What is the largest animal to ever exist on Earth?

The blue whale (Balaenoptera musculus) is the largest animal to ever exist on Earth. These massive marine mammals can grow up to 100 feet long and weigh over 200 tons, with a heart the size of a small car.

Blue whales are found in all of the world's oceans and can be identified by their blue-gray skin with white spots. They are baleen whales, which means they filter feed by swallowing massive amounts of water and then pushing it out through their baleen plates to trap and eat small prey, such as krill and small fish.

Despite being the largest animal, blue whales are still vulnerable to threats such as climate change, ocean pollution, and whaling. Conservation efforts have helped the population of blue whales increase, but they are still classified as endangered.