Most birds can’t taste sweetness
Most mammals perceive five tastes: sweet, sour, bitter, salty, and umani. On the tongue of mammals, such as humans, there are four types of taste spikes: circumvallate papillae, foliate papillae, fungiform papillae and filiform papillae. papillae). Each papilla can contain 5,000 – 10,000 taste buds.
In fact, every part of the tongue can taste all five flavors. As people age, some taste buds stop periodically renewing. Therefore, the elderly only have about 5,000 taste buds, so the perception of taste will be weaker.
A special point, spicy is not a taste. Scientists have named five official tastes that many mammalian tongues perceive as sweet, sour, bitter, salty, and umani. While spicy is a pain signal, nerves in the tongue send signals to the brain, warning of burning, painful conditions.
Many mammals cannot perceive all five flavors such as felines and marine mammals. However, most vertebrates can taste sugar because they possess the TR1 gene family. The pair T1R1 and T1R3 help animals detect amino acids, organic compounds that make up the perception of delicious meat. While the pair T1R2 and T1R3 detect sugar that helps species perceive sweetness.
However, Ms. Maude Baldwin, a graduate student at Harvard University, discovered that birds do not possess the T1R2 gene, so they cannot taste sugar. This species still senses amino acids.
Studying the genomes of 10 species of birds, from chickens to hummingbirds, Baldwin explains, birds can’t taste sweetness because they evolved from carnivorous dinosaurs. The diet of this species is rich in protein and amino acids but lacking in sugar. Gradually, their T1R2 gene disappeared. As for birds, they do not have this gene at all, so they cannot perceive sweetness