Urban ecosystems are rapidly expanding throughout the world, but how urban growth affects the evolutionary ecology of species living in urban areas remains largely unknown. Urban ecology has advanced our understanding of how the development of cities and towns change environmental conditions and alter ecological processes and patterns. However, despite decades of research in urban ecology, the extent to which urbanization influences evolutionary and eco‐evolutionary change has received little attention. The nascent field of urban evolutionary ecology seeks to understand how urbanization affects the evolution of populations, and how those evolutionary changes in turn influence the ecological dynamics of populations, communities, and ecosystems. Following a brief history of this emerging field, this Perspective article provides a research agenda and roadmap for future research aimed at advancing our understanding of the interplay between ecology and evolution of urban‐dwelling organisms. We identify six key questions that, if addressed, would significantly increase our understanding of how urbanization influences evolutionary processes. These questions consider how urbanization affects nonadaptive evolution, natural selection, and convergent evolution, in addition to the role of urban environmental heterogeneity on species evolution, and the roles of phenotypic plasticity versus adaptation on species’ abundance in cities. Our final question examines the impact of urbanization on evolutionary diversification. For each of these six questions, we suggest avenues for future research that will help advance the field of urban evolutionary ecology. Lastly, we highlight the importance of integrating urban evolutionary ecology into urban planning, conservation practice, pest management, and public engagement.

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The evolutionary transition from outcross-fertilization to self-fertilization is one of the most common in angiosperms and is often associated with a parallel shift in floral morphological and developmental traits, such as reduced flower size and pollen to ovule ratios, known as the ‘selfing syndrome’. How these convergent phenotypes arise, the extent to which they are shaped by selection, and the nature of their underlying genetic basis are unsettled questions in evolutionary biology. The genus Collinsia (Plantaginaceae) includes seven independent transitions from outcrossing or mixed mating to high selfing rates accompanied by selfing syndrome traits. Accordingly, Collinsia represents an ideal system for investigating this parallelism, but requires genomic resource development. We present a high quality de novo genome assembly for the highly selfing species C. rattanii. To begin addressing the basis of selfing syndrome developmental shifts, we evaluate and contrast patterns of gene expression from floral transcriptomes across three stages of bud development for C. rattanii and its outcrossing sister species C. linearis. Relative to C. linearis, total gene expression is less variable among individuals and bud stages in C. rattanii. In addition, there is a common pattern among differentially expressed genes: lower expression levels that are more constant across bud development in C. rattanii relative to C. linearis. Transcriptional regulation of enzymes involved in pollen formation specifically in early bud development may influence floral traits that distinguish selfing and outcrossing Collinsia species through pleiotropic functions. Future work will include additional Collinsia outcrossing-selfing species pairs to identify genomic signatures of parallel evolution.

Questions The study of organisms living in extreme environments has shaped our knowledge of the deterministic and stochastic factors that contribute to community assembly. With hardscape habitats (HH), humans have created a novel land‐cover type that is physically analogous to extreme terrestrial environments such as deserts, barrens, and rocky outcrops and may harbor rare or specialist species and communities. We addressed the following questions: (a) which plant species inhabit hardscapes; (b) do hardscapes serve as a refuge for rare or specialist species; (c) how taxonomically similar are hardscape plant communities to one another and the regional species pool; (d) is phylogenetic diversity of hardscape communities different from that of the regional species pool; and (e) which functional traits and life history strategies are filtered for or against in hardscape plant communities? Location and Methods We surveyed the vascular plant communities of 17 asphalt parking lots in New Jersey, USA, to use as a focal hardscape habitat for this study. Results Parking‐lot plant communities contained 119 vascular plant taxa out of the 2,199 regional species and had a lower beta and phylogenetic diversity than the regional species pool. The parking‐lot flora had significantly higher frequencies of annuals, biennials, C4 plants, ruderal strategists, non‐natives, herbaceous plants, self‐compatible species, and species from the Caryophyllales, Asterales, Ulmaceae, and Plantaginaceae clades compared to the regional pool and contained no New Jersey threatened or endangered species. Conclusions Hardscape habitats may be similar to naturally occurring, extreme terrestrial environments in that they impose stringent filters on ecological communities leading to increased proportions of short‐lived and C4 plant species compared to the regional pool. Nevertheless, hardscapes are unlikely to serve as biodiversity refuges in the Northeastern USA as they create novel abiotic conditions that may be hostile to many native, rare, and specialist species.

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