Image property of the Royal Ontario Museum
…Because of their giant hearts.
With each beat of it’s heart the blue whale pumps 60 GALLONS of blood, which is pretty impressive, especially when you compare it to the average human heart, which only pumps 2.4 ounces beat!
Like the rest of the blue whale’s body, their hearts are massive and on average weight as much as a cow, around 1000 lbs, however this one only weighs about 440lbs.
In 2014 a Blue Whale carcass was discovered onshore in Newfoundland and was still in good condition for scientists to preserve its heart. Take a look at this interesting Wired.com article about the process of preserving such a massive organ.