African Pygmy Falcon, Africa
A previous post already described how falcons and hawks evolved independently of each other about 80 million years ago, the former in South America, the latter in Africa. In addition to the many similarities between the two distinct groups of raptors, there are some curious parallel species pairs. Among those are the smallest members of each group: the African Pygmy Falcon and the Pearl Kite. (The previous post highlighted the Bat Falcon and Bat Hawk, among others.)
Pearl Kite, Latin America
Both the African Pygmy Falcon and Pearl Kite are around 8 to 9 inches long and prey on lizards, birds, insects, and other small prey. They also both stand out because they are bright white below (unusual for raptors), gray above, have a lot of white in the face (most notably on the auriculars), and a reddish splash on the body (on the back in the falcon, on the flanks for the kite). The kite is so similar to small falcons that it was originally thought to be a falcon until detailed analysis proved otherwise. Unsurprisingly, they both perch in open, swooping on their prey from an elevated perch. They also have similar high-pitched repetitive calls, described as kik-kik-kik-kik for the falcon and pip-pip-pip-pip for the kite. As small non-migratory raptors, each have remained on their home continents– the falcon in Africa and the kite in South America (and into Central America).
It’s also worth noting some convergent parallels to shrikes, another unrelated raptor. The Pygmy Falcon flight is especially shrike-like.
Deep Nature: exploring convergent evolution 