Does breeding season variation affect evolution of a sexual signaling trait in a tropical lizard clade?. Issue 8 (17th March 2020)

• Record Type: Journal Article
• Authors: Gray, Levi N.; Barley, Anthony J.; Hillis, David M.; Pavón‐Vázquez, Carlos J.; Poe, Steven; White, Brittney A.
• Is Part Of: Ecology and evolution. Volume 10:Issue 8(2020)
• Page Start: 3738
• Page End: 3746
• Publication Date: 2020-03-17
• Subjects: Anolis -- dewlap -- sensory drive -- sexual selection -- signaling trait evolution -- species recognition; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.6167
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: Sexually selected traits can be expected to increase in importance when the period of sexual behavior is constrained, such as in seasonally restricted breeders. Anolis lizard male dewlaps are classic examples of multifaceted signaling traits, with demonstrated intraspecific reproductive function reflected in courtship behavior. Fitch and Hillis found a correlation between dewlap size and seasonality in mainland Anolis using traditional statistical methods and suggested that seasonally restricted breeding seasons enhanced the differentiation of this signaling trait. Here, we present two tests of the Fitch–Hillis Hypothesis using new phylogenetic and morphological data sets for 44 species of Mexican Anolis . A significant relationship between dewlap size and seasonality is evident in phylogenetically uncorrected analyses but erodes once phylogeny is accounted for. This loss of strong statistical support for a relationship between a key aspect of dewlap morphology and seasonality also occurs within a species complex ( A. sericeus group) that inhabits seasonal and aseasonal environments. Our results fail to support seasonality as a strong driver of evolution of Anolis dewlap size. We discuss the implications of our results and the difficulty of disentangling the strength of single mechanisms on trait evolution when multiple selection pressures are likely at play. Abstract : Using new data sets, we retested support for a correlation between anole dewlap size and seasonality. Our results suggest that the previously recognized pattern of larger dewlaps in highly seasonal environments, independently verified in our study, is explained by shared evolutionary history.