Where do we find proves for evolution?

evolution
Photo: Eduard Olaru

I have purposely chosen this title. Those who are a bit familiar with biological sciences know that the proves for evolution are everywhere, the living matter has so many common features at all the species, plus the similarities at DNA level superpose the morphological and physiological ones between the species, that’s why we call them phylogenetically kindred. The proves for evolution are countless and everywhere for neutral persons, but not for those (let’s not call them creationists) who reject it from the start as a bad idea. They always say that no matter how many missing links were discovered, how many races of animals and species of plants were obtained artificially, they wouldn’t let themselves convinced about the existence of evolution until they see it in action, until they see species created in the laboratory.

What does a species mean? A species is a population in which there is an unlimited change of genes between its members, but it is isolated reproductively from other similar populations. This means that unless we have obtained from a mother-population another population which is isolated reproductively from the initial one, we don’t have evolution. Experiences in this regard weren’t satisfying; the artificial species of blowflies were later proven to be wild species, hardly detectable. However, it is often spoken about incipient species of plants.

Another important problem is the impossibility to obtain life in the laboratory, at least for now. If life cannot be obtained in the lab, its appearance being impossible from the unliving, then life didn’t appear from the unliving, as evolutionists suppose. We know the rest. I will try to answer these problems through my current knowledge.

Sex is the hardest to prove

What do those who deny evolution want, in order to be convinced of its existence? -Populations who isolated reproductively from the mother population. This is only about the species with sexed reproduction. Otherwise, there are artificial viruses, but viruses are entities at the limit between the living and the unliving. It is also considered that there are species at the bacteria, although they don’t have sexed reproduction. Still, they change genetic material (plasmids), and the species bacterium doesn’t exist in this case. Here starts the problem of resistance to antibiotics and of intra-hospital infections. Bacteria change plasmids which contain genes for resistance to antibiotics, both within the species and interspecies. This means that they give their genes to the resistance of kindred and of friends (it seems that the bacteria are not at all selfish, the selfish gene of Dawkins was not transmitted yet, the plasmid, because it didn’t appear).

Things are more complicated for the species with sexed reproduction. Sex or its absence (between populations) is very difficult to prove, Clinton knew best and showed it in the lawsuit related to the harassment of Monica Lewinsky. Very kindred and extremely similar species of trees, for example, are isolated reproductively because they have different periods of flowering. Also, at insects, very kindred species are reproductively isolated because they have slightly different nuptial dances, which make them not to recognize the possible partners. Reproductive isolation is sometimes related to some details which are less important from the biological point of view, but which have important consequences. This is in fact in the spirit of Darwinism, which says that evolution is made through small, slow changes.

These persons who deny evolution, when asked How do you explain the similarities between the species, if not through evolution? they will say that they come from the laws of living matter organization. According to them, human and chimp don’t have a common ancestor, although the similarities between these species are striking. In this case, there are data which show that there was subsequent hybridization between the initially separated branches which led to these species (Patterson et al., 2006; doi: 10.1038/nature04789).

An interesting question could be addressed to all those who deny evolution and don’t consider the similitude between the species, would be: How do they explain linguistic similarities between languages that are extremely far from the geographical viewpoint, spoken by people of different races (populations politically and genetically)? How do they explain the similarity between Turkish and Mongolian? And still, here we have historical documents of some migrations. Also, the similarity between today’s Dutch and the Hittite of 3000 years ago, spoken in Anatolia, today’s Turkey? Ceram, in The secret of Hittites really says that the scream of a thirsty Hittite, who asks for water, would be understood by a Dutch from the 20th century. We have proved that there existed connections between the ancestors of Hittites and Dutch? Here there are many missing links which we will probably never find, but without migrations, wars, trade, and of course sex, which is present at the contact between human populations, these similarities cannot be explained.

If you admit that languages have evolved one from another, that all the similarities of vocabulary and grammar are the natural consequence not of coincidence, not of a unique model of organization of languages (which would be, as Chomsky suggests, at basal level), but of the historical connections between human populations, then why don’t you admit that similarities in biology are the consequence of historical connections between species? Because you don’t like the idea. We all reject ideas that we don’t like, we all believe in extraordinary things, which don’t have anything to do with reality, like the free judge. But the difference is that some are in a greater extent conscious of that.

Let it be life in the laboratory

Another problem of those who deny evolution is the fact that for the moment the creation of life in the laboratory is not possible, that is the creation of living from the unliving. Experiments we all have learned in high school only show that important organic substances can be obtained in the chemistry of the living from the unliving, or that lipids have certain features that mime the existence of some microorganisms (the famous coacervates). But these experiments are very important for understanding of the living. Other working hypotheses, other experimental models, which will result from the theoretical understanding of the living, will probably lead sooner or later to obtaining life in the laboratory. If nothing was obtained until now, it doesn’t mean that it is not possible. Electricity has been unknown for thousands of years, and today it is obtained every day in the laboratory. What would those who deny evolution say then? If they are creationist probably they will horripilate that scientists pay God, like they did when cloning was a success, an incomparable one.

It is true; people don’t know much about evolution. If today we knew everything if Darwin’s theory were complete, then nobody would write scientific articles about evolution, books would no longer be written. Are books and articles about Newtonian mechanics written anymore? I wrote a book about human evolution, “Civilization of famine”. When I wrote this book I thought, in my credulousness, that it will convert many creationists into evolutionists or at least some will no longer deny evolution. A theory which explains why did the brain increase, why did fur disappeared, how did human thinking appear (which made possible the appearance of language), the typically human sexuality, plus the menopause etc., that the phenomenon they are based on is only one, ecological (documented in the history of species), which has documentary effects for those changes, could have offered less opportunities to attack. In science, the simplest answer is often considered the best, especially when it answers so many questions. After the book was published I asked such a person, about whom I knew he was a creationist, if he accepted evolution now that humanization can be reduced to an over activation of a metabolic way. The answer was no, because he didn’t see artificial speciation (appearance of new species in the laboratory).

Science should be separated from religion and philosophy, and people should separate science from religious, political and philosophical convictions. When I first read socio-biology, at university, I was very shocked at many theories and ideas. But if you want to reject scientific ideas, you have to do this with scientific means, if you cannot, you just have to accept them. I know how it is; socio-biology is very difficult to digest for a liberal.

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