A penguin’s sense of taste appears to be limited to just sour and salt. Genetic research suggests that of the five vertebrate senses (sweet, umami, bitter, sour and salt), penguins only have taste receptors for sour and salt.
If you were to make a microscopic inspection of a penguin’s tongue, you’d find something fishy. “The lack of taste buds strongly suggests a reduction in taste function,” write the authors of a paper just out in Current Biology. This supposition is supported by their observation that Adelie and Emperor penguins (and by extension all other penguins) only have taste receptors responsive to sour and salt.
