People visit the Underwater Beauty exhibit at the Shedd Aquarium in Chicago, the United States, on Feb. 17, 2020. The aquarium contains 32,000 animals and attracts around 2 million visitors every year. (Photo by Joel Lerner/Xinhua)

Sharks are seen at the Wild Reef exhibit at the Shedd Aquarium in Chicago, the United States, on Feb. 17, 2020. The aquarium contains 32,000 animals and attracts around 2 million visitors every year. (Photo by Joel Lerner/Xinhua)

People look at the Wild Reef exhibit at the Shedd Aquarium in Chicago, the United States, on Feb. 17, 2020. The aquarium contains 32,000 animals and attracts around 2 million visitors every year. (Photo by Joel Lerner/Xinhua)

Magellanic penguins get fed at the Shedd Aquarium in Chicago, the United States, on Feb. 17, 2020. The aquarium contains 32,000 animals and attracts around 2 million visitors every year. (Photo by Joel Lerner/Xinhua)