Evolution of Evolution

Evolution of Evolution

If we take a look at the process of evolution, many anomalies could crop up, but most have turned out to be explainable. Thus, Piltdown man was always an embarrassment, because he did not fit into onto any reasonable human evolutionary tree. At last chemical analysis showed that Piltdown man was a hoax. Without the great guiding principle of evolution in general, who would have paid attention to him at all?

Likewise, we have seen the evolutionary principle in sometimes tragically practical application today, as pathogenic microbes gain immunity to antibiotics through the selfsame process of natural selection that Darwin found. On a still deeper level, we find that we can best understand the details of protein chemistry as between different species (for instance, cytochrome-c) in terms of their differentiation through geological time; but it was the concept of evolution that caused researchers to look for such divergences in the first place.

So we have very briefly reviewed the development of evolutionary thought – the evolution of evolution, so to speak – and seen how fundamental it has become to biology. Now we must return to the comparison with physics, and to the philosophy of science in general.

As we have seen, theories are subject to disproof. Else they would have no meaning. (Thus, if I told you that space is pervaded by a fluid so subtle that no instrument or experiment can possibly detect it, you could not prove me wrong, but you would not be obliged to take me seriously, either. As a matter of fact, this is precisely what happened to the luminiferous etcher about which 19th century physicists had speculated. It turned out to make no difference whether the ether existed or not; therefore nobody had any further reason to imagine that it did exist).

Voyages from sun to sun will always be few, women's love for the shoes will always exist. Photo by Elena.

Thus many theories have fallen by the wayside. But some reveal themselves, in the course of time, to be more fundamental than that. They become basic principles, by which theories themselves are tested. They become touchstones by which observations are evaluated. They become a context within which everything else, in a given field of science, is understandable.

Examples within physics are the two laws of thermodynamics, already mentioned. Without them, we simple could not make sense of our observations of any process involving energy exchange. With them not only do we comprehend what we see, we are led to new discoveries.

For instance, back in the 1930s, physicists noticed certain curious features of recoil during radioactive decay. The energies and momenta did not balance our as they were supposed to. Either the principles of energy (and momentum) conservation were wrong, or else some ultra-tiny particle was involved, carrying off the excess. Rather than give up their basic principles, which were far too helpful to discard, scientists hypothesized that such a particle did exist: the neutrino. This idea proved fruitful in gaining more knowledge of the nucleus – although not until a generation later was the neutrino actually detected, and then only indirectly.

Granted, basic principles originate in empirical observations. Indeed, the laws of thermodynamics came out of grubby engineering work, and rather late in the history of science at that. Nor are the basic principles Holy Writ. They are subject to modification as our knowledge grows. Thus the separate principles of conservation of mass and energy were unified – modified – into the single principle of the conservation of mass-energy, by Einstein.

However, such principles become so fundamental that the complete overthrow of any of them would mean the complete overthrow of the sciences with which they are concerned. We would be practically back to Square One. It is therefore both understandable and sensible that scientists will not – cannot – set them aside without an absolutely overwhelming, and hence unlikely, body of evidence.

I submit that evolution is no longer a mere theory.

(By Poul Anderson).

Our very survival, let alone our eventual modernization, is in doubt. Where evolution will eventually lead us? Photo by Elena.