Mourning Doves
What special ability do these birds share with flamingos and penguins?


Mourning Doves have the ability to produce a nutritious food called "crop milk", which is fed to their young. A bird's crop is a sack-like structure above the stomach. It lets the bird gulp down food, which is temporarily stored in the crop. This reduces the time that birds spend on the ground feeding.

Doves with young develop a layer of cells lining their crops. These cells are richer in fat and protein than cow's milk, and they slough off to produce a very nutritious food for baby doves. Unlike mammals, both parents produce crop milk. At first, the adults don't eat, so the crop milk will not be contaminated by other foods. As the babies grow, they eat more and more seeds, which soften and are fed to the young along with the crop milk.

Greater Flamingos and Emperor Penguins have the ability to produce similar food for their young.