Read and listen to the story of NPR’s visit to the Comparative Ocular Pathology Lab of Wisconsin — maybe the world’s largest library of eyeballs and eye parts, with more than 56,000 specimens from aardvark to zebra and back again. COPLOW takes in about 20 new specimens each day, examining tissues and tumors and injury sties to help veterinarians diagnose their animal patients and adding to their collection of samples open to researchers studying the eyes of birds, mammals, fish and insects.