Evolution of Evolution — Text-only | Flash Special Report
Interview with Richard Lenski
What do we know about evolution that we didn’t know in Darwin’s time?
The fact that all life derives from a single primordial origin, Darwin wasn’t sure about that and so he has a passage at the very end of “The Origin” where he talks about life, modern living organisms, being descended from one or a few living things, but we now know that all living organisms are descended from a single primordial ancestor. A second thing that we’ve learned today that Darwin knew nothing about was heredity, the mechanisms of how genes are – how phenotypes are inherited from one generation to the other. Darwin was very smart and knew that there was some mechanism of heredity but his attempts to explain heredity were utter failures.
What makes bacteria particularly useful in the study of evolution?
Bacteria are wonderful for studying evolution for several reasons. The most obvious one, and the one that attracted me from switching many, many years ago from working on insects to working on bacteria is they reproduce so quickly. I have a project that’s been going on for about 20 years in the lab and during that time, the E. coli we study have gone through over 45,000 generations. So, it’s possible to actually watch evolution in action in the laboratory under controlled settings using E. coli.
What breakthroughs have you had in your bacteriological research?
One that got a lot of attention last year was that our bacteria in the flask that I just showed you, they’re growing on a sugar, a very familiar sugar, called glucose but throughout these tens of thousands of generations, we had another source of energy that, in principle, bacteria can use, a certain species of bacteria can use but E. coli is a species that’s unable to grow on this other carbon source, which is called citrate, and a few years ago, one of our 12 replicate populations evolved this new capacity to grow on this substrate citrate that E. coli, as a species, is not able to grow on, and this was an inherited trait so that after that trait emerged, all of the subsequent generations within that population have continued to have that trait.
Will humans have greater effect on future evolution than nature?
I’m not sure I would say greater. I mean, first of all, there are always laws of nature that bind everything, from robots to humans, genes, ecology, everything, and second of all, I guess I would just simply say we are a part of nature. We have changed nature, we have emerged from nature, we have powers of our thought and our culture and the ability to transmit things across generations not in our DNA, but in books about science and music and art. We’ve changed the way in which nature now operates in fundamental ways and that gives us this important stewardship.
What will be the next big discovery in biological sciences?
But we are a part of nature. But I think those, in terms of particular areas that I’m excited about, one is one that I’m involved in a little bit and I mentioned before, which is this idea of taking evolutionary principles and applying it to non-biological realms of computer science, engineering, robotics. There are other people actually evolving artwork and evolving architecture, and so on. So, I think that that transplant of Darwin’s ideas into other realms, using other substrates, is extremely exciting going forward.