Helen Fields » evolution

museum tourist: Linda Hall Library

Helen — Mon, 01 Feb 2010 05:11:05 +0000

When I was in Kansas last weekend, we skipped over the border to Missouri to see a nice exhibit of rare books from the History of Science Collection at the Linda Hall Library. This library is kind of a surprise – when we were there, I assumed it was part of a university, but it’s actually an independent public library of science, engineering and technology. Herbert and Linda Hall had a lot of money, and this is what they left it to: a public library.

The exhibit shows the tradition of natural history that Darwin came from. His theory of natural selection was based on years of careful study of different kinds of animals – he knew more than anyone about barnacles, for example, and of course there were his famous Galápagos finches. Natural history is a darn good way to learn about nature.

Most of the displays were illustrations from books back to the 15th century. Back then, people were sort of conflicted between relying on classical texts – it was the Renaissance, they were really into that stuff – and observing plants and animals in nature.Some of the pictures had clearly been done by people who had never seen the animal in question, and the texts often came from the ancient Greeks. But eventually they started figuring out that they should actually be observing the animals they were writing about. (Whoa! Crazy talk!)

This adorable hedgehog was in a 1551 book, Historia Animalium:

Isn’t it spunky? (The label says “bristling with charm.”)

Here are some copepods from a book published in 1820 in Geneva. Copepods are teeny crustaceans – relatives of crabs and shrimp.

I was excited to see these guys because I saw a lot of copepods in the Bering Sea last spring. I wrote stories about copepods on at least four days, but see this day for some really nice copepod portraits. (My fingers got really, really cold while Chris was taking the pictures of the glow-in-the-dark copepods, so be sure to go appreciate the beauty.)

This Portuguese Man O’ War was collected in the deep sea in the 1820s.

That is one pretty jellyfish.

From a book published around 1860, a gorilla:

The gorilla was only scientifically described in 1847. Doesn’t that seem late? I mean, gorillas are really big! And that scientific description was just based on bones; apparently no Westerner saw a live gorilla until the 1850s. Chimps and orangutans were already pretty well known by then. (You can read a little gorilla history in this 1988 newsletter – it’s the first story.)

The library had a copy of On the Origin of Species on display, but I failed to take a picture of it because, um, it was just words, see. There were no pretty pictures of animals. Oops.

So, instead, I will leave you with a picture of my best Scrabble play ever, that night at my aunt and uncle’s house:

I played “EQUINELY” for 239 points. This was made possible by two factors: (1) my uncle doesn’t play defensively, so he put that Q right up there by that triple word score, and (2) in our rules, you can look up words before you play them. I wouldn’t have taken a chance on “equinely” if this had been a challenge game, but I thought it might be a word, and I checked the scrabble dictionary, and it was. Woo. Hoo.

For all my Museum Tourist posts, click here.

photos: me, and they aren’t that good, are they? books behind glass. kind of a rough subject.

turtles taste like chicken

Helen — Fri, 10 Jul 2009 04:18:29 +0000

Yesterday I wrote about turtles. Turtles are awesome. Their shell is made of bone. Bone! Ok, the part you actually touch, the outside, is made of – guess what – tortoiseshell. It’s something like horn. But under that, the hard stuff is made of ribs and vertebrae, fused together. You can see it in the green turtle skeleton at left – sea turtles like this one have big holes in their shell because they don’t really need as much shell as land turtles. (In a land turtle skeleton, that would all be solid.)

Anyway, the truly wacky thing about this arrangement is that the shoulder blades are in front of the ribs. In front! That is weird! As evolutionary morphologist Ann Burke told me: “If you take a deep breath and shrug your shoulders, you realize how bizarre it would be if your shoulder blades were stuck inside your ribcage.” Tetrapods like you and me and cats and birds, we pretty much all have more or less the body plan. But not the turtles. They’re all, “Hey, watch, guys, I can put my ribs behind my shoulder blades.”

I was using my highly sophisticated technique for finding sources who are named in the references of an article – googling burke turtle evolution - and it seemed like, whoever I named, I would get a link to this article from creation.com. So, that’s interesting. Several scientists I talked to mentioned that turtles do more or less spring fully formed into the fossil record. To creationists, that means someone must’ve placed them there.

This whole thing really made me want to go down to the National Museum of Natural History and look at the turtle skeletons. It’s very old-school: a big long hallway with unsexily displayed skeletons, like this. I love it.

art credit: FCIT

P.S. Hey, I just noticed: this is my 100th post on this blog! Howdya like that?

how to catch a pacu

Helen — Tue, 30 Jun 2009 18:32:28 +0000

Yesterday I wrote for ScienceNOW about how piranhas got their pointy teeth. The main thing I learned about piranhas is, really, they aren’t that bad. I talked to two people who have spent a lot of time catching piranhas in the wild and neither has been bitten, other than a little friendly snapping when the piranha was already out of the water. One had a friend who was bitten, though, and it was kind of nasty – the fish took out a chunk of flesh and the guy had to go to the hospital.

I was writing about this guy, Megapiranha – he’s a 3-foot-long extinct piranha relative with interesting teeth. (If you are a person who is interested in piranha evolution.)

Also totally cool: the pacus, which are related to piranhas and look a lot like them, but don’t eat meat. To quote John Lundberg, one of the ichthyologists I talked to: “They really are frugivores. It’s pretty amazing. The pacus that are in the Amazon and Orinoco, they’ll go into flooded forests during the high water season and they’ll wait underneath fruit trees that are coming into maturity. They’ll just hang out. The fruits drop into the water and they float away. Of course the fishermen see that and they fish with fruit.”

Isn’t that funny? Forget nightcrawlers, somebody get this fish a nice juicy piece o’ fruit. He says he watched fishermen in Suriname take a really long pole and put a piece of fruit on the end – something that looks kind of like a kiwi – and slap the fruit on the water. The pacus totally go for it.