According to a new study just published in the journal Current Biology, penguins can’t taste fish. While the waters of the Arctic are still teeming with fish, penguins’ palettes are reportedly “comparatively crippled.”
A team of researchers from the University of Michigan in Ann Arbor, Michigan, concluded that the flightless birds actually “lack three of the five main taste buds.” They cannot taste anything bitter or sweet. They cannot detect the meat-like taste named umami.
Jianzhi ‘George’ Zhang, a professor in ecology and evolutionary biology at UM stated in a press release that penguins “eat fish, so you would guess that they need the umami receptor genes, but for some reason they don’t have them. These findings are surprising and puzzling, and we do not have a good explanation for them. But we have a few ideas.”
In examining the palette-specific section of a penguin’s genome, the investigative team discovered that penguins lost the capability of discerning bitter, sweet and umami flavors more than 20 million years ago. Every species of penguin have this in common.
This evolved loss of taste buds however makes a lot of sense. Prior research indicates that the specific protein Trpm5—which is required for the transfer of bitter, sweet and umami flavor signals from their tongues to their brains—does not work very well in cold temperatures. Zhang said: “This gives us a hint, perhaps, that this loss of taste genes has something to do with the inability of this protein to work at lower temperatures.”
Additionally, penguins suck down fish whole. This generally bypasses any opportunity their tongues would have to do any real tasting anyway.
Zhang concluded: “Their behavior of swallowing food whole, and their tongue structure and function, suggest that penguins need no taste perception, although it is unclear whether these traits are a cause or a consequence of their major taste loss.”
Penguins Can’t Taste Fish