Abstract
Mating behavior divergence can make significant contributions to reproductive isolation and speciation in various biogeographic contexts. However, whether the genetic architecture underlying mating behavior divergence is related to the biogeographic history and the tempo and mode of speciation remains poorly understood. Here, we use quantitative trait locus (QTL) mapping to infer the number, distribution, and effect size of mating song rhythm variations in the crickets Laupala eukolea and Laupala cerasina, which occur on different islands (Maui and Hawaii). We then compare these results with a similar study of an independently evolving species pair that diverged within the same island. Finally, we annotate the L. cerasina transcriptome and test whether the QTL fall in functionally enriched genomic regions. We document a polygenic architecture behind the song rhythm divergence in the inter-island species pair that is remarkably similar to that previously found for an intra-island species pair in the same genus. Importantly, the QTL regions were significantly enriched for potential homologs of the genes involved in pathways that may be modulating the cricket song rhythm. These clusters of loci could constrain the spatial genomic distribution of the genetic variation underlying the cricket song variation and harbor several candidate genes that merit further study.
Highlights
Behavioral divergence can produce significant reproductive barriers in animals and can be an important force driving speciation [1,2,3,4,5]
It has been argued that the type of genetic architecture, whether phenotypic change is the result of polygenic, additive alleles (Type I) or of major effect alleles with strong epistatic modifiers (Type II) [10], can be informative about the tempo and mode of speciation [11,12]
This study presents rare comparative insights into the polygenic genetic architecture associated with sexual trait divergence during speciation in different biogeographic contexts
Summary
Behavioral divergence can produce significant reproductive barriers in animals and can be an important force driving speciation [1,2,3,4,5]. We can gain insight into the genetic causes and consequences of divergence in important speciation forces and phenotypes. The traits involved in behavioral isolation are often quantitative, and the divergence in these traits is usually caused by many changes of small effect [3,6]. It has been argued that the type of genetic architecture, whether phenotypic change is the result of polygenic, additive alleles (Type I) or of major effect alleles with strong epistatic modifiers (Type II) [10], can be informative about the tempo and mode of speciation [11,12]. It has been suggested that Type II architectures may be lynch pins in the radiations involving founder effects [11], Genes 2018, 9, 346; doi:10.3390/genes9070346 www.mdpi.com/journal/genes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
