The Blue Whale is the largest animal to ever inhabit earth. It’s uncertain how many remain, estimates are between 10,000 – 25,000. Their tongues weigh as much as an elephant, hearts as much as a car. They reach 100 feet in length, and live up to 100 years. Ponder this – the world’s largest animal sustains itself on one of the world’s smallest, krill. Krill is no bigger than a shrimp. A single Blue Whale eats nearly 4 tons every day.