It occurred to me that the usual anti-evolution protest of “There are no intermediates in the fossil record!” is kind of like looking at a spectrum cast out of a prism:
Optics-Denier: “Well, I see red and I see blue, sure, but there are no transitional colors.”
Optics-Proponent: “How about yellow?”
OD: “Well, see, now you’ve actually made the problem worse. Now there’s a gap between red and yellow and a gap between yellow and blue.”
OP: “Okay, well, how about green? Look, there’s green right there.”
OD: “What green? Where? I see yellow and blue. There is no such thing as green light coming from white light. Show me a blue light that reflects red, and then I’ll believe what you claim about optics.”
Now, the analogy isn’t perfect. Each individual color has a “common ancestor” with the others — the white light hitting the prism. But we can’t really say that green is a closer relative to blue than is red, since the colors all diverged from the white light at the same time. But aside from that, dealing with deniers of evolution is a lot like this.
It wouldn’t matter if this was fringe stuff. But lots of folks claim to disbelieve evolution. It’s like disbelieving gravity — how long can you listen to someone say something like that without speaking out?