From “A whale of a story,” Nature 485, 416 (24 May 2012), we learn,
Rorqual whales capture much of their food by an extraordinary procedure known as lunge feeding. When a rorqual comes across a dense patch of prey, it accelerates through the water and open its mouth. As it does so, its mouth fills with water, suspended within which are the tiny animals that the whale wants. The amount of water that flows into the whale can more than double the creature’s weight, and to accommodate it, blubbery pleats under the lower jaw expand, just as an accordion grows as it fills with air. The once sleek and streamlined whale now has the shape of a bloated tadpole. And it has a lot of water in its mouth.
To squeeze the water out again, the whale closes its jaws and pushes the water out through plates of keratin filters, which trap the food. In this way, rorqual whales can gulp and graze for hours, repeatedly slowing down then lunging through the water.
It is a unique process, and one that requires some special equipment. …
But how on Earth does a rorqual manage to coordinate this activity? On page 498, Nicholas Pyenson of the Smithsonian Institution in Washington DC and his colleagues describe a sensory organ that they discovered in the jaws of several species that might offer an answer. More.
Whale evolution time frame too narrow for a Darwinian process …
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