Effect of spatial and temporal urban isolation on the genetic diversity, acoustic variation, and morphological characteristics of an urban survivor bird species

Urbanization alters ecosystems, fragmenting natural habitats, and hence, increasing isolation between populations. Therefore, a reduction in gene flow among isolated populations is expected with greater distance and time since fragmentation. Changes in the structure, density, or community composition in the remaining habitats often result in species‘ modifications of vocalizations and morphological traits. However, the relationship between genetic, vocalizations and morphological divergence in urban areas over time remains poorly understood. We analyzed ten years of genetic, acoustic, and morphological data from isolated populations of the white-eared ground-sparrow. We used seven microsatellites (SSRs), recorded, and measured five acoustic traits, and measured six morphological traits, and compared them over a period of ten years. We found an increase in inbreeding, increase in song duration, number of elements, and frequency of maximum amplitude, but a reduction in female body size and changes in male beak. However, we only identified a significant correlation between genetic diversity and the acoustic characteristics of song.