Helen FieldsScience Writer

I took the occasion of a visit to Colorado last week to drop in on the Denver Museum of Nature and Science. The building opened in 1908, which is positively ancient for Colorado. And like any self-respecting natural history museum, it is chock full of dead animals. As a special bonus, though, they extend this to the human animal. Not only because one of those dead-modern-humans exhibits was on when I was there (this one – I skipped it). The museum also has a nifty little exhibit of Egyptian mummies.

First: A dead reptile of the Mesozoic Era. Or what’s left of it. I thought this Stegosaurus was particularly lovely. I don’t remember seeing those scutes below the neck before. Aren’t they pretty?

This fossil was found in 1937 near Cañon City, Colorado by a high school teacher. They redid the pose after discovering another Stegosaurus skeleton in 1992 – that showed them things like how the back plates and tail spikes were arranged.

You know how birds eat grit to help them digest their food? Dinosaurs did that, too:

They’re called gastroliths.

Check out how tough this fish is. It’s a big predator from the sea that covered Kansas late in the dinosaur era.

See how tough it is? It died with a whole fish in its belly. You can see the tail at left and the vertebrae scattered along toward the right. (The head and everything were there, too.)

On to the dead humans!

In the old days, visiting Egypt was a lot like it is today in some ways. People marveled at the pyramids and the Sphinx. It was really hot. They bought souvenirs. The souvenirs were just a little different, that’s all. Until 1946, a visitor to Egypt could pick up a mummy to show the folks back home. In 1904, a wealthy businessman from Colorado went to Egypt and came home with a couple of mummies. They were displayed in a museum in Pueblo until the last 15 years or so; they’re on long-term loan to Denver now.

In the late 90s, the scientists in Denver took the mummies to get CT scans at a university medical center. (They rode in an ambulance.) This is much less destructive than the old way of figuring out what’s inside a mummy – unwrapping it. Without messing with the linen at all, they could look inside and learn about the people inside. First, this lady:

At some point in her history, somebody thought it was a good idea to unwrap her head. She’s in a very simple sarcophagus, so they had a good bet she was poor to start with. When they did the CT scan, they learned that the mummifiers hadn’t even bothered to remove her internal organs – they just shriveled in place. Her linen covering is only a few layers thick, and there are no charms or amulets wrapped into it.

Another mummy was also in a poor person’s coffin – a poor man’s coffin, from the way it was done. But the CT scan showed that the innards were a wealthy woman.

See the two white things – I think the top one is the heart, wrapped in linen and ready to go for the afterlife. So that’s part of what shows you she’s wealthy. The other part is the thing below that – a scarab tucked into her wrappings. They don’t know how she wound up in the wrong coffin – it could’ve happened in ancient times, or it could’ve been done by the souvenir seller in 1904.

Amazing preparations, aren’t they? The Egyptians took the afterlife seriously. The museum also displayed some of the tools and ornaments people had buried with them. It seems like a waste of effort, but what do I know? I’ll sure feel dumb if I die and get to the afterlife and find out I was supposed to bring my stuff with me.

The museum also has a lovely set of dioramas. There’s a whole room showing all the environments of Colorado, from low-ish desert, through the plains, to the alpine tundra. And a whole section of Botswana – the trip I was planning last year to Namibia and Botswana fell through, so I was able to imagine just a bit of what it would be like by looking at this:

I’m inclined to be a little disdainful of dioramas, but I guess they’re good for imaginary vacations.

For all my Museum Tourist posts, click here.

A few weeks ago when I went to the National Aquarium in Washington, I got quite a surprise: this guy, staring me down from inside his tank.

He’s a northern snakehead, a kind of invasive fish who made quite a splash when they showed up in the Potomac River a few years back. Such a big splash that Smithsonian magazine went looking for someone funny and local to write a story about snakeheads for them, and ended up with me. Here’s the story.

You should go read it, but, to summarize, I went looking for snakeheads with the Virginia fish and game folks, a professional bass fisherman (sponsored by “Team Spouse”), and some guys with a boat, and the only snakeheads I saw were dead at the natural history museum. It was the summer of 2004, and they just weren’t that established in the Potomac yet.

