Hierarchical comparative analysis of genetic and genitalic geographical structure: testing patterns of male and female genital evolution in the scarab beetle Phyllophaga hirticula (Coleoptera: Scarabaeidae)

Abstract

It is generally accepted that genitalia are among the fastest evolving characters in insects and that selection on these structures may increase speciation rates in groups with polygamous mating systems. If selection is causing genitalic divergence between or among populations of a species, one prediction is that geographical structure of genitalic morphology would be in place before genetic structure of a rapidly evolving neutral marker. The current study tests this hypothesis in the geographically widespread scarab beetle Phyllophaga hirticula by evaluating whether standing variation in male and female genitalia is more or less geographically structured than a mitochondrial genetic marker. Geographical structure of mitochondrial (mt)DNA and male and female genitalic shape were analysed using analysis of variance, multivariate analysis of variance, Mantel tests, and tests of spatial autocorrelation. The results show that, although female genitalia are more geographically structured than mtDNA, male genitalia are not. This pattern suggests that selection on female genitalic variation may be causing divergence of these structures among populations.

DELIMITING SPECIES USING MULTILOCUS DATA: DIAGNOSING CRYPTIC DIVERSITY IN THE SOUTHERN CAVEFISH,TYPHLICHTHYS SUBTERRANEUS(TELEOSTEI: AMBLYOPSIDAE)

“…The null hypothesis that the degree of exclusive ancestry is observed by chance alone (i.e., no divergence) was evaluated by estimating a P value using 10,000 permutations. Uneven sample sizes among groups can shift P values downward for smaller group sizes; therefore, significance was inferred at P < 0.01 (Polihronakis 2009; Gazis et al 2011).…”

Molecular evolution and phylogenetics of rodent malaria parasites

“…A p-value was then computed as the probability of randomly obtaining gsi T values that are equal to or greater than the observed gsi T value [16]. As our dataset is unbalanced and it is known that uneven sample sizes can lead to an underestimation of the p-values for small group sizes, we assessed significance at 0.001 [12,16,45,46]. …”

Unraveling Cryptic Diversity in the Indo-West Pacific Gastropod GenusLunella(Turbinidae) using Elliptic Fourier Analysis*

“…EFA in combination with quantitative genetic analysis has also been shown to detect evidence of selection acting on biological shapes (e.g. Polihronakis 2008). Outline analyses are particularly useful in taxa where homology of landmarks is uncertain (Van Bocxlaer and Schultheiß 2010).…”