Autor: |
Andrade-González VM; Colección Nacional de Aves, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, CP 04510, México.; Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Ciudad de México, CP 04510, México., Vázquez-Miranda H; Colección Nacional de Aves, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, CP 04510, México., Ornelas-García CP; Colección Nacional de Peces, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, CP 04510, México., Sosa-López JR; Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad Oaxaca (CIIDIR), Instituto Politécnico Nacional, Santa Cruz Xoxocotlán, CP 71230, México. |
Abstrakt: |
The study of ecological mechanisms influencing organisms' phenotypic variation is a central subject of evolutionary biology. In this study, we characterized morphological, plumage colour and acoustic variation in cactus wrens Campylorhynchus brunneicapillus throughout its distribution. We assessed whether Gloger's, Allen's and Bergmann's ecogeographical rules, and the acoustic adaptation hypothesis relate to geographical trait variation. We analysed specimen coloration in belly and crown plumage, beak shape and structural song characteristics. We tested whether the subspecific classification or the peninsular/mainland groups mirrored the geographical variation in phenotypes and whether ecological factors were associated with patterns of trait variation. Our results suggest that colour, beak shape and acoustic traits varied across the range, in agreement with two lineages described by genetics. The simple versions of Gloger's and Allen's rules are related to variations in colour traits and morphology. Conversely, patterns of phenotypic variation did not support Bergmann's rule. The acoustic adaptation hypothesis supported song divergence for frequency-related traits. Phenotypic variation supports the hypothesis of two taxa: C. affinis in the Baja California peninsula and C. brunneicapillus in the mainland. The ecological factors are associated with phenotypic trait adaptations, suggesting that divergence between lineages could result from ecological divergence. |