A string of mammals that eat a lot of meat have lost the power to detect sweetness
As a rough rule of tongue, animals that have lost the power to taste sweetness tend to be specialized meat eaters.
A gene crucial for detecting sweet taste carries disabling glitches in seven of 12 mammals analyzed in a new study. The sweet-blind animals are spotted hyenas, Asiatic small-clawed otters, two catlike wild hunters (fossa and banded linsang), sea lions and two kinds of seals — all predators.
A sweet detector probably wouldn’t give these carnivores much of an advantage as they hunt their dinner, speculates study coauthor Gary Beauchamp of the Monell Chemical Senses Center in Philadelphia. So mutations in that sweet detector gene, Tas1r2, could easily spread through populations, Beauchamp and his colleagues propose March 12 in the Proceedings of the National Academy of Sciences.
This loss isn’t universal among dedicated meat eaters, though. Red wolves, Canadian otters and aardwolves (hyena relatives that stalk t