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M is for Mary Anning

Mary Anning statue in Bristol, bristol.acl.uk

She sells seashells by the seashore,
The shells she sells are seashells, I’m sure.
So if she sells seashells on the seashore,
Then I’m sure she sells seashore shells. 

Mary did sell seashells. She was well-known for doing it at the time, though only locally, and never credited by the male scientists who took her work and used it to gain their own notoriety. They say the poem is about her, although it probably was not. Yet she did, indeed, sell seashells, found seashells, drew seashells, theorized about the age of seashells, and drew plesiosaurs. By the Lyme Regis seashore.

She also invented paleontology.

Current Lyme Regis map, southampton.ac.uk.

Mary, Mary

No, that’s another rhyme…. although her garden grows with cockle shells, so maybe… And it may be that she did not exactly invent paleontology, but paleontology didn’t exist as a scientific discipline until she collected hundreds of fossils and starting drawing, mounting, and discussing them with others. And after that it did.

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L is for Living Relatives

Dinosaurs could see in color. The EPB-living relative theory says so. Picture by Sergey Krasovskiy.

EPB. Remember those letters when you think of dinosaurs. They’re hard words–extant phylogenetic bracket–which I will define shortly. But they are like a magic wand for paleontologists and paleobiologists. EPB lets scientists looking at fossil bones, those 100-million-year old rocks, tell what kind of muscles they had, whether their blood vessels were strong, and whether they could see in color. Scientists can tell all sorts of things about the soft tissues inside those bones because they can compare them to the closest Living Relative. (I was going to include this under letter E, but I had to talk about extinction, so I’m slipping it in here under L. By inference, which is how EPB works.)

EPB: Big Words, Brilliant Idea

Let’s break this acronym down. Extant is the opposite of extinct, so that refers to something living, in particular a species or group of animals (remember C for Clade). Phylogenetic is a mouthful. Phylo means group and genetic refers to a group. Bracket also means group.

extant (living) + phylogenetic (group evolutionary tree) + bracket (group) = EPB

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K is for the K-Pg Boundary

An image from a simple Google search for “dinosaurs.” From earthspacecircle.

You probably have heard about the asteroid. Big BOOM. You can’t really look at a generic picture of dinosaurs on the Interwebs without seeing them fleeing from hellfire and brimstone. But the asteroid involves two parts. The latter part is what happened after the BOOM, and I’ll tell that story toward the end of the alphabet. You’ll have to guess what letter.

But the first part of the scientific part of the story is how did they know? How could scientists tell that there was a big giant asteroid that eliminated all the dinosaurs? Maybe they could figure out from the fossil record that the dinosaurs disappeared. But how did they know it was caused by an extraterrestrial event? Particularly when the impact crater was, as it turns out, deep under water?

They didn’t know at first. The scientific method triumphed in the end. And fathers and sons.

The Old Ideas of Catastrophe

Before 1980, paleontologists did know that dinosaurs disappeared, around 64 million years ago, in fact. The end of the Cretaceous period was set at 64–and not 100 or 150–precisely because that was when all the dinosaur fossils disappeared.  It was somewhat handy that it happened during a chalky geological period since that made it easy to spot on the sides of cliffs.

The layers of geology. White is the KT boundary. Graphic from geowyoth.
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