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Global change is expected to drive short‐term evolution of natural populations. However, it remains unclear whether different populations are changing in unison. Here, we study contemporary evolution of growth‐related and reproductive traits of three populations of Cyanus segetum facing warming and pollinator decline across a latitudinal gradient in France. We resurrected stored seeds sampled up to 24 years apart from northern, central‐western, and southern populations and conducted an in situ common‐garden experiment. To disentangle neutral from selection‐driven differentiation, we calculated neutral genetic differentiation (FST) and quantitative trait differentiation (QST) between temporal samples. We found that phenotypic evolution was divergent across populations exhibiting different trends for rosette size, date of flowering, and capitula size. By measuring seed set as a proxy of fitness, we showed that samples with larger mean capitula size outperformed samples with smaller mean capitula size in the western and southern populations. Regression of traits on seed set showed that flowering date and capitula size are the primary determinants of fitness, and QST‐FST comparisons indicated that natural selection has likely contributed to the shifts in flowering phenology and rosette size. These findings outline the potential for rescue of natural populations through contemporary evolution and emphasize the complex interplay between spatial and temporal variation in species' responses to global change. [ABSTRACT FROM AUTHOR]

The decline of pollinators has been demonstrated scientifically and this phenomenon is widely recognized by both the general public and by stakeholders. Since pollinators face different threats that are all linked to human activities, there is a unique and unprecedented responsibility for people to conserve pollinators, requiring political action to counter the substantial worldwide risk of pollinator loss. As our perception of the situation is rapidly changing, as a result of the steady accumulation of international and national reports as well as new scientific findings, we propose here to provide an updated overview of pollinator conservation globally. We present the key messages and the proposed solutions found in international reports and assessments, how European countries have interpreted these solutions proposed in the context of existing international frameworks. Next, we analyze how scientific research is addressing the issue of pollinator conservation through different international, European and national programs. The analysis of the keywords used in published scientific articles also allows us to characterize how the scientific community has engaged with this issue over time. Finally, we focus on how France and Belgium have reacted to the observed decline of pollinators, and examine their national interpretations, conservation actions and research contributions. • We propose here to provide an updated overview of pollinator conservation globally. • We investigated how European countries have interpreted the existing international frameworks. • We analyzed the keywords used in published scientific articles on pollinators and pollination. • We focus on how France and Belgium have reacted to the observed decline of pollinators. • We examine their national interpretations, conservation actions and research contributions. [ABSTRACT FROM AUTHOR]

Global change is expected to impose new selection pressures on natural populations. Phenotypic responses, such as earlier phenology in response to climate warming, have been repeatedly observed in the field. The recent pollinator decline is also expected to change selection on reproductive traits in flowering plants. However, it remains unclear whether short-term adaptation of plant reproductive strategies occurs in response to global change. In this study, we report the evolution of some important reproductive traits of the annual self-incompatible weed Centaurea cyanus. In a common garden experiment, we germinated stored seeds, sampled 18 years apart from the same location, in a region where warmer springs and indices of pollinator decline have been reported. Compared to the ancestral population (1992), our results showed that plants of the descendant population (2010) flowered earlier and also produced larger capitula with longer receptivity and a larger floral display. QST -FST comparisons indicated that natural selection has likely contributed to the evolution of some of the traits investigated. Lower FST within temporal samples than among spatial samples further suggests a limited role of gene flow from neighbouring populations. We therefore propose that trait shifts could partly be due to adaptation to global change., (© 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.)