This entry was originally posted on February 17, 2010.
In this video conversation, Jeff Schloss discusses different meanings of the term “evolution” and observes that some of these are disputed and some are not. For example, genetic change over time is not even a theory; it is simply an observation—we see it. But whether that change over time has resulted in the diversity of species we see now—that is an interpretation of the facts. But, Schloss emphasizes, it is an interpretation that is accompanied by overwhelming scientific evidence—ranging from biogeographic evidence to the more recent discovery of genetic fossils. Further, he notes that this idea—that evolution results in the diversity of species—is firmly established and it is central to our understanding of how organisms work and how they are structured.
Then there is a theoretical aspect to evolution that is not fully settled even among scientists themselves. This meaning of evolution asks what the causes are that drive the evolutionary process. While the synthetic theory of evolution, which suggests that evolution results from the twin processes of mutation and natural selection, is the dominant theory, scientists are not fully in agreement with regard to the extent that other factors play a significant role in evolutionary change.