Natural History

African palm civets are not civets.

As regular readers of this blog know,  the order Carnivora is split into two suborders.

One of these is more widely covered on this blog for a very simple reason.  The suborder Caniformia gets more attention because that’s where dog and the dog family are located.  This suborder has much wider diversity in terms of ecological niches and varied species. There is a lot of difference between the tiny least weasel that weighs only between 1 and 3 ounces, and the Southern elephant seal, which can weigh 8,800 pounds.  All marine Carnivorans, seals, sea lions, and walruses, are Caniforms, as are all the animals in the weasel family (Mustelidae), which includes otters, badgers, wolverines, martens/fishers, polecats/ferrets, and mink. Skunks were initially thought to be Mustelids, but recent genetic studies have revealed that they belong to their own family called Mephitidae, which they share with two species of “stink badger” that are found in the Philippines and Indonesia.  The raccoon family (Procyonidae) is also Caniform and includes all both species of raccoon, the kinkajou, the olingos, the ring-tail and cacomistle,  and all the coatis. All bears, including the giant panda, are Caniform, and the red panda, once thought to be a bear or a Procyonid, is now classified in its own family called Ailuridae.

Now, classifying Caniformia hasn’t been nearly as difficult as classifying Feliformia.

That’s because the lineages and the physical traits of all of these animals really are quite distinct.

Feliformia has a bit of a problem.

The two best known Feliform families are cats (Felidae) and hyenas (Hyaenidae). It is usually a bit of a surprise for people to learn that hyenas are much more closely related to cats than they are to dogs.    The largest Feliforms are in these two families.

The rest of the suborder are smaller animals,  and what’s worse, many of these animals represent convergences and primitive lineages in such a way that they often resemble each other but aren’t closely related at all.

Mongooses and meerkats (family Herpestidae) are probably the best known of the little Feliforms. These are followed by the civets, genets,  African linsangs, and the binturong (family Viverridae).

And for decades, it was assumed that these all the things called civets or mongooses comprised these two families.

That’s because all these animals look superficially quite similar to each other. In Madagascar, there are animals that could be classified as mongooses or civets, and when classified as either, they were assigned to Viverridae or Herpestidae.

However, when we’ve started looking at the DNA, things have not been as clear cut as we might have assumed. All Malagasy carnivorans are closely related to each other, and they share a common ancestor with Herpestids. They are not closely related to Herpestids to be classified with them, but instead, they have been given their own family called Eupleridae.

But Madagascar is a island with lots of unusual species on it. Surely the mainland species are classified correctly.

Well, genetic studies have revealed that the Asiatic linsangs, the spottted and banded species, aren’t civets at all. They are actually very closely related to cats, and one could almost make the case that they belong in the Felidae family. They are currently classified in their own family called Prionodontidae. The African and Leighton’s linsangs of Africa very closely resemble the two Asiatic species, but they are actually civets. The four species resemble each other as the result of convergent evolution.

And then there is the African or two-spotted palm civet (Nandinia binotata).  Now, it is widely accepted that the modern civets are among the most primitive of all Carnivorans. But it has been suggested through morphological and molecular studies that the African palm civet is an even more primitive species than any of the civett which it superficially resembles.

It has thus been given its own family called Nandiniidae. Reginald Innes Pocock suggested that the African palm civet deserved its own family status in 1929. However, it spent some decades being classified with the Asian palm civet before finally being placed where Pocock believed it belonged.

Viverridae was a catch all family for many years. Anything that looked like a cat with a muzzle was placed there.

But because Feliformia retains many more ancient lineages than does Caniformia, things do get quite confusing.

In Caniformia, most of the smaller species are recently derived. For example, least weasels are derived from larger weasels. Within the genus Mustela, the long-tailed weasel represents the more primitive form. The ermine or stoat is the intermediate form, and the least weasel is the most derived form.

There are even two Caniform carnivorans that have evolved to look something like a civet.

In the Old West, they talked about keeping civet or miner’s cats to keep the mice down.

This so-called American civet is the ring-tail (Bassariscus astutus). It is found throughout the Western United States and in most of Mexico.  In southern Mexico and Central America, one can find the ring-tail’s closest relative, the cacomistle (B. sumichrasti).   These animals are both closely related to the two species of raccoons, but unlike them, this animal has essentially evolved into a civet-like forms.

It’s long been recognized that they are both Procyonids, but of course, the common terms for these animals suggest that they are civets or genets. Or even a type of cat.

One could make the case that the two Asiatic linsangs are actually very primitive cats, but one simply can’t say that a ring-tail or a cacomistle is anything like a cat.

They are raccoons that have become cats.

The only really bizarre taxonomic relationship in large carnivorans is that hyenas are more closely related to cats than they are to dogs.

But in the smaller and more primitive ones,  these relationships are much more bizarre.

And molecular analyses have not been performed on every species, so we may be in for some more surprises.

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And yes, I know that I’ve piqued your interest about the two Asiatic linsangs.

I’ll post something on them soon.