Sunday, 23 February 2020

The Cat Family: Domestic and Wildcats

European wildcat
Perhaps surprisingly, there is some confusion and debate as to the correct scientific name for the familiar domestic moggy. There are, in fact, at least three different possibilities, all of which have their supporters among the people who study such things.

Firstly, there's the option that domestication has had such radical effects on the cat that it can be considered a separate species. In this case, its correct name is Felis catus. That name was first awarded to the animal in 1758, in the oldest listing of scientific animal names still considered valid. At the time, Carl Linnaeus, who wrote the list in question, intended it to apply to both wild and domestic forms, although the domestic version was raised to subspecies status by Johann Erxleben 22 years later.

That, unfortunately, led to further confusion, since it was his name - Felis domesticus - that ended up being picked when the wild and domestic forms were assigned to separate species. Under the modern rules for such things, however, the names of wild animals have priority over those of domesticated ones (at least for the seventeen most common domestic species for which this might otherwise be an issue). This means two things. Firstly, F. domesticus isn't a valid name any more, even though it is still used by at least some scientists in surprisingly recent sources.

Secondly, if the domestic cat isn't a distinct species, then the name first used to refer specifically to the wild animal is the one that counts. The problem here is that scientists can't agree on which species that is, either.

The latest version of the IUCN Red List, and many other reference works, list the wildcat (Felis silvestris) as the wild ancestor of the modern domestic cat. The disagreement comes because a number of scientists regard the wildcat as constituting two different species and, if so, it annoyingly happens to be the "other" one that the domestic animal was first bred from.

So, three possible names: F. catus (if it's a distinct species), F. lybica (if it's not a distinct species, but the African wildcat is), or F. silvestris (if all three forms belong to one species). Ho hum.

If the wildcat is, indeed, a single species, it's the most widespread of all the small cat species, being found through most of southern and central Europe, through Asia as far east as India and Mongolia, and through almost the whole of Africa, aside from the driest deserts and densest jungles. There's also an isolated population way to the north in Scotland. If it isn't, then there's a European species, which also lives in Turkey and the southern Caucasus, and a so-called "African" species (Felis lybica), which confusingly happens to include all the other Asian examples. (Wild cats in Sardinia are also assigned to the "African" species, rather than the European one, but this is probably because they are actually feral descendants of early domestic cats).

And, yes, before anyone asks, they can all interbreed, which doesn't actually prove anything, but probably explains why the "one wild species" model is the most popular.

In Europe, wildcats are found primarily in broadleaf forest, but in Asia and Africa they are willing to accept a wider range of habitat types. Even then, they mostly prefer shrubland or forest of various kinds, presumably because these provide sufficient undergrowth in which to hide and jump out on their prey. There are a few exceptions to these general rules, with some African wildcats living on open grasslands (which, if the grass is long enough, can still provide plenty of concealment), and Scottish wildcats being forced into more marginal heathland and hilly habitat due to the increasing decline of reasonable alternatives.

In the wild, cats are nocturnal predators, rarely venturing out in daylight hours, and often sheltering in natural crevices, loose brushwood, or burrows stolen from other animals. The bulk of their prey are mouse-like rodents which, depending on where in the world they live, may include such things as voles and gerbils, among others. It's probably no great shock to discover that rabbits and birds are also popular, with rabbits, for example, proving a particularly common prey item in both Spain and Scotland. In fact, if anything, wildcats are more likely to kill birds than domestic animals are, possibly because the lack of commercial cat food means that they're prepared to put in more effort to catch them.

Wildcats can breed at any time of the year, although there is a preference for certain seasons in parts of the world where the climate varies significantly throughout the year. In Europe, for instance, wildcats mostly breed between January and March, ensuring that the kittens are born in the spring. Initially raised in hollow trees, rocky crevices, burrows, or other shelter, kittens are able to kill at about two months of age.

