Ornithologists' understanding of the taxonomic position of falcons, including kestrels of course, has changed greatly in recent years,but they are not placed close to woodpeckers. The current thinking, based mainly on nuclear DNA sequencing, is that falcons' closest relatives are parrots, and seriemas, and then this group, taken together, is the closest relatives of passerines (songbirds).. The latter are 2 species of terrestrial birds from South America that look like small Secretary Birds. They run around on the ground in open country and capture prey like lizards, large insects, small rodents, etc. The most interesting thing about seriemas is that they are the closest surviving relatives of the giant Terror Birds (Phorusracidae) of the Tertiary, terrestrial predators much larger than ostriches.
So this leads us to a picture of a radiation of hook-billed birds in South America that includes falcons, now worldwide; parrots, now pantropical; and terrestrial predators confined tr the Americas, and extinct except for the 2 seriemas.
The current distribution and phylogeny of falcons supports a neotropical origin. Currently most of the falcon species are in the eastern hemisphere, but this is a recent radiation almost all within the genus Falco. The neotropics has fewer species, but has most of the higher diversity within the family, with about 10 genera of caracaras, forest falcons, Laughing Falcons, and so on.
On 6/30/2018 1:46:04 PM, Harry Fuller <atowhee...> wrote:
doesn't the taxonomy and DNA data indicate they are closely related to woodpeckers?
This morning near the Portland airport I saw what seems an unusual sight that I thought I'd share. There were 4 American Kestrels scattered over a moderately sized area, with 2 of them close to each other and interacting. These 2 repeatedly kept flying to and landing on the side of a power pole, just like a woodpecker would. One even seemed to peck at the pole once, but the other times they seemed to just land on the side of the pole, sit for a few moments, and then fly off. After a few minutes they seemed to tire of this game and returned to perching on the wire itself as usual.