In a class of their own

I DON’T really know how to phrase this — I don’t want to annoy anybody or to end up sounding pedantic or silly. Not everybody realises that there is a time-honoured tradition in the newspaper business that one set of people write the articles and another set write the titles and headlines.

Last Monday I wrote an article about feral ferrets and it appeared under the title: “Ferreting out true numbers of feral rodents.”

Kind people have been phoning and emailing to tell me that a ferret is not a rodent. I actually know this. So, just to clarify things, let’s settle this business of how animals are classified.

An animal (or bird, or plant, or whatever) has two scientific names that are normally rooted in Latin, though sometimes a bit of Greek creeps in. A ferret is Mustela furo. The first name always starts with a capital letter and the second with a small letter and, in print, depending on the house style, the whole name is often in italic script.

The second name gives us the species of the animal. The first name gives us the genus, which helps us understand what other animals are its close relations. A mink is Mustela vison, so we instantly know that ferrets and mink are closely related.

The genus Mustela is contained within a family called the Mustelidae. If we look these up we can find other animals that are genetically related to ferrets, but not quite as closely as the mink or the stoat. These include otters, pine martens and badgers.

The whole thing is like a set of concentric circles. As you get further from the centre, the degree of kinship becomes less and less.

The next circle is the order to which the animal belongs. Our ferret belongs to the order carnivora which tells us that it is rather more distantly related to things like cats, foxes and bears.

The next circle is called a class and, in the case of our ferret, it is the mammals, or mammalia. The mammals are linked with birds, reptiles, amphibians and most fish to form the next classification, a phylum, in this case the chordata or vertebrates. Finally the vertebrates join up with other things like snails and worms to form a kingdom called the animalia.

There are four other kingdoms, monera or bacteria, protists, which are mostly single-celled creatures, plantae, or plants, and fungi, which are mushrooms and moulds. It’s really quite simple and every living thing has its pigeonhole somewhere in this seven-level classification system.

As far as mammals are concerned, there are members of eight orders living wild in Ireland. They are the insectivora — the hedgehog and the pygmy shrew; the chiroptera — nine or 10 species of bats; the lagomorpha, which are rabbits and hares; the rodentia, including mice, rats, squirrels and bank voles; cetacea, by far the largest because it contains the many species of whale, dolphin and porpoise found off our coasts; carnivora, which includes things like foxes, badgers, otters and stoats (and my ferret, of course); the pinnipedia are our two resident species of seal, plus the occasional vagrant walrus; and finally the artiodactyla, which are our three species of deer, plus feral goats.

It’s really not that complicated and though the system isn’t perfect, it does help to avoid confusion. In North America a red deer is called an elk but the same word is used in Scandinavia to describe what the Americans call a moose. In Ireland we sometimes use the word elk for an extinct giant deer that is not closely related to either of the other two. It’s hard to sort that kind of thing out without some kind of uniform international system.

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