Wilderness Underfoot: Nine creatures that have lived in our state

StoryImage( ‘/Images/Story//Auto-img-111583501911915.jpg’, ”, ‘Jellyfish – They first arose 600 million years ago in the seas of the Pre-Cambrian Period. The species shown here, Essexella asherae, is half that age. It is found in fossils near Braidwood, Ill. Jellyfish continue to live throughout the world’s oceans.’);
StoryImage( ‘/Images/Story//Auto-img-111583530718952.jpg’, ”, ‘Sharks – Our region was positively swimming with sharks during the later Paleozoic Era. Prehistoric shark fossils are most prevalent in the coal regions of the state, from 300 million years ago.’);
StoryImage( ‘/Images/Story//Auto-img-111583532318952.jpg’, ”, ‘Squids – Having survived in the seas a full half-billion years, they are still alive and doing fairly well. Shown here is Endoceras sp., a 450-million-year-old animal whose fossils are common in limestone and dolomite in the Rockford area.’);
StoryImage( ‘/Images/Story//Auto-img-111583527616593.jpg’, ”, ‘Trilobites – These arthropods were once among the most dominant and diversified animals on the ocean floor, but they lived rich and died poor. First appearing in the early Cambrian, 540 million years ago, they finally went extinct 245 million years ago. You can find fossils of this trilobite, Gabriceraurus mifflinensis, in the same rocks as Endoceras, above.’);
StoryImage( ‘/Images/Story//Auto-img-111583543320850.jpg’, ”, ‘Primitive reptiles – Ancestors of the dinosaurs, the birds and mammals, these animals emerged about 340 million years ago, during the Carboniferous Period. This is Cephalerpeton ventriarmatum, known from a single fossil found in Grundy County, Ill.’);
StoryImage( ‘/Images/Story//Auto-img-111583549018749.jpg’, ”, ‘Dinosaurs – The case for dinosaurs in Illinois is entirely circumstantial. Hadrosaur fossils have been found in Iowa and Missouri; there’s no reason to doubt that they also lived here.’);
StoryImage( ‘/Images/Story//Auto-img-111583554516593.jpg’, ”, ‘Passenger Pigeon – It was once one of the most abundant birds in North America, and very common in Illinois. A single flock could stretch 300 miles across the sky. Ectopistes migratorius was hunted to extinction by 1900.’);
StoryImage( ‘/Images/Story//Auto-img-111583552014709.jpg’, ”, ‘Mammoths – They spread across northern regions about 3 million years ago, adapting to the cold as Ice Age glaciers moved in. The Columbian Mammoth, shown here, went extinct about 12,000 years ago.’);
StoryImage( ‘/Images/Story//Auto-img-111583558116630.jpg’, ”, ‘Bears – The bears and their relatives have been around since the middle Tertiary Period, about 25 million years ago. The black bear, Ursus americanus, inhabited this region until the Civil War period, but it was eliminated in Illinois ‘);

A wonderful assortment of animals have swum, crawled, walked, and flown through our region over time

As history has unfolded, the earth has undergone dramatic changes. Our own region has been covered by seas, filled with dense tropical forests, buried in ice, and dappled with prairies and temperate woodlands. Here’s a small sample of the diverse creatures that have lived in the place we now call Illinois.

From the May 11-17, 2005, issue

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