Bruce MacFadden is telling a story as if it happened to him. It is the story of the evolution of horses and the portrayal of their evolution in museums across the United States. Fossil horses are one of the finest examples of evolution found anywhere in the fossil record. He knows this story extremely well even though it is riddled with specific terms, processes, and details that are hard to understand and/or remember even in isolation, without the context of how it all fits together. This story has been evolving for over thirty years, starting with his work as an undergraduate. But it is not done. In fact, it may never be complete. What he understands makes sense to him now, but each new finding and fresh analysis changes the story, and affirms or challenges what he understands.
Bruce’s claim is that the information communicated about horse evolution is more often wrong than right. Their evolution is phylogenic, meaning that their lineage has branched off such that, at times, there were several daughter species living concurrently. The depiction of their evolution found in museums and textbooks often shows what he calls orthogenesis, or “straight line evolution”, where one species evolves directly into another. Why the exhibits and texts show it this way is somewhat of a mystery. It has been over a hundred years since horse evolution was proven to be phylogenic. Is it just easier to portray this way? Is it to save space in museum exhibits and textbooks
At the start of Q & A, immediately following a warm applause for Bruce’s talk, one after another audience member poked at what they perceived as holes in Bruce’s work. He was on the defensive, and the attacks were aggressive. To one commenter, he replied “I’d love to argue with you more about that over a beer”, to which the commenter replied, “I’d love that”. This is science, and this is the way it goes. When you put yourself out there, you expose any vulnerable pieces of your claims, or even in the way you told your story. I’d imagine word choice is critical, and I am now understanding better the careful way of communication that I have noticed when Bruce speaks technically.