XXVII.2.5 The consistency of phylogenetic trees obtained from a sequence of different genes and their consistency with trees obtained on the basis of classical traits also confirm the evolutionary theory of the origin of species

Molecular biology has provided a great deal of evidence for the evolutionary theory of the origin of species.When we obtain sequences of a section of a certain gene from the members of several taxa, the difference between the sequences of these genes allows us to establish the probable order of branching off of the relevant taxa from the common ancestor.This is, in itself, still not evidence for the existence of biological evolution.The fact that the particular species branched off from a common ancestor in a certain order was already included amongst the assumptions forming the basis for the relevant method for construction of the phylogenetic tree.For example, if we were to take a collection of stamps, one from each country of Europe, measured all the possible characteristics of their patterns and words and were to feed these characteristics into a suitable computer program for molecular taxonomy, it would provide us with a phylogenetic tree without any hesitations, and this would show the order in which these stamps apparently branched off from a common ancestor.(I am exaggerating a bit; a good molecular-taxonomic program would also allow us to determine that our data set does not contain sufficient phylogenetically significant information and thus that the topology of the tree is not very credible.) However, evidence for the evolutionary theory could be obtained if we were to subsequently scan several other genes from the particular species and create a separate phylogenetic tree for each of these genes and were to discover that all the obtained trees would be identical, at least in their general characteristics.In addition, this topography would most probably be identical with the topography of the tree obtained on the basis of classical, for example morphological traits.In contrast, if we were to take our collection of stamps and measure first the chemical composition of the glue, secondly, for example, the structure of the paper, thirdly the distribution of colors in the pattern, etc. and again were to feed the obtained datasets into a computer, the resultant phylogenetic trees formed on the basis of the various sets of traits would most probably differ fundamentallyThis result is quite difficult to explain in any other way than that the particular organisms, in contrast to the stamps, were formed in a certain sequence, one from another.Of course, this still does not demonstrate that they were formed during a long period of natural evolution; however, it does exclude all theories based on the independent, natural or supernatural origin of the species.

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The classical Darwinian theory of evolution can explain the evolution of adaptive traits only in asexual organisms. The frozen plasticity theory is much more general: It can also explain the origin and evolution of adaptive traits in both asexual and sexual organisms Read more
Draft translation from: Evoluční biologie, 2. vydání (Evolutionary biology, 2nd edition), J. Flegr, Academia Prague 2009. The translation was not done by biologist, therefore any suggestion concerning proper scientific terminology and language usage are highly welcomed. You can send your comments to flegratcesnet [dot] cz. Thank you.