It took a set of specific circumstances to allow the blue whale to become the largest of all animals
The blue whale is, famously, the largest animal to ever live.
Think for a minute what that means. According to some estimates, there are about 7.7 million animal species alive today, and who knows how many more have lived on Earth since the first animals appeared about 650 million years ago.
Those species include elephants, whale sharks, polar bears, tyrannosaurs, and titanosaurs - all species with a reputation for large size. But not one of them is, or was, as large as the blue whale.
'Instead of having to spend energy hunting a single prey item like a fish or seal, energy that could be wasted if it escapes, the baleen whales simply glide through dense clouds of krill like aquatic combine harvesters, swallowing up to 457,000 calories in one gulp.'
The numbers in this article are immense