Color polymorphisms have become a major topic in evolutionary biology and substantial efforts have been devoted to the understanding of the mechanisms responsible for originating such colorful systems. Within‐morph continuous variation, on the other hand, has been neglected in most of the studies. Here, we combine spectrophotometric/visual modeling and genetic data to study the mechanisms promoting continuous variation within categorical color morphs of Podarcis muralis. Our results suggest that intra‐morph variability in the pterin‐based orange morph is greater compared to white and yellow morphs. We also show that continuous variation within the orange morph is partially discriminable by conspecifics. Genotyping results indicate that allelic variants at the BCO2 locus (responsible for deposition of yellow carotenoids) contribute to generate continuous variation in orange individuals. However, other intrinsic and/or extrinsic mechanisms, such as body size, might be involved, opening a new avenue for future research on the drivers of continuous variation within‐morphs.

Long‐term maintenance of colour polymorphisms often depends on the interplay of multiple selective forces. In the common wall lizard (Podarcis muralis), up to three pure and two mosaic ventral colour morphs co‐exist across most of its range. Available evidence suggests that colour morphs in this species are maintained through the interaction between sexual and environment‐dependent selection. In particular, colour‐assortative pairing has been recorded, suggesting some degree of assortative mating. Here, we combined reduced‐representation sequencing (ddRADseq) and fine‐scale distribution data to explore the effects of assortative pairing on the common wall lizard. Overall, our results do not support any population structure (FST = 0 and K = 1) nor a significant effect of colour morph or geographic location on genomic differentiation. Therefore, we argue that assortative pairing may not fully translate into assortative mating and genomic differentiation between colour morphs and discuss possible explanations. Nonetheless, we find potential support for an elevated population size and/or source‐sink dynamics and debate the potential contribution of other forms of selection to the maintenance of colour polymorphisms in lacertids.

Advanced paternal age has been repeatedly shown to modulate offspring quality via male-and/or female-driven processes, and there are theoretical reasons to expect that some of these effects can be sex-specific. For example, sex allocation theory predicts that, when mated with low-condition males, mothers should invest more in their daughters compared to their sons. This is because male fitness is generally more condition-dependent and more variable than female fitness, which makes it less risky to invest in female offspring. Here, we explore whether paternal age can affect the quality and quantity of offspring in a sex-specific way using Drosophila melanogaster as a model organism. In order to understand the contribution of male-driven processes on paternal age effects, we also measured the seminal vesicle size of young and older males and explored its relationship with reproductive success and offspring quality.Older males had lower competitive reproductive success, as expected, but there was no difference between the offspring sex ratio of young and older males. However, we found that paternal age caused an increase in offspring quality (i.e., offspring weight), and that this increase was more marked in daughters than sons. We discuss different male-and female-driven processes that may explain such sex-specific paternal age effects.

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