Falconiformes

The order Falconiformes is a group of 290 species of birds that include the diurnal birds of prey. This group isn't widely accepted by either the American Ornithologist's Union[?] or most European and Australian authorities.

The most common arrangement is to separate falcons and Caracara as a separate order still called Falconiformes, and put all the other groups in an order Accipitriformes.

The American Ornithologist's Union (http://www.aou.org/AOU/birdlist.html) leaves Falconidae and Accipitridae in Falconiformes, but places Cathartidae, in Ciconiiformes.

Falconiforms are known from the Middle Eocene and typically have a sharply hooked beak with a cere (soft mass) on the proximodorsal surface, housing the nostrils. Their wings are long and fairly broad, suitable for soaring flight, with the outer 4-6 primaries emarginated.

Falconiformes have strong legs and feet with raptorial claws and an opposable hind claw. Almost all falconiforms are carnivorous, hunting by sight during the day or at twilight. They are exceptionally long-lived, with low reproductive rates.

The young have a long, very fast-growing fledgling stage, followed by 3-8 weeks of nest care after first flight and 1-3 years as sexually immature adults. The sexes have conspicuously different sizes and monogamy is common.

Problems

Some taxonomies massively enlarge the order Ciconiiformes to include all birds of prey, and often some other groups, most frequently Procellariiformes.

DNA studies mean that it is likely to be some time until a consensus is restored on this group of birds. See Sibley-Ahlquist taxonomy.

External links and references

• http://www.eeb.cornell.edu/winkler/botw/falconiformes.html as of 2002-06-01