Tuesday, November 27, 2012

Meskwaki- An Important Piece of Iowa's History

When we think of natural history, we tend to imagine fossils and fish, animals with ferocious teeth or giant claws, old bones and shark teeth. I think of Rusty and his friends – the mastodon, the woolly mammoth – and the Devonian section. 
But natural history is more than just the history of extinct animals – it’s a way to catalogue our world, even as it changes.  At the tail end of the Iowa Hall gallery – past the prehistoric fish, the swampy jungle, and Rusty himself – you’ll find a diorama of a Meskwaki settlement, circa 1850, or right after Iowa became a state.  It’s an important marker of Iowa’s past, and filled with interesting artifacts to explore.
 
In the main diorama, an old man teaches a young boy how to carve wood – they sit inside a winter lodge, which the Meskwaki built every winter, using a wooden frame and a covering made of dried cattails.  Nearby, a woman makes a dye (although it looks like she’s cooking).  Her cotton dress, and the wool blanket inside the lodge, point to ongoing trade with settlers – after the first forays of Marquette and Joliet, the first explorers to set foot on Iowa soil, trade among Native Americans and settlers was inevitable. 
Yet I find the more interesting artifacts in the nearby cases.  Beaded artwork abounds – the beads were obtained via trading, but the artwork itself is entirely Meskwaki.  Bows and arrows – even toy arrows for young boys to practice with – and children’s toys cover the bottom of the gallery. And perhaps the most interesting artifact is the necklace made of bear claws and fur.  Only worn by tribal leaders, the bear claw necklace is made from twenty to thirty bear claws, but the claws have to come from a specific paw, so that each bear claw necklace comes from four or five bears.
It’s easy to get distracted by Rusty and Dunky, the vast dioramas that seem to take us to another time – sometimes, the Meskwaki exhibit seems like yesterday in comparison. But what happened yesterday is just as important as what happened last week, or three weeks ago, or three million weeks ago. Iowa’s history is both prehistoric and historic – made up of both the fossils and geodes we unearth from the soil, and the people who came to live here before us, who left traces of their life behind, so we might someday know about who walked in our footsteps.  Shells and arrowheads, projectile points and milling stones: just as fossils and bones tell us about the animals who prowled around, so too do these artifacts.
After all, we weren’t the first ones to set up shop in Iowa. Who wouldn’t want to know about those who came before? That’s what the museum is for.

-Written by MNH Volunteer Catherine Babikian

Tuesday, November 20, 2012

How to Stump a Set of Scientists


To say we were stumped when a visitor stopped by with this object on Friday would be an understatement.  As you can see from the picture, it’s mostly spherical, about 5½” in diameter, and shiny, as if its been polished.  You can’t tell this from the picture, but it’s pretty lightweight, and the impression you get if you pick it up is that it’s hollow.  It was found floating in the Des Moines River about 60 years ago, and the owner stumped museum staff with it then as well.  This time, he asked staff at the UI Paleontology Repository and the Museum of Natural History before someone at the Office of the State Archaeologist finally solved the puzzle. 

We think this is an enterolith, or intestinal stone, presumably from a horse (our research suggests that they are common in horses, but found in some other animals too).  Enteroliths are a lot like gallstones or kidney stones in people, and also something like pearls in oysters.  They form in a horse’s intestines when the chemical conditions are right.  Most enteroliths seem to be formed of a mineral called struvite (ammonium magnesium phosphate), which forms crystals in concentric rings around some starting “seed” (as a pearl does around something like a grain of sand).  Horses seem to get them when they’re eating relatively high concentrations of protein (for example from alfalfa), which generates ammonium ions, and magnesium.  So enteroliths are more common in some places than others because the minerals in soil and water are different and because common food sources are different.  Small enteroliths can be passed naturally, but large ones need to be removed surgically.  According to an equine vet we asked about this, they are often much larger than this one, and they’re usually quite solid and heavy—they are, after all, stones!  That means we haven’t quite solved the mystery of this enterolith (if that’s what it is), because it feels light and hollow.  We wonder whether the mineral crystals inside the enterolith could have been dissolved by immersion in the river, leaving the hard shell… and if any chemists, veterinarians, or taphonomists out there want to do this experiment, we look forward to hearing what you find.

-Written by MNH Associate Director Trina Roberts
 
Examples of other enteroliths

Tuesday, November 13, 2012

A Visit to Undersea Iowa


A trip through Iowa Hall is very much a trip through Iowa’s past – step in the galleries and you’ll see Iowa before it became farmland, before highways and roads began to criss-cross the state, before Iowa City was even a city at all. 

After many, many trips through Iowa Hall myself, I’ve decided that some exhibits in the gallery are easier to fathom than others.  We know of the Native Americans who used to live on the land, before settlers came; we can even believe that Rusty, tall and large as he is, used to live in an Iowa covered by glaciers.  (After all, sometimes the winter feels like the Ice Age.) But it’s harder to believe that Iowa was once a tropical swampland, and that it was once underwater, harder still.

The Devonian exhibit is the first in Iowa Hall, and it’s a true glimpse into an Iowa that’s long gone: Iowa from 360 million years ago, covered in shallow, sunny waters, filled with ancient cephalopods and armored fish? It’s true.

The armored fish in question would be Dunky – short for Dunkleosteus – a prehistoric fish who used to rule the seas. We think sharks today are scary, but a shark would have paled in comparison to Dunky (there is a shark in the Devonian exhibit, but it’s far smaller), who as an adult would have been two stories tall and the length of a school bus.  He could open his jaw as wide as it would go, and it would create so much pressure that anything in the vicinity would have been sucked in – this even included other fish.


Trilobites, the first animals to develop eyes, were around in this period, too – although they went extinct at the end of the Devonian, the exhibit is home to many – as are ammonites, which also went extinct.  Ammonites, which look similar to cephalopods, had huge, hollow shells, and the ammonite could slide its body in and out, controlling its buoyancy and position in the water.  If it’s hard to believe these animals really existed, it’s harder to believe they once lived in Iowa, a place very much out of water – but the fossils never lie. 



Dunky and the trilobites aren’t the only things in the exhibit – there are plenty of animals that today you might find on coasts or coral reefs. Huge expanses of coral, like what today you might find in Australia, cover the exhibit, as they would have covered the ocean floor (coral, interestingly enough, is actually an animal).  My favorite, however, would have to be the crinoids, or sea lilies.  They look like underwater flowers, but are actually delicate animals that use the ocean currents to catch small, microscopic organisms to eat.

But it’s this varied, sometimes unbelievable history that makes Iowa’s past interesting – it’s the idea that Iowa hasn’t always been farmland and rolling hills, but instead a glacial paradise, a quasi-rainforest, or a shallow sea.  And that’s why, even after countless trips, Iowa Hall is still a fascinating place – we’ll never get to see Iowa as anything but prairie and farmland, but step through Iowa Hall and you’ll get amazingly close.

-Written by MNH Volunteer Catherine Babikian