The roles of wing color pattern and geography in the evolution of Neotropical Preponini butterflies

Abstract

Diversification rates and evolutionary trajectories are known to be influenced by phenotypic traits and the geographic history of the landscapes that organisms inhabit. One of the most conspicuous traits in butterflies is their wing color pattern, which has been shown to be important in speciation. The evolution of many taxa in the Neotropics has also been influenced by major geological events. Using a dated, species-level molecular phylogenetic hypothesis for Preponini, a colorful Neotropical butterfly tribe, we evaluated whether diversification rates were constant or varied through time, and how they were influenced by color pattern evolution and biogeographical events. We found that Preponini originated approximately 28 million years ago and that diversification has increased through time consistent with major periods of Andean uplift. Even though some clades show evolutionarily rapid transitions in coloration, contrary to our expectations, these shifts were not correlated with shifts in diversification. Involvement in mimicry with other butterfly groups might explain the rapid changes in dorsal color patterns in this tribe, but such changes have not increased species diversification in this group. However, we found evidence for an influence of major Miocene and Pliocene geological events on the tribe's evolution. Preponini apparently originated within South America, and range evolution has since been dynamic, congruent with Andean geologic activity, closure of the Panama Isthmus, and Miocene climate variability.

Keywords: Lepidoptera phylogenetics; Neotropical biogeography; butterfly diversification; wing color pattern evolution.

Figure 1

Example Preponini species. Butterflies shown (from left to right across each row): Archaeoprepona licomedes, A. demophon, A. demophoon, A. amphimachus, A. meander, A. camilla, A. chalciope, A. priene, Mesoprepona pheridamas, Prepona dexamenus, P. laertes, P. werneri, P. gnorima, P. deiphile, P. praeneste, P. narcissus, P. aedon, P. hewitsonius, P. claudina, P. amydon. Photos by P. S. Padrón and A. Warren

Figure 2

Ancestral reconstruction of the mode RGB red channel for the Cell 1 and lineage‐through‐time plot (solid blue line). Blue dotted line denotes expectation of lineage accumulation under a pure birth process. Red, blue, and gray triangles highlight branches where a jump in color was identified for the blue, red, and total channels in Cells 1 and 2 (see text for details). Vertical color bars denote the red and blue Preponini clades. Abbreviations follow: PL: Pliocene, P: Pleistocene. Butterflies shown (from top to bottom): Prepona claudina, P. laertes, Mesoprepona pheridamas, and Archaeoprepona licomedes. Photos by P. S. Padrón

Figure 3

Biogeographical range estimates for the tribe Preponini based on the DEC model. Dotted gray lines delimit the time slices used in the stratified analysis. Upward black triangles denote periods of increased Andean uplift (Hoorn et al., 2010), downward black triangles denote periods of increased biological migration between Central and South America, and downward white triangle denotes initial faunal exchange between Central and South America at ~41 Ma (Bacon et al., 2015). Roman numerals in nodes refer to the main text. Abbreviations follow: PL: Pliocene, P: Pleistocene. Butterflies shown (from top to bottom): Archaeoprepona meander, A. chalciope, A. licomedes, A. priene, Mesoprepona pheridamas, Prepona laertes, P. werneri, P. deiphile, P. praeneste, P. narcissus, P. claudina. Photos by P. S. Padrón and EOA