Flamingos Can Only Eat with Their Heads Upside Down

The flamingo's uniquely shaped beak is a highly specialized tool that only functions properly when its head is inverted in the water (Review). With its head upside down, the large lower jaw effectively becomes a trough for scooping up mouthfuls of water. The bird's thick, fleshy tongue then acts like a piston, rapidly pumping water into the front of the beak and forcing it out the sides through comb-like filtering plates called lamellae. This sophisticated system, similar to the baleen plates of some whales, allows the flamingo to sieve its food directly from the muddy shallows.

This efficient filter-feeding method allows them to harvest a diet of brine shrimp, algae, insect larvae, and other microscopic organisms. It is this very diet that is responsible for their iconic pink and reddish hues. The crustaceans and algae are rich in organic pigments called carotenoids, which the flamingo's body metabolizes. These pigments are then deposited into their growing feathers, resulting in their vibrant coloration. A flamingo without a carotenoid-rich diet would eventually molt into dull white or grey feathers, a common challenge for zookeepers who must supplement their food.