Mar 30, 2008

Our Ice Age Animals

Imagine the Greater Cincinnati area about 20,000 years ago.  The temperatures were much cooler.  Summer temperatures averaged around 41-degrees Fahrenheit and winters hovered around 10-degrees, with an annual average temperature of

26-degrees (compared to today’s average of 56-degrees).  We did not have the deciduous forests of today with our many oak, maple, walnut, hickory and beech trees.  Instead our forests were coniferous, dominated by spruce and balsam.  Grasses were common creating an almost park-like setting, with many lakes, bogs, marshes and canebrakes.  Cool breezes would blow off of the retreating ice sheet; an ice sheet that was up to a half-mile thick in central Ohio.

 

“The Ice Age, or Pleistocene Epoch, lasted 2 million years,” said paleontologist Dr. Glenn Storrs, Assistant Vice President for Natural History and Science at the Cincinnati Museum Center.  “There were four pulses of glaciation.  The last one, the Wisconsinan glacier, began to recede about 20,000 years ago.”  Glaciers have designed our landscape.  “We are a city of valleys not hills,” said Dr. Storrs.  “Our rivers and their flow, our fertile valleys and clean water are a direct result of glaciation.” 

 

The mega fauna (large animals) during the Ice Age were extraordinary.  Elephants, true elephants called mammoths, roamed our valleys along with their relatives the mastodons.  “Greater Cincinnati was home to the Wooly Mammoth, the Columbian Mammoth and the Mastodon,” said Dr. Storrs.  “To my knowledge we are the only place in the country that has documented an over-lapping range of these three species.”  Mammoths and mastodons were about 9 to 10 feet tall and weighed up to 3 tons.  They were herbivores though they did not compete with one another for food, as fossil remains show mammoths as grazers and mastodons as browsers.  “The mastodon was a much more common animal here than the mammoth,” said Dr. Storrs.  “Like modern elephants, both were likely social.” 

 

Saber-tooth Cats may well have been hunting our mammoths, mastodons and other prey.  “They were probably here,” said Dr. Storrs.  “Fossil remains of the Saber-tooth Cat have not been found in Kentucky or Ohio, but they have been found in Indiana and Pennsylvania.”  These fierce predators were about 5 feet long and had two huge canine teeth, or sabers, that were probably used to cut or slice open bellies of prey. 

 

Another predator, the Dire Wolf, would have been roaming about.  They were about the same size as modern wolves, with a heavier build.  These social predators would form packs and hunt species like caribou, elk and deer.

 

The largest predator found in the tri-state during the Ice Age was the Giant Short-faced Bear.  “It was a very large, long limbed fast moving bear,” said Dr. Storrs.  “It was much larger than today’s bears, standing 6-feet tall at the shoulders and was primarily a meat eater.” 

 

Ancient Bison were very common in our area 20,000 years ago.  “Ancient Bison were about 30% larger than modern bison,” said Dr. Storrs.  Interestingly, scientists have concluded that Ancient Bison actually evolved into today’s modern bison.  By the end of the Ice Age food supply was changing with climate.  Ancient Bison naturally evolved into modern bison, as modern bison are smaller and require less food.

 

Another fascinating Ice Age animal was the ground sloth, with both the Jefferson’s and Harlan’s Ground Sloth occurring here.  Jefferson’s Ground Sloth was the largest at 8-feet tall.  Ground sloths were huge, bulky, slow moving herbivores with peg-like teeth.  “It is believed that black locust and honey locust trees developed an evolutionary defense against ground sloths and mastodons with thorns that grow on the trunk of these trees,” said Dr. Storrs.

 

Giant Beaver lived in the many lakes, bogs and marshes formed by the melting ice.  “Giant Beaver were three times larger than modern Canadian Beaver,” said Dr. Storrs.  “They did not build dams like Canadian Beaver. They ate rushes, cattails and cane.”  Giant Beaver lived more like muskrats than today’s Canadian Beaver.  Their teeth were notched at the ends and were probably used to clip cattails and grasses, whereas modern beaver have teeth that are flat at the ends and work like chisels in cutting wood.

 

Other now extinct large animals found in our area included the Woodland Musk Ox, Complex-toothed Horse, and the giant Elk-Moose, which had the head of a deer and the body of a moose.  Flat-headed Peccaries were very common, forming large family groups, or herds, in open woodland areas.  Birds, including Giant Condors with 12-foot wingspans, would have been flying the skies as well.  “Many of these species were first described to science from fossils found at Big Bone Lick, Boone County,” said Dr. Storrs.

 

So what happened to these amazing animals, why did they go extinct?  As the climate warmed we gradually moved from a coniferous forest to a deciduous forest, changing plant life.  Many animals simply lost the types of plants they ate.  Some of the animals followed the plants north, but those plants had a shorter growing season allowing the animals less time to feed themselves and their young.  Our area also became more hospitable to humans, who in turn hunted these large animals contributing to their demise.  “Extinction took place over a period of several hundred to several thousand years,” said Dr. Storrs.  “At about the time these animals went extinct humans came to the area.  Humans were here by at least 11,000 years ago.  By 9,000 to 10,000 years ago all of the mega fauna was extinct or moved to the north.” 

 

Many animals survived though and continue to live amongst us.  Our turtles, salamanders, woodchucks, muskrats, raccoons, opossum, flying squirrels, fox squirrels, bald eagles, golden eagles, black vultures and pileated woodpeckers are all survivors from the Ice Age, to name a few.  Some animals survived only to become extinct as Europeans settled the New World.  The Passenger Pigeon and Carolina Parakeet were both Ice Age relics.  Sadly our forebears hunted both to extinction, with the lone survivors of both species dying in the early 1900’s at our Cincinnati Zoo. 

 

What does this say about today’s climate change, is it just a natural phenomenon?  “The earth is a dynamic and changing place with large amounts of time involved and people need to be appreciative of this,” said Dr. Storrs.  “Current climate change is happening at a much faster rate than during the Ice Age.”  Case in point, researchers at Stanford University predict that if global warming is not checked, 30 percent of all land bird species could become extinct before the end of this century.  Most alarming is that nearly four-fifths of the species that face extinction are not even listed as threatened or endangered today. 

 

The Ice Age continues in the tri-state area.  The Cincinnati Ice Age exhibit at the Cincinnati Museum Center is a must-see for those who live in and visit the area.  “Our Museum Center’s Glacier exhibit is the best place to see a reconstruction of this area and animals during the Ice Age,” said Dr. Storrs.  “We have the best glacier exhibit in the world.” 

 

 

Contact Gayle at her website for nest boxes at www.woodlandhabitat.com or at yourtown@fuse.net

 

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