So I was excited to see one in the flesh at the aquarium. They’re pretty well settled into the river now. This one was collected from the river when the Virginia fish and game folks were out on one of their sampling expeditions. Ok, ok, if you insist, here’s another picture:

For all my Museum Tourist posts, click here.

I have an embarrassing admission to make: I love fish, I love aquariums, I grew up in the Washington area, and I had never been to the National Aquarium in D.C. Until today. In my defense, the National Aquarium is basically one big room in the basement of the Commerce department, it doesn’t have a very good reputation, and it is dwarfed by the ginormous, beautiful National Aquarium in Baltimore. But I happened to have a pass for free admission that expired tomorrow, so this afternoon I finally stopped in.

First, let’s dispense with the basement issue. What are you going to do with natural light in an aquarium, anyway? (Ok, the Baltimore aquarium and the Monterey Bay Aquarium do lovely things, I know, I know. But this aquarium gets by without it. So there.) It’s the nation’s oldest aquarium – established in 1873 in Woods Hole, it bounced around a bit over the years, then settled down in the 1930s, after the Commerce building was built. It got a much-needed renovation in the last few years.

Ok, there are no adorable marine mammals. But a lot of people would argue that you shouldn’t have them in captivity anyway. Instead, this aquarium has baby alligators on loan from an alligator farm; when they get too big for the space, they’re shipped back to Florida and end up in the wild, as part of the conservation efforts for the American alligator. Here’s their spiffy Everglades-style habitat:

And let me introduce my new alligator friend:

I like his goofy grin.

Most of the exhibits were about U.S. waters, with a particular focus on the National Marine Sanctuaries – that’s the connection to the building, you know, NOAA and everything is under the Department of Commerce. But they also had a corner about the Amazon, with this awesome snake.

I’ve been told you should never go walking in the rainforest with a herpetologist, because they will point out things like this all the time, when you might have been happier if you’d stayed ignorant. The emerald tree boa mostly eats birds. It gets its teeth into a bird, squeezes it to death, then pokes around until it finds the head (the proper end to start swallowing from).

This tank represents life in Brazil’s Rio Negro. It is appearing in this blog post because it is gratuitously pretty. Also, those are real water plants, not plastic. So that’s nice.

There, wasn’t that pretty?

This gray tree frog lives in North American bogs. Well, not *this* one. This one lives in a tank.

It’s a nice little aquarium. It’s not super flashy and it sticks to the smaller animals, but they’re well presented, and I thought the emphasis on U.S. protected waters was a clever way to focus a small collection. (And then there’s the random Amazon section, but hey, everybody loves the Amazon.)

For all my Museum Tourist posts, click here.

This weekend I was in Lawrence, Kansas, where my dad grew up, and stopped by the University of Kansas Natural History Museum. It’s in a great old building atop a hill on the KU campus.

In olden times (the Cretaceous, if you want to get technical – late in the dinosaur times), Kansas was underwater. The west coast and the eastern U.S. were separated by the Western Interior Sea. I love that it has a name, even if it isn’t a very poetic name – like it’s got a name waiting for it, in case the Rockies decide to go back down.

All that water means Kansas is rich in fossils of wacky sea creatures like this guy:

He’s a Xiphactinus molossus, a kind of bony fish. Doesn’t he look mean?

Also awesome: crinoids.

Crinoids are echinoderms, relatives of starfish and sea urchins that leave behind a lot of hard bits. They make beautiful fossils (a couple of these have been colored to show you what you’re looking at.) There are actually still crinoids, but they’re not nearly as diverse as they used to be.

One of the prized possessions of the museum is Comanche the horse. Dead horse! In a glass case!

Comanche survived the Battle of Little Bighorn in 1876, with several arrow and bullet wounds. After he recovered, he became a mascot for the Seventh Cavalry. He did parades and wandered around Fort Riley, about 100 miles west of Lawrence. When he died in 1891, he was sent off to the University of Kansas to be preserved. In 1893 he – or his skin, anyway – helped represent Kansas at the Chicago World’s Fair.

Here’s a great slide show on his restoration a few years ago. They had to build a full-size model to make sure he’d make the corners on the way to his new exhibit space. I love the pictures of him wrapped in plastic for the move. His head’s sticking out, which is reassuring – you wouldn’t want the dead horse to suffocate.

