It sure looks like it.  A jogger spotted the bone near Pier Cove off Lakeshore drive just south of Douglas.  It was handed over to the State Police who are doing a forensic examination.

If it is a jawbone, where did it come from?

On theory is this.  On July 12th the body of a Chicago man washed up on the beach not far away.  As gruesome as it sounds,  he'd been in the water quite a while and his body may have been breaking up.

State Police examiners should be able to tell before much longer.