Why I Am a Christian

Saturday, 26 September 2015

Understanding Those Strange Scientific Names

     Once, when I was studying for my M.Sc., Lone Pine Sanctuary was suddenly invaded by a host of girls from some private school, obviously as part of a science project, for they each carried a list of questions to be researched. To the question, "What is the scientific name of the spiny anteater", half of them had nothing, and the other half had written "echidna", which I suspect is what the nuns expected. In any case, I always religiously crossed it out when they showed it to me, and wrote, Tachyglossus aculeatus, tried to teach them how to pronounce it, and informed them that I was a zoologist, and knew what I was talking about.
     All this raises a subject which is probably arcane to most of you. What is the purpose of these strange scientific names? Who coins them? What is wrong with "echidna", or even "spiny anteater"? Indeed, how do you pronounce the silly things anyway?

     I shall deal with the last question first, because Anglophones (speakers of English) tend to suffer from macroxenolexiphobia, or the fear of long foreign words. I even knew someone who read the whole of The Lord of the Rings without bothering to pronounce the proper names. Typically, they get a mental block when they see words in italics. So here is a test for macroxenolexiphobia. When you see the word, Tachyglossus do your eyes glaze over and your mind freeze up? Do you say, "It's all Greek to me"? If so, you are right; it's a pure Greek word. Here's another: "chrysanthemum". And another: "hippopotamus". Objectively, what's hardest to pronounce? Obviously the last two. However, we don't have any problem with them because they have been naturalised, and we think of them as English words.
     If you are a baby boomer like me, it should not be difficult, because you were taught to read by the phonics method. So, when you see a zoological name, take a deep breath, and divide it up into syllables: Tachy-GLOSS-us. See! That wasn't difficult. Now let's try the Latin word which follows it: a-cu-le-A-tus. Simple!
     Any pronouncable combination of the 26 Latin letters is permissible. However, because the names are theoretically Latin or Greek, we must observe the conventions of those languages. An -e at the end of a word is not silent, but pronounced. Also, unless the word obviously derives from a proper name, a ch is pronounced "k". Thus, in 1904, an entomologist called Kirkaldy named a genus of bugs Ochisme. It looks Greek, but is actually pronounced, "Oh, kiss me". He then went on to create a whole string of bug names ending in -chisme, and commencing with words which resemble women's names. Likewise, Eubetia bigaulae (a moth) is pronounced, "You betcha, by golly!" No-one can complain that taxonomists (the people who do the classifying) have no sense of humour, and if you wish to tickle your fancy with a few other examples, you should try this website.

       I shall save till later the explanation of what is wrong with "echindna". As for "spiny anteater", well, you might know what it is. But what do you call a "blue bottle"? Is it a large blowfly, or a jellyfish-like creature? There is a certain fish off the coast of North America which has been variously known as the angler, monkfish, goosefish, frogfish, fishing frog, toadfish, pocketfish, nassfish, all mouth, she devil, devilfish, widegut, widegap, and kettlemore; it is easier just to settle for Lophius piscatorius. And what about foreign languages? It took me a long time reading papers in French before I realised that  a "ouistiti" was what we would call a marmoset. And what about all the thousands - nay, hundreds of thousands - of creepy-crawlies and single celled organisms which have no popular name?
     It is clear that we need a single naming system which cuts across languages and districts, and is accepted universally.

Binomial Nomenclature
     This is where the eminent Swedish naturalist, Carl Linnaeus (1707-1778) came in, for he popularised the use of "binomial nomenclature", which simply means a naming system using two names. Like us, every species possesses both a personal name and a surname but, as with the Chinese and the Hungarians, the surname comes first. The double name is typically written in a different font from the main text, usually italics. The first name is always capitalised, the second is always in lower case, even when it is based on a proper name. (Journalists often make mistakes about this.) And because Latin was the language of scholarship at the time, theoretically the names are in Latin.
     The second name refers to the species, which is Latin for "appearance", while the first refers to the genus ( plural, genera), which is Latin for "kind" or "sort", which is a collection of closely related, and similar, species. Thus, the Latin word for "dog", Canis gives us the generic name of all doglike mammals. Hence:
     Canis familiaris (familiar dog) - the domestic dog;
     Canis lupus (wolf dog) - the wolf;
     Canis latrans (robbing dog) - the coyote;
     Canis aureus (golden dog) - the golden jackal; among others.
     Normally, once the genus has been established in the text, the initial alone is used eg C. lupus.

