In this Wednesday, June 13, 2012, photo, a group of children are seen at Chicago's Lincoln Park Zoo. Visitors flock to the 49-acre zoo a few miles north of downtown Chicago where the admission is free... more 
In this Wednesday, June 13, 2012, photo, a group of children are seen at Chicago's Lincoln Park Zoo. Visitors flock to the 49-acre zoo a few miles north of downtown Chicago where the admission is free and it's open year round. (AP Photo/Charles Rex Arbogast) less 
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Associated Press | Photo By Charles Rex Arbogast
Thu, Jun 14, 2012 2:09 PM EDT