There are plenty more answers needed if the full-blown concept of undirected Darwinian evolution (accounting for not only variation but speciation) is ever going to be accepted as fact – even though a lot of people think that day has already come. Some time ago I noted down from a radio interview a very honest and helpful list of questions that there are still no answers to, provided by Dr Anjali Goswami, UCL and Prof Scott Armbruster, Portsmouth University.
- What actually drives morphological variation?
- How do we get the variety of forms that we see today?
- Why do we see those and not other forms?
- How does natural selection operate in the wild?
- How does speciation occur?
- What created the patterns and diversity we see today?
You might add to this the extremely difficult issue of DNA. Karl Popper writes (‘Scientific Reduction and the Essential Incompleteness of all Science,’ in Ayala, FJ and Dobzhansky, T (Eds.), Studies in the Philosophy of Biology (London: MacMillan, 1974), 270):
What makes the origin of life and of the genetic code a disturbing riddle is this: the genetic code is without any biological function unless it is translated; that is, unless it leads to the synthesis of the proteins whose structure is laid down by the code. But, as Monod points out, the machinery by which the cell (at least the non-primitive cell, which is the only one we know) translates the code ‘consists of at least fifty macromolecular components which are themselves coded in the DNA’ [citing Monod]. Thus the code cannot be translated except by using certain products of its translation. This constitutes a baffling circle; a really vicious circle, it seems, for any attempt to form a model, or a theory, of the genesis of the genetic code. Thus we may be faced with the possibility that the origin of life (like the origin of the universe) becomes an impenetrable barrier to science, and a residue to all attempts to reduce biology to chemistry and physics.
That was written in 1974, but I’m pretty sure nothing much has changed on that one. The evolution of life must have this as its headline: in the beginning, God created the heavens and the earth.