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ABSTRACT Synanthropic species live in close association with, or benefit from, humans. Despite their potential impacts to human health, little is known about the mechanisms driving synanthropic life‐history evolution, evolutionary forces shaping diet among synanthropes, or how these combined factors affect population dynamics and/or speciation. The Tineidae moth family contains several synanthropic species, including the globally distributed pest speciesTineola bissellellia, that contribute to the ~$1 billion worth of damage caused annually by keratinophagous synanthropes. Synanthropy among Tineidae is associated with a wide range of dietary strategies. While most tineids display obligate detritivory, synanthropic species are typically either facultatively or obligately keratinophagous. However, little is known about evolutionary relationships within Tineidae, hampering efforts to investigate the relationship between synanthropy and diet evolution. Here, to address this challenge, we extracted DNA from 39 tineid samples and two outgroups, including the closely relatedTineolaandTineagenera, and generated genome‐wide sequence data for thousands of ultraconserved elements (UCEs). Our phylogenetic analyses, using a concatenated maximum‐likelihood‐based approach, resulted in a well‐supported, fully resolved phylogeny that demonstrates synanthropy has evolved multiple times and is consistently associated with facultative and obligate keratinophagy. Bayesian divergence time estimation indicates Cretaceous divergence among deep‐branching tineid lineages, an ancestral origin of facultative keratinophagy, and a recent origin of the most economically important synanthropic pest,Tineola bissellellia,from within genusTinea. Taken together, our results suggest that a shift to facultative keratinophagy was a key evolutionary innovation that has fuelled the repeated evolution of synanthropic life histories among this deep‐diverging moth family. 

Abstract Color vision is thought to play a key role in the evolution of animal coloration, while achromatic vision is rarely considered as a mechanism for species recognition. Here we test the hypothesis that brightness vision rather than color vision helpsAdelpha fessoniabutterflies identify potential mates while their co-mimetic wing coloration is indiscriminable to avian predators. We examine the trichromatic visual system ofA. fessoniaand characterize its photoreceptors using RNA-seq, eyeshine, epi-microspectrophotometry, and optophysiology. We model the discriminability of its wing color patches in relation to those of its co-mimic,A. basiloides, throughA. fessoniaand avian eyes. Visual modeling suggests that neitherA. fessonianor avian predators can readily distinguish the co-mimics’ coloration using chromatic or achromatic vision under natural conditions. These results suggest that mimetic colors are well-matched to visual systems to maintain mimicry, and that mate avoidance between these two look-alike species relies on other cues. 

Batesian mimicry occurs when palatable mimics gain protection from predators by evolving a phenotypic resemblance to an aposematic model species. While common in nature, the mechanisms maintaining mimicry are not fully understood. Patterns of temporal synchrony (i.e. temporal co-occurrence) and model first occurrence have been observed in several mimicry systems, but the hypothesis that predator foraging decisions can drive the evolution of prey phenology has not been experimentally tested. Here, using phenotypically accurate butterfly replicas, we measured predation rates on the chemically defended model speciesBattus philenorand its imperfect Batesian mimicLimenitis arthemis astyanaxunder four different phenological conditions to understand the importance of temporal synchrony and model first occurrence in mimicry complexes. We predicted that protection for mimics increases when predators learn to avoid the models' aposematic signal right before encountering the mimic, and that learned avoidance breaks down over time in the model’s absence. Surprisingly, we found that asynchronous model first occurrence, even on short time scales, did not provide increased protection for mimics. Mimics were only protected under conditions of temporal synchrony, suggesting that predators rely on current information, not previously learned information, when making foraging decisions.