Complex sentence: Such concerns about what he views as the oversimplification of genetics led Lewontin to be a frequent commentator in debates, and he has lectured widely to promote his views on evolutionary biology and science.
Split into simpler sentences: Such concerns about what he views as the oversimplification of genetics has led Lewontin to be a frequent participant in debates, and an active life as a public intellectual. He has lectured widely to promote his views on evolutionary biology and science.