 |
| Carl Nilsson Linnæus |
One of the scientists whom I've always regarded as remarkably lucky was
Carl Nilsson Linnæus (23 May 1707 – 10 January 1778), known later as Carl von Linné. Linnæus single-handedly devised the Linnean or
binomial nomenclature system of classification which is still used today, albeit slightly modified, to classify all living things and was rightly regarded as one of the greatest men of his time. He was probably also the first person to realise that human being were not only animals but apes and should be classified as such
He was born into a slightly eccentric Swedish Lutheran family in the village of Råshult in Småland and, from the outset, his parents spoke Latin to him so that, so it is said, he learned Latin before he could speak Swedish. He also developed an obsessive early interest in plants which he probably acquired from his father, himself an amateur botanist, and preferred looking at flowers to working at his education. The headmaster of his school, also a botanist, noticed his interest in plants and gave him the run of his garden, he also introduced him to the state doctor of Småland, Johann Rothman another botanist.
Rothman taught him about plant sexuality and introduced him to the
Tournefort system of plant classification, a system with many flaws based on almost arbitrary groupings, and clearly in need of revision and rationalisation. But is was the sexuality of plants which seems to have intrigued Linnæus the most, to the point where he became almost obsessed with sex, at least as the basis for classification.
His first thesis was
Praeludia Sponsaliorum Plantarum on plant sexuality. This choice as the basis for classification was a more or less arbitrary one in those times as there was no understanding of genetics or evolution, or the role of sexual reproduction as a selective factor in the evolution and divergence of species. In fact, when he came to classify the molluscs, finding no obvious genitalia, he based it on how closely the opening in the shell resembled the human female vulva, which he seems to have studied rather closely. In molluscs of course, that has absolutely nothing to do with reproduction.
So there were three stokes of luck here:
- Knowledge of Latin so he had a basis for nomenclature which had a pan-European understanding and which could be used descriptively as well as binomially to give a systematic naming convention.
- An interest in botany shared by some influential people.
- An obsessive interest in sex which had led him by chance to the most sensible basis for classification, given the intimate role played by sexual reproduction and diversification in most multicellular organisms (he did not know of single-celled organisms which had not then been discovered.
Perhaps the third in the above list needs to be explained a little more. For individuals to reproduce successfully, their genitalia need to match or else reproduction would be impossible. Hence the reproductive organs tend to vary only slightly between closely related species, more so between more distantly related species and more so still between even more distantly related species.
So, by doing what Linnæus did and classifying plants on the basis of their fundamental flower structure, such as the number of stamens and pistils, number of petals, form of the
inflorescence, etc, he had unwittingly linked his classification to the evolution of the species before there was a general awareness of evolution and before it was the accepted principle under-pinning the whole of biology that it is today.
Linnæus didn't always get it right - indeed how could he with no knowledge of evolution and genetics - but it is a tribute to his system that it gave the first clues to people like
Lamarck,
Wallace and
Darwin that there might be a reason why these varieties, subspecies and species, when arranged in orders, classes, phyla and kingdoms, looked like the branches of a tree. (Linnæus never included families; these were added later)
One of Linnæus' more subtle contributions to science was his insistence that not only should humans be classified as animals but that they should be included in a grouping which includes apes and monkeys.
Linnaeus classified humans among the primates (as they were later called) beginning with the first edition of Systema Naturae. During his time at Hartekamp, he had the opportunity to examine several monkeys and noted similarities between them and man. He pointed out both species basically have the same anatomy; except for speech, he found no other differences. Thus he placed man and monkeys under the same category, Anthropomorpha, meaning "manlike." This classification received criticism from other biologists such as Johan Gottschalk Wallerius, Jacob Theodor Klein and Johann Georg Gmelin on the ground that it is illogical to describe a human as 'like a man'. In a letter to Gmelin from 1747, Linnaeus replied:"It does not please [you] that I've placed Man among the Anthropomorpha, perhaps because of the term 'with human form', but man learns to know himself. Let's not quibble over words. It will be the same to me whatever name we apply. But I seek from you and from the whole world a generic difference between man and simian that [follows] from the principles of Natural History. I absolutely know of none. If only someone might tell me a single one! If I would have called man a simian or vice versa, I would have brought together all the theologians against me. Perhaps I ought to have by virtue of the law of the discipline".
The theological concerns were twofold: first, putting man at the same level as monkeys or apes would lower the spiritually higher position that man was assumed to have in the great chain of being, and second, because the Bible says man was created in the image of God (theomorphism), if monkeys/apes and humans were not distinctly and separately designed, that would mean monkeys and apes were created in the image of God as well. This was something many could not accept....
After such criticism, Linnaeus felt he needed to explain himself more clearly. The 10th edition of Systema Naturae introduced new terms, including Mammalia and Primates, the latter of which would replace Anthropomorpha as well as giving humans the full binomial Homo sapiens. The new classification received less criticism, but many natural historians still believed he had demoted humans from their former place to rule over nature, not be a part of it. Linnaeus believed that man biologically belongs to the animal kingdom and had to be included in it. In his book Dieta Naturalis, he said, "One should not vent one's wrath on animals, Theology decree that man has a soul and that the animals are mere 'aoutomata mechanica,' but I believe they would be better advised that animals have a soul and that the difference is of nobility."
Even in those days it seems die-hard theologians were insisting that science conform to their theology and were complaining when it didn't, and scientists were having to contend with their arrogant bullying and cat-calling from the side-lines.
Now, of course, we know that theology is wrong because it doesn't conform to what science tells us is right. Science, not theology, has proved a far superior tool for determining truth to the extent that it is now accepted by normal people as a tool for validating theology, or not, and not
vice versa.
You will even find fundamentalist creationists frantically trying to use science, albeit usually a bastardised parody version of it, to lend credence to their myths and superstitions, as science, paradoxically, closes more and more gaps into which they try to fit their diminishing little gods.
Partly in honour of his insistence on this classification for mankind, in 1959, Carl Linnaeus was designated as the
lectotype for Homo sapiens, which means that following the nomenclatural rules, Homo sapiens was validly defined as the animal species to which Carl Nilsson Linnaeus belonged.
It is more than a little ironic that, when Darwin and Wallace presented their seminal papers on evolution, which did so much to explain
why Linnean nomenclature works, to the
Linnean Society of London, it went almost unnoticed.
And yet, the theory is invaluable. I do not see how, without it, our knowledge could have grown as it has done since Darwin. In trying to explain experiments with bacteria which become adapted to, say, penicillin, it is quite clear that we are greatly helped by the theory of natural selection. Although it is metaphysical, it sheds much light upon very concrete and very practical researches. It allows us to study adaptation to a new environment (such as a penicillin-infested environment) in a rational way: it suggests the existence of a mechanism of adaptation, and it allows us even to study in detail the mechanism at work. And it is the only theory so far which does all that.2
