Assessing temperature-related changes in introgression of hybridizing species across time and space
Grants/Fellowships in support:
2009. National Science Foundation
Project Overview:
At the furthest reaches of their geographic ranges, many species breed with closely-related taxa and form hybrids. Increases in gene flow across the boundaries where hybrids form may erase the identity of the two species if their gene pools blend together (Arnold 1997). In other cases, gene flow across a hybrid zone may steadily decrease due to selection against hybrids (Ae 1995, Davies et al. 1997, Sperling 2003; Coyne and Orr 2004). Finally, new species may develop if hybrids become reproductively isolated from parental forms (Schwarz et al. 2005, 2007; Scriber and Ording 2005; Gompert et al. 2006; Mavarez et al. 2006; Scriber et al. 2008). In all cases, changes in gene flow across a hybrid zone will have large implications for the maintenance of genetic diversity.
To fill gaps in our knowledge regarding climate change and its effects on hybridization, we conducted a comparative analysis across several geographic regions where two butterflies co-occur and interbreed. Specifically, we quantified how recent climate warming and thermal factors impacted the geographic and thermal distribution of species diagnostic traits related to Papilio glaucus (Lepidoptera: Papilionidae) at the species’ northern edge and P. canadensis traits at the species’ southern edge.
Activities Conducted:
Overall study design and implementation
Field campaign management and implementation:
Data collection, management, and analysis:
2009. National Science Foundation
Project Overview:
At the furthest reaches of their geographic ranges, many species breed with closely-related taxa and form hybrids. Increases in gene flow across the boundaries where hybrids form may erase the identity of the two species if their gene pools blend together (Arnold 1997). In other cases, gene flow across a hybrid zone may steadily decrease due to selection against hybrids (Ae 1995, Davies et al. 1997, Sperling 2003; Coyne and Orr 2004). Finally, new species may develop if hybrids become reproductively isolated from parental forms (Schwarz et al. 2005, 2007; Scriber and Ording 2005; Gompert et al. 2006; Mavarez et al. 2006; Scriber et al. 2008). In all cases, changes in gene flow across a hybrid zone will have large implications for the maintenance of genetic diversity.
To fill gaps in our knowledge regarding climate change and its effects on hybridization, we conducted a comparative analysis across several geographic regions where two butterflies co-occur and interbreed. Specifically, we quantified how recent climate warming and thermal factors impacted the geographic and thermal distribution of species diagnostic traits related to Papilio glaucus (Lepidoptera: Papilionidae) at the species’ northern edge and P. canadensis traits at the species’ southern edge.
Activities Conducted:
Overall study design and implementation
Field campaign management and implementation:
- Collection of specimens across a large latitudinal transect staying on the road for weeks at a time
- Field assistant hiring and management
- Permit attainment and land owner coordination
- Climate monitoring grid design, deployment, and maintenance
Data collection, management, and analysis:
- Curation, photographic documentation, database design of specimens
- Morphometric analysis of a suite of diagnostic morphological traits to assess potential divergence between
- Environmental Niche Modeling of P. glaucus and P. canadensis
- Implementation of multiple ENM platforms, algorithms, and statistical packages to describe climatic niches for each species.
- DNA extraction, isolation, and amplification from leg samples for SNP genotyping (COI)
