Frozen Reign: When Indiana’s landscape was sheets of ice and oversized animals

By Peggy Fisherkeller, Curator of geology, Indiana State Museum

and Ron Richards, Senior research curator of paleobiology

Fifth in a series on major changes being made to the Indiana State Museum as it works to better educate visitors about the past and present of the Hoosier State

This scene depicts a common sight on prehistoric Indiana: A mastodon struggling to avoid death.

A heavy rod of darkened steel ties together the entire length of the backbone and neck, each vertebra perched jewel-like upon a custom mount.  Four huge legs hugged by steel frames support the backbone. Crowned with a 350-pound skull and lower jaw, the 13,500-year-old bones of Fred the Buesching mastodon introduce the history of life and environments in Indiana.

Three newly redesigned galleries will open Saturday, March 24, at the Indiana State Museum. One – Frozen Reign: A State of Change – will highlight ancient environments in a fresh way, interpreting a time when Indiana was populated by antagonists from a disaster movie: Indifferent ice sheets that tore up our landscape and oversized Ice Age animals – both predators and prey.

We see the effects of the Ice Age every day. From the hilly northernmost dunes, to the mostly flat middle, to the rugged southern part of the state – glaciers have shaped our landscape.

The most recent Ice Age began 2.58 million years ago and lasted until 11,700 years ago. It wasn’t a period of constant cold. Instead, the climate fluctuated, with 50 or more temperate-cold cycles. Glaciers expanded and receded. Animals and plants adapted to changing conditions, often moving to follow their preferred temperatures and environment.  In Indiana, only the last two or three cycles are preserved in the form of fossils and glacially deposited sediment. The evidence from these cycles forms the heart of the gallery experience.

Peggy Fisherkiller stands in the ice tunnel, where an icy wind will help visitors imagine the landscape so many thousands of years ago.

To explore just how powerful glaciers can be and foster appreciation for these rapidly disappearing resources, we created an ice tunnel in the exhibit inspired by continental glaciers in places such as Iceland and Greenland. Set 17,000 years ago when the great Wisconsinan Continental Ice Sheet was in retreat, the first scene shows plants and animals slowly repopulating the rugged till plain that had recently been covered by glacial ice. Icy streams emerged from beneath the glacier. The landscape was a thawing, moving mixture of water and dirt.

As visitors approach the entrance to the ice tunnel, they will feel an icy wind blowing off the top of the glacier. Animals able to tolerate living so near the ice front – a snowshoe hare, snowy owl, and tundra muskox – energize the scene.

Inside the tunnel, there are sounds of ice crackling and water trickling. The ceiling, scalloped from warm winds, is luminescent, distilling light from outside.

Many think of the Ice Age as a time when land was covered with moving glacial ice, but that was not always true.  There were warmer phases as glacial ice melted back toward the north, and “interglacials” where the climate was as warm as or warmer than presently.

One scene, termed the “Jaguar’s Den”, shows events that occurred in a southern Indiana cave 115,000 years ago. The remains of the real site were cast, so we can present the actual appearance of the den, with a large jaguar hovering over its recently hunted prey – the carcass of a peccary it had dragged down through the entrance of the cave onto a large slab of limestone.  Outside the cave are the bones that allowed us to reconstruct this scene and a tooth of a saber tooth cat, whose remains were also  found in the cave.

Next in the exhibit, another ancient event plays out in a deep pit inside a Southern Indiana cave. The ripe scent of a dead peccary has drawn a dire wolf through dank, twisting tunnels. Limping on a dislocated rear leg, the wolf has leaned too far over the edge of a pit where the scent was strongest. Falling 20 feet into the water, he is now trapped in the darkness along with his meal. The actual pit was cast on-site, showing the exact cave features where the museum excavated the bones.  In a simulation of being underground, the visitor can hear sounds that the dire wolf may have experienced. Nearby, finds from recent excavations can be seen through fissures in the cave walls.

Indiana is a mastodon state where remains of these giants lie beneath the soil of almost every county.  A unique wall arrangement lays out all the mastodon bones found during a single dig

Curator Ron Richards stands amid mastodon skeletons.

conducted in 2000. Complete with 8-foot-long tusks and massive skull and hips – and a seemingly unending cage of ribs – the bones are arranged so the visitor can discover which bones are present and which are missing.

Next in the gallery, guests can see the giants of Indiana’s Ice Age face-to-face, including a giant ground sloth. This 9-foot-long beast is a distant relative of the inoffensive modern tree sloth.  Equipped hand and foot with massive claws, it weighed in at more than 2,500 pounds. Visitors will be able to feel one of its huge claws, used for grasping limbs or defending itself from predators.

Finally, visitors will witness an unforgettable event in northern Indiana 12,300 years ago. As you stand on the shore of a kettle lake, a large mastodon looms into view, moving cautiously onto the frozen surface. With the sharp crack of breaking ice, the terrified beast suddenly trumpets, shocked by immersion in icy water.  Feeling the vibrations of its trumpeting, you shake helpless as it struggles vainly to gain a foothold and escape. Startled, a nearby sandhill crane launches into flight, and a fisher not far away freezes, now distracted from stalking a vulnerable porcupine. A distant herd of caribou looks on.

How do we know this?  We have the bones!

Dramatic climatic and environmental change has taken place during and after the Ice Age, with accompanying cycles of different species-rich communities, and a final extinction of most of North America’s large mammal species. Together, the bones of these now-extinct animals, along with those that no longer live here, help us understand life in Indiana over thousands of years.

 

 

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