all these animals are trying to emulate or participate in human communication. The same may be true of barking in dogs. It appears that all of the non-domestic dog species (including wolves, coyotes, dingos and the like) share our pet dog breeds' vocal apparatus for barking but very seldom do bark in the wild.