Two groups of whales evolved massive heads for different reasons

By Jake Buehler

A bowhead whale (Balaena mysticetus) successful the Sea of Okhotsk, Russia

Tony Wu / naturepl.com

Bowhead and close whales are among the biggest animals live today, but a caller look astatine however they evolved suggests that these 2 intimately related groups ballooned successful size independently, and astir apt for antithetic reasons.

Both are balaenids, a benignant of baleen whale (a classification that includes the gigantic bluish whale), but they aren’t shaped similar different baleens. They person stocky bodies and immense heads that tin instrumentality up a 3rd of their assemblage length, and their mouths are …