African wildcat
Genetic analysis of wildcats across Eurasia and Africa makes it possible for us to narrow down the exact subspecies from which the domestic animal first evolved. This turns out to be the one that lives today in North Africa and the Middle East, with essentially no admixture from any of the other subspecies since. This makes perfect sense, since the first undoubted evidence we have of feline domestication comes from Ancient Egypt, where artwork shows the animals as far back as 1,600 BC, shortly before the dawn of the New Kingdom.

Of course, it doesn't follow that cats were not domesticated at all prior to this date, and it's perfectly possible that the first domestic cats appeared elsewhere in the Middle East, further back in the Bronze Age. In fact, it seems, that, unlike dogs, cats may have partially domesticated themselves. Whereas dogs were bred by humans from a very early point - certainly long before cats were - wildcats probably hung around human settlements, feeding off the mice and occasional scraps of food and slowly becoming more tolerant of human presence.

One difference between the wild and domestic animals is that the latter have a meow that is more pleasing to the human ear than that of their wild relatives. While dogs have a range of useful functions to humans, cats were probably not of much use unless they were killing mice out in the fields or granaries, and it's plausible that the more appealing members of their species were the ones that were later able to enveigle their way into our homes as well.

Those that did so eventually developed the genetic changes necessary for domestication of there own accord, while deliberate cat-breeding is a much more recent phenomenon, perhaps only dating from the Middle Ages. By this point, however, cats had already spread through the Old World alongside human agriculture, doubtless making themselves useful wherever mice were a problem.

Nowadays, domestic cats pose a danger to the continued existence of their wild cousins. Simply put, because they are more numerous and less threatened by habitat loss than wildcats, domestic cats tend to breed with them when the two live nearby, and it's the wildcats that lose out. This probably happens everywhere that wildcats live, but it's known to be a particular problem in Scotland, where the wild population has been almost driven to extinction, and also to be a major issue in Hungary and Portugal. Conversely, while it still happens, it's much less of a risk in South Africa, perhaps because of the lower human population density.

Chinese mountain cat
The closest living relative of the wildcat is the Chinese mountain cat (Felis bieti). In fact, it's so closely related that some scientists consider that it, too, is yet another subspecies of the regular wildcat - although, in its case, that doesn't seem to be the general consensus. Physically, it looks much the like wildcat, but is heavier, with a powerful build and shorter legs. It also has much fainter stripes than wildcats do (the natural colour of cats is tabby, with only a relatively small number of genes being responsible for all the variations we see in the modern domestic animal) and black tufts of hair on the tips of its ears.

Chinese mountain cats live only in central China, just east of the Tibetan Plateau in Sichuan, Qinghai, and (possibly) Gansu Provinces, over 2,500 metres (8,200 feet) above sea level. While undeniably high in altitude, this is more flat than mountainous, leading to the alternative name of "Chinese desert cat". Which, since it's not really a desert, either, may not be much help - the habitat is more accurately described as high, grassy, steppeland with occasional patches of forest.

But that would make for a rather lengthy name.

The remoteness of much of this area - especially those parts of it where the cats like to live - makes it difficult to study the animal, and very little is known of it. In most respects, it's probably very similar to the wildcat, with similar hunting, social, and breeding habits. Their preferred prey appears to be a mixture of voles, pikas, and zokors, but they also feed on ground-dwelling birds, such as partridges.

There are, however, some other very close relatives of the wildcat which we know rather more about, and which are almost universally regarded as separate species. It is to those that I will turn next...

[Photos by Alena Houšková, Stephen Temple, and "西宁野生动物园", from Wikimedia Commons.]

1 comment:

  1. "While dogs have a range of useful functions to humans, cats were probably not of much use unless they were killing mice out in the fields or granaries..."

    There are depictions in ancient Egyptian art of cats being used to hunt waterfowl, although it's not entirely clear whether they were actually used for that purpose, or whether the cats in the artwork were symbolic in some way.

    The Egyptians also considered cats as a form of protection from venomous creatures such as scorpions and snakes. It's possible however that the ancient Egyptians considered cats, civets and mongooses as basically the same type of animal.