avianwing

The distribution of Parrots and Cockatoos across the world can be summarized in terms of no. of species as

Australia-IndoPacific islands- 170
Mainland Asia- 15
Africa- 25
South America and Caribbean- 150

The high diversity of Lorikeets in New Guinea and Australia is partly attributed to the absence of Primates. Similarly Black cockatoos partially replace woodpeckers.

Is there any reason why Africa and Mainland Asia have a very poor diversity of parrot family birds. It is very intriguing.

TomboyMom

I am just pulling this out of my derrière, but Australia also has marsupials rather than placentals in part because it broke off from South America before placentals evolved. Are parrots perhaps a relatively old genus or whatever they are, and in Asia other species are filling ecological niches filled by parrots in Australia?

avianwing

I guess there are more open niches left for parrots to fill. There are many species of grass parakeets , ground feeding parakeets, much rarer even in the parrot dense South America. The high diversity of parrots in Oz and SA can be explained by studying the various niches.

But the low diversity in Asia and more so in Africa is what puzzles me. What could be the bird taxa which are replacing the parrots??

Woodpeckers- Black Cockatoos is of course one
Primates- Lorikeets is the other but that still does not explain high diversity of parrots in South America
Asia has only medium sized Parakeets which are similar to Conures of South America and Rosellas of Australia.
The Large Parrots like Amazons, Cockatoos and Macaws are entirely missing in Mainland Asia while Only one truly large parrot-The Grey exists in Africa. The rest are medium sized or dwarf lovebirds.

Monad

Just out of interest is the Grey related more to the S American species or the Asian ones? It seems to be quite distinct though to me it looks closer to the American species but maybe that's convergence?

Monkey Wrench

Monad, It's just convergence. See here; http://en.wikipedia.org/wiki/List_of...s_%28family%29 The Gray Parrots are not only in a different genus than the Amazonians, but they are grouped into a different "tribe" ( I've never heard tribe used in cladestics before...?)

I believe primates reach South America late, its been speculated that they reach South America by "rafting" .This would have an effect on evolution as monkeys compete for the same food sources as parrots. I'll try to find a link.

http://cacajao.tripod.com/platyrrhine.html