![]() ![]() Shape - similar proportions, often with a longish tail, rounded to pointed wings for either maneuvering or hovering.Thus, any similarities between hawks and falcons is due to convergent evolution. In ecological adaptations is the parallel evolution of diurnal predators in the two clades, Accipitriformes in Afroaves and Falconiformes in Australavis. This becomes evident when comparing the ecological adaptations of bird groups in Afroaves with those in Australavis…. Because of a general similarity in major habitat types between the continents, several specializations evolved in parallel in different phylogenetic lineages. In each continent different bird groups responded to the local conditions by evolving a range of ecological adaptations. It can be postulated that after the break-up of Gondwana in the Cretaceous the terrestrial avifaunas of Africa, South America and Australia were more or less isolated from each other for many millions of years. 2012. Evolution of terrestrial birds in three continents: biogeography and parallel radiations. (Thanks to their ability to fly, both hawks and falcons have since spread around the world.)įrom Ericson, P.G.P. Actually, each got a bunch of them– and the parallels include many details and sub-examples at the species level. It was if each place needed a diurnal raptor for their ecosystem, and each got one. After the breakup of Gondwana over 100 million years ago into Africa, Australia, and South America, hawks evolved in Africa and falcons evolved in South America independently of each other. Well, if you go back millions of years they are related in the same way that songbirds and owls are related (which is very very distantly).Įssentially, the story is this. Near the top of this list of DNA-discovered examples of convergent evolution is the conclusion that Falconiformes (falcons and caracaras) and Accipitriformes (which includes eagles, hawks– both Buteos and Accipiters, kites, harriers, and Old World vultures) are not related to each other. It now seems that convergent evolution is practically the norm rather than the exception– that various groups of species once thought closely related (and put adjacent to each other in field guides) are not related after all– that they each evolved, convergently but separately from each other, to serve a similar role in the ecosystem on different continents, though many have since spread out over each other. However, recent DNA analysis has blown the lid off this idea. It used to be that there were a few obvious examples of convergent evolution in the bird world– like meadowlarks and longclaws- and then a bunch of lesser known examples for which this blog is dedicated, in part, to illustrating. Here is the dramatic rationale behind it. The Pygmy Falcon flight is especially shrike-like.īirders are well-aware of the recent change in their checklists, which annoyingly relocates the falcons away from hawks, eagles, and other diurnal birds of prey, and puts them deep among the little birds– just before flycatchers. It’s also worth noting some convergent parallels to shrikes, another unrelated raptor. 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). 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. Unsurprisingly, they both perch in open, swooping on their prey from an elevated perch. The kite is so similar to small falcons that it was originally thought to be a falcon until detailed analysis proved otherwise. 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). 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. ![]()
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