What Is the Largest Mammal in the World?

The blue whale, or Balaenoptera musculus, is the largest known mammal in the world as of 2014. Adult blue whales measure from 82 to 105 feet in length, and they weigh up to 200 tons.

The blue whale is the biggest animal in recorded history. Its heart is estimated to be the size of a small car, and the blue whale's tongue weighs the equivalent of an elephant. Even a newborn blue whale weighs up to 3 tons and measures approximately 25 feet in length.

The spray from a blue whale's blowhole can reach up to 30 feet into the atmosphere.