The heart of a blue whale, the largest animal alive, weighs more than 1,300 lbs (590 kg) and is as big as a small car. Its heart beats 8 to 10 times a minute, and you can hear the beat from over 2 miles (3.2 km) away. Their arteries are so wide that a person could swim through them.
When a blue whale is born, it's already 25 ft long, which is as big as an adult killer whale, and it drinks up to 150 gallons (568 liters) of milk a day. In its first year, it can gain about 200 lbs (90 kg) a day. Blue whales mostly eat krill, tiny sea creatures, consuming 4 to 6 tons daily. They can grow up to 110 ft (33 m) long and weigh as much as 180 tons as adults.
What's amazing is that the biggest animal to have ever lived on Earth is not from the distant past, but is alive today, roaming the vast oceans.
