Why You See Birds On Dirt Roads
There are two parts to a bird’s stomach, each of which has a different function. The proventriculus, or glandular stomach, secretes enzymes that begin the digestive process. Lacking teeth, birds also have a gizzard, or muscular stomach, that grinds up the food that a bird has eaten. For this reason, the gizzard is usually very strong and muscular. Seed-eating birds often eat seeds whole and need to break them into tiny pieces in order to digest them. Many of these birds can be seen on dirt roads, picking up small stones and grit which then collects in their gizzards and helps pulverize the food they’ve eaten. (Photo: American Goldfinches)
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