Survival in the Alkaline Cauldrons
For the lesser flamingos that live in Africa’s Great Rift Valley, the region’s caustic alkaline pools are a tasty delight. Where regular folks see a hot cauldron of alkaline mineral salts, the pink-tinged birds see a delicious pea-green soup full of nutritious spirulina—a blue-green algae. To get to the algae however, the flamingos have to filter the water.
This is where the 10,000 thin, sieving plates in the flamingo’s highly evolved bill come into play. The birds first stir the water with their feet and then sway their heads to and fro in the water, using their tongues as pistons to filter 35 pints of water a day through the sieves. At the end of the day, a bird might have gathered two tasty ounces of nutrient-rich spirulina.
When the feeding conditions are good, the birds set out to look for a mate and launch into an elaborately choreographed spectacle worthy of Broadway. With their wing flashes, head flicks, beak nibbles, neck moves, and very distinctive vocalizations, the seething mass of birds acts like a marching band–stepping in time, splitting, reuniting, and changing direction—in a mysterious display that ultimately results in pair bonding and mating.