Pylogeography of the Galápagos hawk: a recent arrival to the Galápagos Islands

BOLLMER, J.; KIMBALL, R.T.; WHITEMAN, N.K.; SARASOLA, J.H.; PARKER, P.G.

MOLECULAR PHYLOGENETICS AND EVOLUTION

ELSEVIER

Lugar: Amsterdam; Año: 2006 vol. 39 p. 237 - 247

1055-7903

Galápagos hawks (Buteo galapagoensis) are one of the most inbred bird species in the world, living in small, isolated island populations. We used mitochondrial sequence and nuclear minisatellite data to describe relationships among Galápagos hawk populations and their colonization history. We sampled 10 populations (encompassing the entire current species range of nine islands and one extirpated population), as well as the Galápagos hawk’s closest mainland relative, the Swainson’s hawk (B. swainsoni). There was little sequence divergence between Galápagos and Swainson’s hawks (only 0.42% over almost 3 kb of data), indicating that the hawks colonized Galápagos very recently, likely less than 300,000 years ago, making them the most recent arrivals of the studied taxa. There were only seven, closely related Galápagos hawk haplotypes, with most populations being monomorphic. The mitochondrial and minisatellite data together indicated a general pattern of rapid population expansion followed by genetic isolation of hawk breeding populations. The recent arrival, genetic isolation, and phenotypic diVerentiation among populations suggest that the Galápagos hawk, a rather new species itself, is in the earliest stages of further divergence.Buteo galapagoensis) are one of the most inbred bird species in the world, living in small, isolated island populations. We used mitochondrial sequence and nuclear minisatellite data to describe relationships among Galápagos hawk populations and their colonization history. We sampled 10 populations (encompassing the entire current species range of nine islands and one extirpated population), as well as the Galápagos hawk’s closest mainland relative, the Swainson’s hawk (B. swainsoni). There was little sequence divergence between Galápagos and Swainson’s hawks (only 0.42% over almost 3 kb of data), indicating that the hawks colonized Galápagos very recently, likely less than 300,000 years ago, making them the most recent arrivals of the studied taxa. There were only seven, closely related Galápagos hawk haplotypes, with most populations being monomorphic. The mitochondrial and minisatellite data together indicated a general pattern of rapid population expansion followed by genetic isolation of hawk breeding populations. The recent arrival, genetic isolation, and phenotypic diVerentiation among populations suggest that the Galápagos hawk, a rather new species itself, is in the earliest stages of further divergence.B. swainsoni). There was little sequence divergence between Galápagos and Swainson’s hawks (only 0.42% over almost 3 kb of data), indicating that the hawks colonized Galápagos very recently, likely less than 300,000 years ago, making them the most recent arrivals of the studied taxa. There were only seven, closely related Galápagos hawk haplotypes, with most populations being monomorphic. The mitochondrial and minisatellite data together indicated a general pattern of rapid population expansion followed by genetic isolation of hawk breeding populations. The recent arrival, genetic isolation, and phenotypic diVerentiation among populations suggest that the Galápagos hawk, a rather new species itself, is in the earliest stages of further divergence.Verentiation among populations suggest that the Galápagos hawk, a rather new species itself, is in the earliest stages of further divergence.