Multiple fixed restriction-site differences genetically defined six regional bananaquit populations: Jamaica (JA), Central America (Costa Rica and Panama; hereafter CA), Venezuela (VE), southern Lesser Antilles (Grenada and St.
The mean mtDNA sequence divergence separating continental from all eastern Antillean bananaquit populations was 0.
There was no relationship between mtDNA haplotype and bananaquit color phase, whether the island samples were considered separately (for Grenada: G = 2.
The geographic distribution of bananaquit mtDNA haplotypes indicates that the species has had a complex history in the Caribbean region.
On the other hand, in the bananaquit, which in the West Indies occupies much of the same geographical range and habitats as the mangrove cuckoo, there was mtDNA support for genetic distinctiveness of some of the named subspecies.
An important finding of our study is that levels of mtDNA differentiation between regional groups of bananaquit populations were higher and showed greater phylogeographic structure than those typically observed among avian con-specifics in temperate regions.
Three groups of bananaquit populations, representing southern Central America, northern Venezuela, and the eastern Antilles taken as a whole (Puerto Rico to Grenada), are approximately equally differentiated from each other (average [d.
Judging from the distinctiveness of the Jamaican bananaquit population and the absence of the species from the Yucatan Peninsula and Cuba, it appears more likely that the colonization of the eastern Caribbean islands proceeded from South America rather than from northern Central America through the Greater Antilles.
Multiple fixed restriction-site differences were also found between continental populations separated by only a few hundred kilometers, suggesting that reduced vagility is also characteristic of continental bananaquit populations.
Like most of the Caribbean islands Cuba has fewer species of potential competitors than continental Central and South America, over which the bananaquit is widely distributed.