Bowhead whale surfacing © Michael Nolan : Robert Harding / Getty
An adult bowhead’s head accounts for approximately two fifths of its body length. These Arctic giants specialise in particularly small crustacean prey, so they need a large amount of baleen to filter sufficient quantities from the water.
About 640 baleen plates hang from its upper jaw and, at 4m in length, they are the longest of any whale’s – hence the need for a super-sized head.
Calves don’t develop these front-heavy proportions until they have been weaned. Their bodies virtually stop growing for a few years as they channel resources into their front ends. The youngsters even dismantle bone tissue laid down in their ribs while they were suckling and redistribute it to the skull and baleen areas to accelerate growth.
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