Alpha taxonomy endeavours to propose a coherent vision of existing species and, simultaneously, to individualize the natural entities useful to understand evolutionary processes. This ideal is especially difficult when available data lack congruence. Here we address the polytypic species Synallaxis rutilans (ruddy spinetail), a suboscine passerine widely distributed in the Amazon Basin and whose taxonomy could, potentially, aid our understanding of processes shaping its biodiversity. Combining genetic [genomic ultraconserved elements (UCE) and mtDNA] and morphological data, we demonstrate that while delimitation of genetic lineages and their phylogenetic relationships are strongly associated with classic Amazonian geographic barriers, such as rivers, different coloration patterns appear to be more associated with local selection processes for phenotype. Employing an evolutionary approach, whereby the species is considered a taxonomic category, rather than a nomenclatural rank, we propose to recognize five species: S. amazonica, S. caquetensis, S. dissors, S. omissa and S. rutilans. The taxonomic arrangement proposed here permits better understanding of the similarities and differences among taxa from different areas of endemism, and represents patterns of genetic and morphological diversity resulting from distinct processes acting across certain time frames. This arrangement draws attention to the importance of understanding the evolutionary processes operating in the complex and constantly changing Amazonian landscape.
Our understanding of how natural selection and demographic processes produce and maintain biological diversity remains limited. However, developments in high-throughput genomic sequencing coupled with new analytical tools and phylogenetic methods now allow detailed analyses of evolutionary patterns in genes and genomes responding to specific demographic events, ecological changes, or other selection pressures. Here, we propose that the mosquitoes in the Culex pipiens complex, which include taxa of significant medical importance, provide an exceptional system for examining the mechanisms underlying speciation and taxonomic radiation. Furthermore, these insects may shed light on the influences that historical and contemporary admixture have on taxonomic integrity. Such studies will have specific importance for mitigating the disease and nuisance burdens caused by these mosquitoes. More broadly, they could inform predictions about future evolutionary trajectories in response to changing environments and patterns of evolution in other cosmopolitan and invasive species that have developed recent associations with humans.more » « less
- NSF-PAR ID:
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Annals of the Entomological Society of America
- Medium: X Size: p. 95-104
- ["p. 95-104"]
- Sponsoring Org:
- National Science Foundation
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