Population genetic structure and vocal dialects in an amazon parrot

Abstract

The relationship between cultural and genetic evolution was examined in the yellow-naped amazon Amazona auropalliata. This species has previously been shown to have regional dialects de¢ned by large shifts in the acoustic structure of its learned contact call. Mitochondrial DNA sequence variation from a 680 base pair segment of the ¢rst domain of the control region was assayed in 41 samples collected from two neighbouring dialects in Costa Rica. The relationship of genetic variation to vocal variation was examined using haplotype analysis, genetic distance analysis, a maximum-likelihood estimator of migration rates and phylogenetic reconstructions. All analyses indicated a high degree of gene £ow and, thus, individual dispersal across dialect boundaries. Calls sampled from sound libraries suggested that temporally stable contact call dialects occur throughout the range of the yellow-naped amazon, while the presence of similar dialects in the sister species Amazona ochrocephala suggests that the propensity to form dialects is ancestral in this clade. These results indicate that genes and culture are not closely associated in the yellow-naped amazon. Rather, they suggest that regional diversity in vocalizations is maintained by selective pressures that promote social learning and allow individual repertoires to conform to local call types.

Bird song, ecology and speciation

“…While some studies have found concordance in geographical patterns of acoustic and genetic variation (white-crowned sparrow: Baker (1982), Baker et al (1982Baker et al ( , 1984), many others do not. In a variety of studies, dialects do not correspond with discrete genetic boundaries (rufous-collared sparrow, Zonotrichia capensis: Handford & Nottebohm (1976), Lougheed & Handford (1992), ; white-crowned sparrow: Zink & Barrowclough (1984), Hafner & Petersen (1985); brown-headed cowbird, Molothrus ater : Fleischer & Rothstein (1988); indigo bunting, Passerina cyanea: Payne & Westneat (1988); yellow-naped amazon, Amazona auropalliata: Wright & Wilkinson (2001)). In addition, one study found a correlation between song and genetic variation for some populations, but not for others (swamp sparrow;Balaban (1988a)).…”

Marine Mammal Acoustic Monitoring and Habitat Investigation, Southern California Channel Island Region

“…In birds, the relationship between song dialects and population structure show conflicting results (reviewed in Catchpole andSlater, 1995 andSlabbekoorn andSmith, 2002). Some studies find little evidence of genetic differentiation (Fleischer et al, 1988;Wright and Wilkinson, 2001) while others show a strong correlation between dialects and genetic variation (MacDougall-Shackleton and MacDougall-Shackleton, 2001) sometimes indicating higher level divergence (Irwin et al, 2001b). Several factors contribute to these differences, including the social function and the timing of vocal learning relative to dispersal (Wright and Wilkinson, 2001).…”

A Draft Sequence of the Puerto Rican Parrot Genome (Amazona vittata) – a Genome Project funded by a Local Community Effort

“…Gentetic variation has been previously suspected to be associated with several adaptive traits other Amazona parrots 14 . Newly sequenced genomes will be aligned to the reference genome to discover and describe genetic variation across the chromosomes.…”