Maybe:
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.
But then again, maybe not:
This loss isn’t universal among dedicated meat eaters, though. Red wolves, Canadian otters and aardwolves (hyena relatives that stalk termites) turn out not to have lost their genetic sweet spot.
…[And] from the opposite point of view, some animals that don’t specialize in meat nevertheless may have lost their ability to taste sweetness. For instance, chickens, which eat both plant and animal foods, don’t seem to notice sweetness in their food and appear to lack the functional sweet gene, says Peihua Jiang, also of Monell and a coauthor of the new study.
Chickens are just one reason that Huabin Zhao of Wuhan University in China isn’t convinced by the meat-eater/sweet-loss scenario. He has found sweet loss among vampire bats, which are blood feeders. Narrow diet specialization might be a better explanation, he suggests.
From ScienceNews
Further Reading: [PNAS] abstract available