Flamingo

Many molecular and morphological studies support a relationship between grebes and flamingos.

Recent molecular studies have suggested a relation with grebes,[10][11][12] while morphological evidence also strongly supports a relationship between flamingos and grebes. They hold at least 11 morphological traits in common, which are not found in other birds. Many of these characteristics have been previously identified on flamingos, but not on grebes.[13] The fossil palaelodids can be considered evolutionarily, and ecologically, intermediate between flamingos and grebes.[14]

For the grebe-flamingo clade, the taxon Mirandornithes ("miraculous birds" due to their extreme divergence and apomorphies) has been proposed. Alternatively, they could be placed in one order, with Phoenocopteriformes taking priority.[14]

Living flamingos:[15]

Six extant flamingo species are recognized by most sources, and were formerly placed in one genus (have common characteristics) – Phoenicopterus. As a result of a 2014 publication,[16] the family was reclassified into two genera.[17] Currently, the family has three recognized genera, according to HBW.[18]

Image	Species	Geographic location
	Greater flamingo (Phoenicopterus roseus)	Old World	Parts of Africa, S. Europe and S. and SW Asia (most widespread flamingo).
	Lesser flamingo (Phoeniconaias minor)		Africa (e.g. Great Rift Valley) to NW India (most numerous flamingo).
	Chilean flamingo (Phoenicopterus chilensis)	New World	Temperate S. South America.
	James's flamingo (Phoenicoparrus jamesi)		High Andes in Peru, Chile, Bolivia and Argentina.
	Andean flamingo (Phoenicoparrus andinus)		High Andes in Peru, Chile, Bolivia and Argentina.
	American flamingo (Phoenicopterus ruber)		Caribbean islands, Caribbean Mexico, southern Florida,[19] Belize, coastal Colombia, northern Brazil, Venezuela and Galápagos Islands.

P. croizeti fossil

Prehistoric species of flamingo:

• Phoenicopterus floridanus Brodkorb 1953 (Early Pliocene of Florida)
• Phoenicopterus stocki (Miller 1944) (Middle Pliocene of Rincón, Mexico)
• Phoenicopterus siamensis Cheneval et al. 1991
• Phoenicopterus gracilis Miller 1963 (Early Pleistocene of Lake Kanunka, Australia)
• Phoenicopterus copei (Late Pleistocene of W North America and C. Mexico)
• Phoenicopterus minutus (Late Pleistocene of California, US)
• Phoenicopterus croizeti (Middle Oligocene – Middle Miocene of C. Europe)
• Phoenicopterus aethiopicus
• Phoenicopterus eyrensis (Late Oligocene of South Australia)
• Phoenicopterus novaehollandiae (Late Oligocene of South Australia)

American flamingo and offspring: The arcuate (curved) bill is well adapted to bottom scooping.

Flamingos filter-feed on brine shrimp and blue-green algae as well as insect larvae, small insects, mollusks and crustaceans making them omnivores. Their bills are specially adapted to separate mud and silt from the food they eat, and are uniquely used upside-down. The filtering of food items is assisted by hairy structures called lamellae, which line the mandibles, and the large, rough-surfaced tongue. The pink or reddish color of flamingos comes from carotenoids in their diet of animal and plant plankton. American flamingos are a brighter red color because of the beta carotene availability in their food while the lesser flamingos are a paler pink due to ingesting a smaller amount of this pigment. These carotenoids are broken down into pigments by liver enzymes.[27] The source of this varies by species, and affects the color saturation. Flamingos whose sole diet is blue-green algae are darker than those that get it second-hand by eating animals that have digested blue-green algae).[28]

Chilean flamingo feeding its young

Colony of flamingos at Lake Nakuru

Flamingos are very social birds; they live in colonies whose population can number in the thousands. These large colonies are believed to serve three purposes for the flamingos: avoiding predators, maximizing food intake, and using scarcely suitable nesting sites more efficiently.[29] Before breeding, flamingo colonies split into breeding groups of about 15 to 50 birds. Both males and females in these groups perform synchronized ritual displays.[30] The members of a group stand together and display to each other by stretching their necks upwards, then uttering calls while head-flagging, and then flapping their wings.[31] The displays do not seem directed towards an individual, but occur randomly.[31] These displays stimulate "synchronous nesting" (see below) and help pair up those birds that do not already have mates.[30]

Flamingos form strong pair bonds, although in larger colonies, flamingos sometimes change mates, presumably because more mates are available to choose.[32] Flamingo pairs establish and defend nesting territories. They locate a suitable spot on the mudflat to build a nest (the female usually selects the place).[31] Copulation usually occurs during nest building, which is sometimes interrupted by another flamingo pair trying to commandeer the nesting site for their use. Flamingos aggressively defend their nesting sites. Both the male and the female contribute to building the nest, and to protecting the nest and egg.[33] Same-sex pairs have been reported.[34]

After the chicks hatch, the only parental expense is feeding.[35] Both the male and the female feed their chicks with a kind of crop milk, produced in glands lining the whole of the upper digestive tract (not just the crop). The hormone prolactin stimulates production. The milk contains fat, protein, and red and white blood cells. (Pigeons and doves—Columbidae—also produce crop milk (just in the glands lining the crop), which contains less fat and more protein than flamingo crop milk.)[36]

For the first six days after the chicks hatch, the adults and chicks stay in the nesting sites. At around 7–12 days old, the chicks begin to move out of their nests and explore their surroundings. When they are two weeks old, the chicks congregate in groups, called "microcrèches", and their parents leave them alone. After a while, the microcrèches merge into "crèches" containing thousands of chicks. Chicks that do not stay in their crèches are vulnerable to predators.[37]

The first flamingo hatched in a European zoo was a Chilean flamingo at Zoo Basel in Switzerland in 1958. Since then, over 389 flamingos have grown up in Basel and been distributed to other zoos around the globe.[38]

Greater, an at least 83-year-old greater flamingo, believed to be the oldest in the world, died at the Adelaide Zoo in Australia in January 2014.[39]

Zoos have used mirrors to improve flamingo breeding behaviour. The mirrors are thought to give the flamingos the impression that they are in a larger flock than they actually are.[40]