The Joy of Latin
    I don't know how zoologists get on creating names if they haven't learned Latin. It possesses many endings depending on gender, number, and case. Proper names are usually Latinised before being introduced into a scientific name. For example, Banksia is named after Sir Joseph Banks. These days, Greek roots are used as frequently as Latin ones, and since the two languages are related, Greek endings are usually replaced with Latin ones. Thus, the Greek word for "lizard", sauros produces all those famous dinosaur names ending in -saurus. As a general rule, the transformation is as follows:
     Masculine -os becomes -us;
     Neuter -on becomes -um; and
     Feminine -e changes to -a or remains the same.
     The specific name can be another noun eg lupus. Alternatively, it can be an adjective, in which case it must agree in gender with the generic name. I have already listed the three most common gender endings. There is also another set of nouns such as Canis, ending in either -is or -s, whose gender must be learned, because they can be either masculine or feminine. The corresponding adjectives end in either -is or -s for masculine or feminine, and -e for neuter. Confused?
     Finally, the specific name can be a noun in the genitive of possessive case. Thus, the common silver gull of eastern Australia is called Larus novaehollandiae or "the gull of New Holland". The second name (note that it is not capitalised) is the genitive of nova hollandia, a Latinised version of "New Holland". A little marsupial mouse called Antechinus stuartii was named after a Mr. Stuart, whose name is Latinised as stuartius, the genitive of which is stuartii. The rule for forming the genitive is:
      Masculine -us becomes -i;
      Neuter -um also becomes -i;,
      Feminine -a becomes -ae;
      Common -s or -is becomes (or stays) -is.

How Is the Naming Done?
     Before we go into details, it will be useful to explain the difference between a species and a genus. Generally speaking, a species refers to a population of individuals which are capable of interbreeding. At the same time, different species cannot, or at least normally do not, interbreed. (This definition is not, of course, terribly popular with students of fossil animals, or of those which reproduce asexually.) A genus is a group of closely related species. How closely related is a bone of contention between the "lumpers" and the "splitters". The lumpers use the classification system to emphasize similarity; they tend to "lump" as many species as possible into the same genus. On the other hand, the splitters use it in order to emphasize differences; they are more likely to split the same set of species into two or more genera. Both approaches are legitimate. It is like the human concept of "family". Does it mean your nuclear family alone, or your extended family? It can mean either - provided we are consistent ie if we include our cousins on one side of the family, we must include the other side.
     If a zoologist wishes to create a new species name, he must describe the species in enough detail to allow it to be recognized, and nominate a specimen, usually in a museum, as the "type specimen" so that any later investigator can refer back to it. Any other specimen belonging to the same species must have the same characteristics as the type specimen.
     If he creates a new generic name, then he must stipulate a particular species as the "type species". The importance of this becomes clear if it ever appears that some species is so different from the other members of the genus that it really belongs to a separate genus. In such a case, the type species retains the generic name, and it is the other species which moves. For example, Homo sapiens ("wise human"), the name for our own species, is the type species for Homo. In the nineteenth century a new subhuman fossil was discovered in Java and given the name, Pithecanthropus erectus ("erect ape-man"). Since then, a lot of subhumans have been discovered, and the similarities between Java Man and modern man appear more cogent than the differences, so it is now classed as Homo erectus. But, if at any time, it is decided that the two species are so different than they really belong in separate genera, it will be erectus which will be kicked out of Homo, not sapiens,
     At this point it might be useful to say a few words about subspecies, or races. When a species is divided up into subspecies, then the type specimen of the species becomes the type specimen of the subspecies with the same name as the species. Confused? A simple example will clarify it. The echidna, Tachyglossus aculeatus currently consists of five recognized subspecies. Because the species was originally described from New South Wales, the subspecies of the coastal and Dividing Range slopes of the southeastern states is called Tachyglossus aculeatus aculeatus. That of Kangaroo Island is T. aculeatus multiaculeatus, while the Tasmanian subspecies is Tachyglossus aculeatus setosus (which means "bristly" because, due to the colder climate, it has more hair among the spines). If the Tasmanian race were subsequently found to be so different as to be a separate species, it would be called T. setosus. On the other hand, if the New South Wales race were to be found to be a different species, then it would keep the name aculeatus, and all the rest would default to whichever name was given to the second subspecies described.
     A recent example of this process occurred with respect to the African elephant, Loxodonta africana. It used to be divided into two subspecies: the savanna elephant, L. a. africana and the forest elephant, L. a. cyclotis. Then, in 2010, DNA analysis revealed that they were divergent enough to be considered separate species. (How could we overlook an entire species of elephant? one expert asked.) So now the forest elephant has been elevated to a species in its own right, L. cyclotis. But don't assume that any of this is set in concrete, because new information on the relationships between animals is constantly coming in. For example, you will note that I recorded the domestic dog and the wolf as separate species. That was how it was when I began my studies. Nowadays, the tendency is to treat the dog as merely a subspecies of the wolf. However, the most recent research suggests that the original classification may have been correct after all.

