How do ducks eat without teeth?
Ducks have to swallow their food whole – from soft plant stems to tough nuts and seeds. But ducks (and all birds) have a secret weapon to help digestion: a gizzard. The gizzard is a sac between the duck’s stomach and intestines. The walls of the gizzard have strong muscles with lots of ridges. Food passes into the gizzard from the stomach, where it’s already been softened up a bit by mixing with digestive juices. Then, the gizzard’s walls squeeze together. This squeezing grinds the food between the ridges, breaking it down. Tiny stones called grit also get stored in the gizzard (ducks eat the grit on purpose). The sharp edges of the stones further break down the food as they grind against it.
