A long, long, long time ago...

I would like to say I can talk to you on an intimate level about mammal-like synapsid reptiles or the evolution of tetrapods. But I can't; I have a passing familiarity with them, but really only passing. For example, while writing this post, I was about to refer to edaphosaurus and dimetrodon as pelycosaurs. I had no idea that that term had fallen out of favor with scientists over the last ten years. Thank goodness that Wikipedia saved me from that potentially embarrassing faux pas.

And what exactly can I say about ancient fish-like amphibians? Not very much. I read Stephen Jay Gould's Eight Little Piggies years ago (it's still on the shelf, but the scholarship is probably hopelessly out of date now), and I know that ancestral tetrapods likely had a whole mess of digits – way more than our sets of five. I also know that jaws likely evolved from gill arches and our inner ear bones evolved from spare jaw bones. But how to tell the difference between acanthostega, ichthyostega, panderichthys, temnospondyls, tiktaalik, and the rest? I'm not your guy*. Although I absolutely love reading about them and imagining their life histories and possible evolutionary relationships.

Clockwise from top left: Edaphosaurus, Crassigyrinus, Panderichthys, Dimetrodon

It's also fun to imagine what they were thinking about. How they felt and who they were friends with or who liked to play head games! What did they talk about and why did it matter? Does it make a difference that in some cases they were separated by tens of millions of years? For example, about 100 million years separates panderichthys and dimetrodon from each other. That's about 35 million years more than separates you and tyrannosaurus. But it all happened before people existed and prehistory has a remarkable way of flattening itself out in the imagination. My own lifetime makes sense to me in that I can imagine time in blocks measured in decades. That makes sense to me. But millions of years? That's just numbers. In my mind they all lived A Long Time Ago. So I'm free to put them together, make them friends or antagonists. Edaphosaurus can have insecurities about his neighbor crassigyrinus even though they are separated by about 100 million years. Give or take.

Here is a group of four handsome (or lovely, if you imagine they are ladies) creatures. They are posing for the camera, showing you their good side. There is obviously some sort of conversation going on here, but what are they saying. And to whom? And do you care as much as I do?

PS Happy New Year! Of course, what's one more year when we've been thinking of the heady notion of hundreds of millions of years?

*Okay, so I mostly know the difference between most of those, but they are still downright confusing to me. Depending on how the artist chooses to restore them, they can be unrecognizable from one illustration to the next. They exist as abstractions in my mind, unlike, say, a stegosaurus, which is very concrete no matter what colors the artist uses.