If you are among the 40% of Americans who do not accept evolution as a fact of life — that evolution is indeed a fact and not “just a theory” — or if you have even the slightest doubt that Charles Darwin’s theory of natural selection accurately explains the diversity of life on this planet, you must see a PBS NOVA presentation titled What Darwin Never Knew. It will open your eyes to how our world really works. This television program offers the clearest explanation I have seen not only of Darwin’s theory itself, but also many of the subsequent scientific discoveries that have reinforced that theory. You should watch this show even if you are already convinced that Darwin was right because you will be delighted by the clarity with which the evidence, both old and new, is presented.

Many have suggested that Charles Darwin should be credited and praised for coming up with “the best idea that anyone has ever had.” That accolade may be deserved more today than ever before.

Each new scientific advance in the fields of genetics and embryonic development (evo-devo) has provided and continues to provide new lines of evidence that support the fact of evolution and the theory of natural selection.

What fascinated me most about What Darwin Never Knew was the discussion surrounding DNA switches that turn genes on or off. The narrator tells us, “We now know that DNA works in many different ways, through genes that make the stuff of our bodies, through switches that turn those genes on and off, and through sequences of DNA’s chemicals that throw those switches. Taken together, what this all adds up to is a way that we can, at last, understand how small differences in DNA can generate enormous change.”

Katie Pollard, a biologist who is an expert on the DNA of chimpanzees, explains: “Given all the obvious differences between humans and chimps, you might expect our DNA to be really different. But, in fact, it’s more like 99 percent identical. … Basically, you can make massive changes, just changing those switches. So a small change, a couple of DNA letters, could have a profound effect.”

We’ve heard people say “it’s all in the genes,” but perhaps the more accurate trope is “it’s all in the gene switches.”

What Darwin Never Knew may be watched online HERE, and the DVD is available through Netflix.