My dad remembered going to the museum on Cub Scout outings to see the snakes. I checked and, yep, they’ve still got snakes. (Probably not the same snakes as in 1950. No word if Cub Scouts still come look at them, but I can’t imagine they’d miss the chance.) They have fifteen species that are found in Kansas, each in its own cheerfully painted case.

I feel like the common garter snake, at right, got the nicest room. All those cheerful Kansas sunflowers.

The cottonmouth seemed particularly mean.

For one thing, it’s got the triangular head that screams, “I AM VENOMOUS.” Also, there were little furry gray things floating in the water that looked a heck of a lot like bits of mouse. I thought snakes swallowed their food whole, but I don’t know, maybe that one put up a fight.

For all my Museum Tourist posts, click here.

photos: me, of course

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.

art copyright Ray Troll, 2005

Someone helpfully stopped by my post on sardines and left a link to this blog: Society for the Appreciation of the Lowly Tinned Sardine. It includes many lovely photographs of sardine tins on well-appointed plates – apparently you’re supposed to actually smack the opened can down in the middle of all your tasty garden vegetables and stuff. They also seem to put a lot of thought into the drinks paired with the sardines. Huh.

Wow, check it out: chocolate sardines. Don’t worry, there’s no actual sardines inside those wrappers. I hope. If anyone’s in France around Easter, I want some – you hear me?

The other day I was at the grocery store, and I had tuna on my list. It’s easy, it keeps more or less forever, it fits in cans, I can put it on salads. But then when I was actually standing in front of the canned fish, I was hit by this sudden wave of guilt at using giant, long-lived fish at the top of the food chain for cheap protein. I’ve heard many talks in which people who understand the oceans say we really ought to be eating bait fish. (And I’ve been buying tuna all along, so I don’t know why the guilt chose last Saturday to set in.) I looked at the other cans on the shelf.

Which brings me to today’s lunch:

I haven’t quite been able to figure out the full environmental implications of this choice. Fish are confusing. If you look up “tuna” on the Monterey Bay Aquarium’s Seafood Watch website, there are six different kinds of tuna, and whether or not you should buy them depends on how they’re caught. If you look up sardines, they give you two options, actual sardines and atlantic herring – but it seems that what I have is actually a little Atlantic fish called a “brisling” or “sprat,” which the Monterey Bay Aquarium doesn’t cover. (Read about sprat here.)

But I do understand food webs, and sardines are way lower down than tuna are. It’s like eating grain-eating chickens instead of man-eating tigers – it’s a more efficient use of resources. Fortunately, they taste pretty good. I polled my Facebook friends, and the consensus was that they should be on toast. A former choir director also suggested a large whisky and soda. I haven’t added that particular flourish yet, but I can’t imagine a large whisky and soda would make anything worse.

Today I wrote an extremely teensy story for ScienceNOW. It’s at the bottom of this list. It’s about a 300-million-year-old fossil brain. That’s really old. Soft tissue doesn’t usually get preserved, but they found this one with the crazy bright x-rays of a synchrotron.

Those little teeny stories only run with one picture, so I’m really just blogging here to share this drawing of what the iniopterygian (it’s a cartilaginous fish, related to sharks and stuff) might have looked like:

Is it just me, or does this fish look…well…kind of dumb? In a wide-eyed, hopeful way. Sorry bout the extinction, little guy.

Image courtesy of PNAS

Hey, lookit, I blogged. I mean, somewhere other than here. It’s over at ScienceNOW, the daily online news service of Science magazine. The topic: fisheries. Not *all* of the world’s fish are completely doomed. Fisheries scientists have decided that if everyone in the world thinks that all the fish news is totally bad, nobody is ever going to want to do anything about it. (Hey, they’re doomed – let’s just kill ‘em all and have the world’s biggest fish fry.) So they’re embarking on a campaign to tell the good news stories.

You could tell this was kind of a struggle sometimes. I went to part of the scientific session (the blog post was written after the press conference) and Greenpeace guy John Hocevar said, “I’ve been trying to stick to good news but I can’t quite do it.” He hung in there for a while, but then he got to tuna: “Truthfully, the tuna news is mostly bad.” Oh well. He still wrung some good news out of it. And there really are fish success stories.