A file photo of an Australian lungfish, named Granddad, on display at Chicago’s Shedd Aquarium. The 4-foot-long and 25-pound fish, believed to be the longest-living fish in a zoological setting, was euthanized due to old age. Shedd estimates Granddad was more than 90 years old. The aquarium acquired him from the Sydney Aquarium in Australia during a 1933 collecting expedition and Granddad was one of two lungfish that attracted visitors during that year’s A Century of Progress International Exposition in Chicago. Aquarium officials estimate more than 104 million people saw Granddad over eight decades. Lungfish can live up to 100 years and are a protected species in Australia. The species has existed for more than 380 million years and has not changed for 100 million years, according to the aquarium. (Photo/Agencies)
