Evolution of Evolution — Text-only | Flash Special Report
Interview with Massimo Pigliucci
What do we know about natural selection that we didn’t know in Darwin’s time?
Today, we know a lot more about natural selection in the sense that we have actually had quantitative studies of natural selection and their field condition in a variety of organisms, plants and animals. We have large statistical summaries that tell us how the dynamics of natural selection changes in different environments and in different species. We also are beginning to understand how, in fact, organisms react to their environment in ways that are much more rich than what Darwin had access to. So, we begin to understand the ecology that actually causes natural selection and we also have an understanding of the genetics and molecular biology that allows living organisms to respond to natural selection. Darwin did not have available a theory of heredity.
What are some of the impressive biologic discoveries you mention in your essay?
In terms of discoveries, I think the two fundamental things that have been going on and they are unfolding right now are the genomics and sort of post-genomics revolutions, the proteomics and metabolomics and similar things. These are providing us with a huge wealth of data on how organisms work at the fundamental molecular level and, of course, that interacts with evolutionary theory because it provides the mechanistic basis for evolutionary changes. The other major area of sort of explosion of studies in biology that I feel are related to evolution is the field of so-called evo-devo, or the evolution of development. There, we have discovered the fundamental things such as that there is a fairly small number of master genes that seem to have – to play key roles in controlling fundamental aspects of development across a wide range of organisms from insects to vertebrates.
You say these new discoveries may lead us to a new evolutionary synthesis.
Well, the current version of evolutionary theory, it’s called the Modern Synthesis, and it came about between the 1920s and the 1940s. The Modern Synthesis, itself, was built on the original Darwinism. It brought together new disciplines such as genetics and, in particular, population genetics, which were not – were unknown at the time of Darwin, but since the Modern Synthesis of the 1940s, much has happened in biology, including the explosion of studies in evo-devo and in molecular biology and the genomics revolution that I mentioned earlier, and all of this has brought to the surface new phenomena of which we knew nothing about before. It also has brought along new ways of thinking about how organisms evolve. Now, this is not in any contradiction with the modern synthesis or, for that matter, with Darwinism itself. It’s just an expansion, I think, a dramatic expansion of the way biologists look at the complexity of the biological world.
How does the concept of “evolvability” square with Darwin’s uniformitarianism?
Scientific ideas evolve themselves over time and we retain the core that works and we discard things that don’t work. The people that worked on the Modern Synthesis of the 1930s and 40s would be surprised to talk about evolvability. The really big question and a controversial one is not really whether there is evolvability or not. The controversial question at the moment is whether evolvability itself changes as a result of natural selection. That is, whether natural selection can improve the way in which living organisms evolve. The answer to that question is rather technical and would take us much more time than we have at the point, but there is no consensus at the moment, and I expect that the discussion, both in terms of theoretical biological work and empirical work, will settle the matter over the next few years.
What will be the next big discovery will be in Biology?
If we were talking about what would be the major discovery in biology that I would hope would take place over the foreseeable future, I would have to say I’m hoping that we will know quite a bit more than we know now about the origin of life. That really is the mystery, an enigma. There are several theories, of course, that address that transition from non-living to living. Darwin, himself, was very puzzled by that question and we know a lot more today than he did but, still, we don’t have anywhere near a clear picture of that transition.