DOI: 10.5061/dryad.7k824
title: Data from: Seasonal polyphenism in wing coloration affects species recognition in rubyspot damselflies (Hetaerina spp.)

description: Understanding how phenotypic plasticity evolves and in turn affects the
 course of evolution is a major challenge in modern biology. By definition,
 biological species are reproductively isolated, but many animals fail to
 distinguish between conspecifics and closely related heterospecifics. In
 some cases, phenotypic plasticity may interfere with species recognition.
 Here, we document a seasonal polyphenism in the degree of dark wing
 pigmentation in smoky rubyspot damselflies (Hetaerina titia) – a shift so
 pronounced that it led early researchers to classify different forms of H.
 titia as separate species. We further show how the seasonal colour shift
 impacts species recognition with the sympatric congener Hetaerina occisa.
 Interspecific aggression (territorial fights) and reproductive
 interference (mating attempts) are much more frequent early in the year,
 when H. titia more closely resembles H. occisa, compared to later in the
 year when the dark phase of H. titia predominates. Using wing colour
 manipulations of tethered damselflies, we show that the seasonal changes
 in interspecific interactions are caused not only by the seasonal colour
 shift but also by shifts in discriminatory behaviour in both species. We
 also experimentally tested and rejected the hypothesis that learning
 underlies the behavioural shifts in H. occisa. An alternative hypothesis,
 which remains to be tested, is that the seasonal polyphenism in H. titia
 wing coloration has resulted in the evolution of a corresponding seasonal
 polyphenism in species recognition in H. occisa. This study illustrates
 one of the many possible ways that plasticity in species recognition cues
 may influence the evolution of interspecific interactions.
description: data_file_1photographic measures of wing lightness for females at Castroville in 2012 & 2013 (date=Julien date)data_file_2photographic measures of wing lightness for females at La Palma in 2011 & 2012 (date=Julien date)data_file_3spectral measures of the lightness (tot.int) of female wings in the early (pa1) and late (pa2) seasondata_file_4photographic measures of the proportion of male wings with black pigment used for analyses presented in Fig 1.data_file_5data from male tethering experiments for H. occisa territory holders (in 2012 includes whether transect is experimental ("U") or control ("L"))data_file_6data from male tethering experiments for H. titia territory holdersdata_file_7data from conspecific/heterospecific female tethering tests (terrSP=='o' for H. occisa and 't' for H. titia) in the early ('E') and late ('L') seasons (treatment==female species)data_file_8data from wing-darkening female tethering tests (terrSP=='o' for H. occisa and 't' for H. titia) in the early ('E') and late ('L') seasons (treatment==female treatment)data_file_9data from female tethering experiments conducted during H. titia removal experiment (transect=='upper' for experimental transect and 'lower' for control transect; treatment==female treatment: 'occ' for unmanipulated H. occisa female, 'dw' H. occisa female with experimentally darkened wings, 'tit' for H. titia female)data_file_10data from clasper removal experiment (fem_treatment==female treatment; 'occ' for unmanipulated H. occisa female, 'dw' H. occisa female with experimentally darkened wings)