population genomics reveals multiple drivers of population differentiation

Population genomics reveals multiple drivers of population differentiation in a sex-role-

reversed pipefishSarah P. Flanagan, Emily Rose, Adam G. Jones

Texas A&M UniversityEvolution 2016

@sarahpf19spflanagan.phd@gmail.com

Differences between populations: why do we care?

Variation is the substrate of evolution

What causes population differentiation?

Neutral processes: genetic drift

Natural selection: local adaptation

Geographic variation in selection

F Jones et al. (2012), Nature Mobley & AG Jones(2012), Mol Ecol

What are the relative contributions of these processes?

How do we detect these processes?

Morphology and measurable traits Genomic patterns

Hohenlohe et al. (2010), Int J Plant SciFlanagan et al. (2014), JEB

Questions of Interest

• What is the relative importance of each process?

• Do morphological patterns of differentiation match genetic patterns?

Syngnathus scovelli

Syngnathus scovelli

Flanagan et al. (2014), JEB

Syngnathus scovelli

• Expected low dispersal • Natural selection favoring

crypsis• Strong sexual selection

Collecting

Chapter 1

The approach

ddRAD-sequencing Morphological Characteristics

Analzying RAD-seq Data

• Assembled reads into clusters and identified SNPs

• Created two sets of SNPS:– Pruned (1753)– All filtered SNPs (6348)

Catchen et al. (2011, 2013)

Mantel test: p = 0.02

Neutral Population Structure

Local Adaptation Outlier Loci

H ACA ribonucleoprotein complex non-core subunit NAF1

Phenotypic differentiation

Conclusions• Neutral processes primarily drive genetic

differentiation– Although there is some evidence for local

adaptation• Phenotypic differentiation follows a different

pattern than genetic differentiation

Acknowledgements

– Adam Jones– Emily Rose– Andrew Anderson– Kim Paczolt– Clay Small– Charlyn Partridge– Nicole Ortega– Heather Masonjones– Sawyer Masonjones– David Mahlmann– Emily Kasl– Melissa Giresi– Kevin Records– Alex Saucedo– William Cresko

Migration rates

Bayenv Regions Associated with Environmental Variables GO categories