Abstract
Variation in bill, tarsus and wing length in all Galapagos populations [Nesomimus] and the closet mainland (lowland Ecuador) [Mimus] population of mockingbirds was examined with canonical variates analysis. Birds on the large, high islands are similar morphologically to those on the mainland. Populations most dissimilar to the Eucadorean one are those on Espanola, Gardner-near-Espanola, and Santa Fe. Within the Archipelago, 4 southern islands (Garnder-near-Santa Maria, Champion, Espanola, Garder-near-Espanola) have the most distinctive populations. Mockingbirds on small, low islands show varying degrees of morphological divergence from those on the large, high islands. Possible evolution of the Galapagos populations is discussed in terms of genetic bottlenecks on small islands, and gene flow among populations, depending on an island''s position in relation to prevailing winds.