The Rule of Priority
     To establish some sort of order in the chaos, two rules apply. The first is that every species and every genus can have only one name. Note that there are separate lists for zoology and botany; it is theoretically possible for the same name to be shared by both an animal and a plant.
     Please also note that, whereas the generic name consists of only a single word, it is the double barreled name which is the name of the species. Because the specific name is supposed to be a qualifier of the generic name, it is quite common for the same specific name to be attached to different genera, thus:
     Larus novaehollandiae, the silver gull;
     Dromaius novaehollandiae, the emu;
     Pseudomys novaehollandiae, the New Holland mouse.
     None of these names will need to be changed unless it is decided that two of the species ought to belong to the same genus. This must be considered extremely unlikely.
     The second rule is that the name first described always has priority. Now you can see what went wrong with the spiny anteater. It was originally christened Echidna, meaning "viper", in reference to its tongue, but that name was already in use for a genus of eels. The same thing happened to the platypus. Originally called Platypus anatinus, its generic name was pre-empted by a genus of insects. It was then re-christened Ornithorhynchus paradoxus. Wrong! The generic name had been pre-empted, but not the specific name. The correct name is Ornithorhynchus anatinus.
     These days you can consult a large directory listing all the scientific names ever in use. But there are other ways in which a genus or species can end up with a collection of invalid synonyms. Just as two subspecies may turn out to be separate species, so what were regarded as separate species may turn out to be merely subspecies. (After all, a visitor from outer space might assume that Europeans, Chinese, and Africans were three different species.) In such a case, the earliest named species has priority. Also, a scientist - especially one of the "splitter" mentality - may have underestimated the natural variation in a population. It would be like assuming blonds, brunettes, and redheads were all different species. There have been occasions when males and females, or even juveniles and adults have been given separate names.
     Back in 1879, the famous palaeontologist, O. C. Marsh coined the name, Brontosaurus for what was then the most complete sauropod specimen known, and it became a famous museum display. The trouble was, he had already described a smaller dinosaur, Apatosaurus just two years earlier. Then, in 1903 another scientist, Elmer Riggs realized that, although the description of Apatosaurus was meagre (just two paragraphs), it was enough to reveal that it was simply a juvenile Brontosaurus. Unfortunately, the genie was already out of the bottle. Children's books, movies, and popular articles were busy copying one another and citing the name, Brontosaurus, even though scientists had already given it up. Just the same, after a hundred years, it looks like Brontosaurus really was different from Apatosaurus after all, and the name may be due for a comeback.
     Finally, species are constantly changing genus the way film stars change spouses. Better knowledge of the relationship between species is one reason. The other is the eternal war between the "splitters" and the "lumpers". Marsh, needless to say, was a splitter.

Where Do You Publish?
     Essentially, anywhere. Preference should be given to peer reviewed journals with a widespread readership. When everybody has been using the same name for ages in multiple publications, it can be quite frustrating to discover that the species or genus had been previously described in some obscure journal, and the older name now has priority. But there are no rules as to which publications are valid.
     In 1999 a dinosaur museum in Utah purchased a fossil smuggled out of China which appeared to be a link between the dinosaurs and birds. The National Geographic got wind of it, and it was agreed that a paper on the fossil, to be named Archaeoraptor lianoningensis, would be submitted to the prestigious journal, Nature, while National Geographic would include a reference to it in an article on feathered dinosaurs, of which many have been discovered. However, once the scientists had a closer look at it, it became obvious that the fossil was a fake; the tail of one fossil had been glued to the body of another. The paper in Nature never eventuated. Unfortunately, National Geographic had unwittingly gone ahead with their article, so now they were left holding the baby as the official publication. The name can now never to applied to any other species or genus.
     Why, you might ask, can't it be re-used, since we know that the animal to which it had been attached was bogus? Well, there is still the possibility that further research will establish that it was genuine. Besides, there are many other cases where the situation is not so clear cut. The system is complicated enough as it is without adding any extra source of confusion.

Constant Change
     By now you may have come to the conclusion that the system is a tad confusing. It is. Any good review of a species always includes a list of recent synonyms so that researchers can find their way around older publications - which are often quite important. I've discovered that an awful lot of the names of prehistoric animals I knew and grew up with as a boy are obsolete. But it is the best system we've got. Remember: most of the creepy-crawlies of the world have no common name in any language.
     Just the same, one sometimes wishes things would stand still for a while. For example, the kangaroos and most of the big wallabies belong to the genus, Macropus, which means "long foot". Thus, the eastern grey kangaroo is M. giganteus (the type species), the western grey is M. fuliginosus, and the euro or wallaroo is M. robustus. The one exception, at the time I went to university, was the red kangaroo, whose genus was Megaleia, meaning "magnificent". But then it was decided that there was no good reason for assigning it to a separate genus. So Megaleia rufa became Macropus rufus. (Note how the specific name changed to match the gender of its new genus.) However, now it has been decided that the red kangaroo and euro are different from other kangaroos, and deserve a genus of their own. But it can't revert back to Megaleia, because an even older generic name exists for the euro: Osphranter. I have noticed, however, that a compromise has been made. Osphranter has now been treated as a subgenus, and written in parenthesis ie Macropus (Osphranter) rufus. (Note that the type species is also the type for the subgenus, which has the same name as the genus.)
     Back in the 1970s Vincent Serventy came to the Australian Mammal Society and made a proposal - subsequently accepted - that a committee should be formed to invent "common names" for all those marsupial mice, rodents, and bats about which the layman knew next to nothing. He made the point that if you were to go to John Gould's mid-19th century classic, The Birds of Australia and look up the scientific name, you probably wouldn't find it. If you looked up the common name you probably would.