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Abstract Forests play a crucial role providing ecosystem services to humans, yet many aspects of forest dynamics remain unknown. One key area is how climate change might impact reproduction of tree species. While most studies have focused on predicting tree growth, understanding how reproduction may change will be vital to forecasting future forest communities. Of particular interest is the relationship between annual growth and reproductive output, which has often been hypothesized as a trade‐off between allocating resources to growth or to reproduction. Two proposed pathways of this trade‐off, resource accumulation, that is, storage of resources over time, and resource allocation, that is, same year allocation of resources to reproduction, have been widely explored in relation to masting events. It has also been proposed that there is no internal trade‐off between the two functions, but rather there exists one or more climate variables that are intrinsically linked to both, that is, the weather hypothesis. In this study, we use 15 years of dendrochronological data and seed rain collections from forest stands at two latitudes to determine whether one or more of these strategies are taking place in two commonly occurring tree species: red maple,Acer rubrum; and sugar maple,Acer saccharum. We found evidence of a trade‐off in both species. We also found a combination of strategies was the norm, and there appeared to be evidence to also support the weather hypothesis. However, in both species, the strategy which dictated the trade‐off switched between the northern and southern regions, indicating a degree of plasticity that could be beneficial under changing environmental conditions. By identifying the ways in which growth and reproduction are connected and how these connections vary between different populations, we can gain insights into how trees allocate resources in response to changing conditions. 

Abstract Environmental adaptation and species divergence often involve suites of co‐evolving traits. Pigmentation in insects presents a variable, adaptive, and well‐characterized class of phenotypes for which correlations with multiple other traits have been demonstrated. InDrosophila, the pigmentation genesebonyandtanhave pleiotropic effects on flies' response to light, creating the potential for correlated evolution of pigmentation and vision. Here, we investigate differences in light preference within and between two sister species,Drosophila americanaandD. novamexicana, which differ in pigmentation in part because of evolution atebonyandtanand occupy environments that differ in many variables including solar radiation. We hypothesized that lighter pigmentation would be correlated with a greater preference for environmental light and tested this hypothesis using a habitat choice experiment. In a first set of experiments, using males ofD. novamexicanaline N14 andD. americanaline A00, the light‐bodiedD. novamexicanawas found slightly but significantly more often thanD. americanain the light habitat. A second experiment, which included additional lines and females as well as males, failed to find any significant difference betweenD. novamexicana‐N14 andD. americana‐A00. Additionally, the other dark line ofD. americana(A04) was found in the light habitat more often than the light‐bodiedD. novamexicana‐N14, in contrast to our predictions. However, the lightest line ofD. americana, A01, was found substantially and significantly more often in the light habitat than the two darker lines ofD. americana, thus providing partial support for our hypothesis. Finally, across all four lines, females were found more often in the light habitat than their more darkly pigmented male counterparts. Additional replication is needed to corroborate these findings and evaluate conflicting results, with the consistent effect of sex within and between species providing an especially intriguing avenue for further research.