Good morning, John!

Around a hundred million years ago, the continent that is currently North America was two or three large islands. And slicing through the space between these islands was a massive, shallow ocean called the Western Interior Seaway. It stretched all the way from the Gulf of Mexico to the Arctic Ocean. And at its deepest, this giant sea was just 900 meters deep. For comparison, the deepest point in the Mediterranean Sea is 5,000 meters deep.

It was warm, it was shallow, there were rivers from all over the place dumping nutrients into this thing. And today, all over the interior of America, you can still see the remnants of that time. There are these little cylinders, they look like maybe crystallized or fossilized plant parts. But, really, they are the remains of crinoids.

These tree-like filter feeders blanketed that sea. But they were not plants. They were animals. Beautiful animals. And if you've ever wanted to see a fossil come to life, I've got good news for you. Because, one, crinoids are still common on Earth, as they have been for nearly half a billion years. And, two, they do not disappoint in their beauty and oddity. 

Crinoids come in two main flavors today: the stalked kind, which we call sea lilies, and the un-stalked kinds, which we call feather stars. Now, they look more like a kind of coral than anything else. Like, that they would just sit, anchored to one spot in the ocean, filtering plankton out of the water and chillin' out.

But corals are collections of tiny organisms, and corals are very much stuck to one place. Crinoids are animals. They are macro organisms like us and they can, though they don't often, move. Oh, yeah. I mean, I maybe forgot to mention the main thing about feather stars, which is this. Like, you've probably seen viral videos of this movement, but it isn't the kind of thing that, like, it hurts to watch again. 

Crinoids spend almost all of their time sitting in one spot. But they spend almost all of their viral video time engaging in this amazing, mesmerising locomotion.

Like other echinoderms, like starfish, sea urchins, sea cucumbers, etc., feather stars are pentaradially symmetrical. They have five-sided symmetry. This is harder to see in crinoids, but it is a thing. They might have any number of legs, but that number should be divisible by five, except that they often get their legs chewed off or knocked off. They are pretty delicate but they could just grow them back.

And while feather stars move around looking like the most unearthly gorgeous thing that has yet happened, sea lilies, which are essentially the same thing--like, they're different species, but very similar--when they move around... yeah, they just drag their stalk behind them. Just trudging across the ocean the ocean floor!

And check this out: Their blood--they have a vascular system--their blood is just water. It transports oxygen and nutrients and waste. It does the whole vascular system thing. But it's just seawater.

We're talking about an organism that figured out how to its thing before blood existed and is still doing that. 

But crinoids have continued to adapt. Like their locomotion--that wasn't happening 500 million years ago. That's relatively recent. I mean like 200 million years ago, but still.

Crinoids, y'all did it. Good work. Just keep swimming, I guess, is what this is.

If you're a member of the Bizarre Beasts Pin Club, we sent out feather stars early instead of armadillos. If you're wondering whose fault that mix-up was: wonder no longer!

Thank you for being a part of that project. All the money from that's going to help some of the most vulnerable people in the world. Just so that everybody knows, the DFTBA warehouse and store have been closed down. Everybody is still on staff. We hope to be up and running soon. 

John, this episode was a really great break for me. I hope it was for you as well, and I'll see you on Tuesday.