naar Nederlandse versie
DOUBLE SCIENTIFIC NAMES AND TAXONOMY.
On the previous page we learned about the advantages of the (double) Latin/Greek names of species, now we'll have a look at the function of these names for the classification of the species.
For centuries, mankind felt a strong need to control and order the surrounding world. The overwhelming and uncontrollable nature that he lived in, should at least be named orderly. But such order is also indispensable for a better understanding of nature. So there were many scientists that engaged in this ordening and nomenclature, among them Aristotle.
The word taxonomy (taxo - make order, nomie - name) is often used for that classification, it is not exactly the same, but just for now let's pretend it is. You may think of a taxon as a larger or smaller box for the grouping of the species. The Swedish professor Carl Linnaeus introduced a ingenious system for the classification of nature, a system that we still use today. He adopted the binomial nomenclature ('double names') of Gaspard Bauhin, who used the 'two term naming' already in 1623 in one of his books on plants. Linnaeus used this system even stricter and not only on plants, but also on animals. With his system, Linnaeus thought he did justice to a divine influence and nature soon would be fully classified. But on to this day, only 10 percent of all living things have a name. More on Linnaeus at the end of this page.
You could see this as a box system, or more contemporary, a file system with folders on your laptop. Suppose we create a folder called genus1. To all species, belonging to that genus we give a double name, consisting of the Genus1 name and a unique name, like: 'Genus1 species1', 'Genus1 species2', etc. Then we store these double names in the Genus1 folder. Let's then create a folder called Genus2 for other species, that have characteristics like those of Genus1, but not enough match to put them in the Genus1 folder. Now to create a folder called Family1, and put both folders Genus1 and Genus2 in it. And thus we continue, untill we have a system with folders that contain folders that contain folders that contain... and so on. In classification, such a folder is called a taxon. The highest taxons in the system of Linnaeus were the kingdoms. These kingdoms were divided in tribes, the tribes in classes, the classes in orders, the orders in families, the families in genera and the genera in species. Those last two taxons determine the name of the plant or animal. The taxons, which are the folders of our previous example, have been adjusted many times. But more than that, in present time the taxons are seen as nodes and branches of phylogenetic trees, that are still developing. With that fundamental change, classification came closer to the true nature of nature...
In 1996 a new classification of Carl Woese was accepted, which has six kingdoms. With this classification a new taxon was introduced, above the kingdom: the domain. There are three domains: 1 the bacteria, with the kingdom Bacteria or Eubacteria, 2 the archaea with the kingdom Prokaryota and third the Eukaryota with the kingdoms Protista, Fungi, Plantae en Animalia. You can read more in this article on Wikipedia.
Now let's put side by side four animals:
| Taxon | HUMAN | CAT | BLACKBIRD | HONEY BEE |
|---|---|---|---|---|
| Domain | Eukaryota | Eukaryota | Eukaryota | Eukaryota |
| Kingdom | animals | animals | animals | animals |
| Tribe | vertebrates | vertebrates | vertebrates | arthropods |
| Class | mammals | mammals | birds | insects |
| Order | Primates | Carnivores | Birds | Hymenoptera |
| Family | humanoids (Hominidae) | cats (Felidae) | thrushes | bees (Apidae) |
| Genus | Homo (human) | Felix (cat) | Turdus ('real' thrushes) | Apis (bee) |
| Species | sapiens (the knowing) | domesticus (of the house) | merula (blackbird) | mellifera (honey making) |
This table suggests the cat being closer to us, of course it's a mammal too. The blackbird is not, but it still is a vertebrate. The honey bee is further away from us, its only similarity being an animal. That seems alright, but in a way not very satisfying: the bee has a head and legs, unlike a worm, which would drop out at the same spot in the table. The present phylogeny often gives a clearer view on the relationships.
CARL LINNAEUS
was the son of a Swedish doctor. He came to the Netherlands for a study in the city of
Leiden. In those days plants still were an important source for medicines and Linnaeus had a
passion for plants. In 1749 he wrote a book on medicinal plants, the Materia Medica.
But he had already published his most important work before that: the Systema Naturae
of 1735 ! In that first edition, (just a few folio sheets) he divided nature in three
kingdoms: animals, plants and minerals. That last kingdom may seem strange, but is
understandable from his perspective as a physician: medicines could originate from all three
kingdoms.
At present time we know six kingdoms in taxonomy, as written above. All those changes would
have surprised Linnaeus, who believed that all species were fixed and unchangeable. Darwins
work certainly would have shocked him, especially the thought that no Almighty
Creator was involved. But even in our 'enlightened age' that's still
unacceptable for many humans...
ABOUT THE FIRST EDITION OF 'SYSTEMA NATURAE'
In the first publication, Linnaeus divided the REGNUM ANIMALE (animal
kingdom) in five tribes:
Linnaeus and one sleepy guy (National Geographic)
Het Nederlandse Soortenregister (Dutch register of species), offers a tree structure
