Abstract. We tested whether and how functional composition changes with succession in dry deciduous and wet evergreen forests of Mexico. We hypothesized that compositional changes during succession in dry forest were mainly determined by increasing water availability leading to community functional changes from conservative to acquisitive strategies, and in wet forest by decreasing light availability leading to changes from acquisitive to conservative strategies. Research was carried out in 15 dry secondary forest plots (5-63 years after abandonment) and 17 wet secondary forest plots (,1-25 years after abandonment). Community-level functional traits were represented by community-weighted means based on 11 functional traits measured on 132 species. Successional changes in functional composition are more marked in dry forest than in wet forest and largely characterized by different traits. During dry forest succession, conservative traits related to drought tolerance and drought avoidance decreased, as predicted. Unexpectedly acquisitive leaf traits also decreased, whereas seed size and dependence on biotic dispersal increased. In wet forest succession, functional composition changed from acquisitive to conservative leaf traits, suggesting light availability as the main driver of changes. Distinct suites of traits shape functional composition changes in dry and wet forest succession, responding to different environmental filters.

Summary Successional gradients are ubiquitous in nature, yet few studies have systematically examined the evolutionary origins of taxa that specialize at different successional stages. Here we quantify successional habitat specialization in Neotropical forest trees and evaluate its evolutionary lability along a precipitation gradient. Theoretically, successional habitat specialization should be more evolutionarily conserved in wet forests than in dry forests due to more extreme microenvironmental differentiation between early and late‐successional stages in wet forest. We applied a robust multinomial classification model to samples of primary and secondary forest trees from 14 Neotropical lowland forest sites spanning a precipitation gradient from 788 to 4000 mm annual rainfall, identifying species that are old‐growth specialists and secondary forest specialists in each site. We constructed phylogenies for the classified taxa at each site and for the entire set of classified taxa and tested whether successional habitat specialization is phylogenetically conserved. We further investigated differences in the functional traits of species specializing in secondary vs. old‐growth forest along the precipitation gradient, expecting different trait associations with secondary forest specialists in wet vs. dry forests since water availability is more limiting in dry forests and light availability more limiting in wet forests. Successional habitat specialization is non‐randomly distributed in the angiosperm phylogeny, with a tendency towards phylogenetic conservatism overall and a trend towards stronger conservatism in wet forests than in dry forests. However, the specialists come from all the major branches of the angiosperm phylogeny, and very few functional traits showed any consistent relationships with successional habitat specialization in either wet or dry forests. Synthesis. The niche conservatism evident in the habitat specialization of Neotropical trees suggests a role for radiation into different successional habitats in the evolution of species‐rich genera, though the diversity of functional traits that lead to success in different successional habitats complicates analyses at the community scale. Examining the distribution of particular lineages with respect to successional gradients may provide more insight into the role of successional habitat specialization in the evolution of species‐rich taxa.

Stakeholder groups are not homogeneous across individuals and through time, especially in relation to the importance of ecosystem services. However, the approaches commonly used to characterize the average importance and values of stakeholder groups overlook the heterogeneity in the individual priorities. This heterogeneity is particularly relevant for smallholders, who play a key role in ecosystem management but are more vulnerable to globalization than owners of large plots. We analyzed the priorities differentially assigned to ecosystem services and the reasons associated with the importance attributed to those services by individual cattle ranchers on the Pacific Coast of Mexico. We interviewed 27 cattle ranchers from neighboring rural communities. The services perceived by each rancher were identified from selected regional photographs. These services were then arranged in order of importance by interviewees, who were asked to provide the reasons for their choices. We used multivariate methods to examine the relationship between priorities for services and the livelihood of the individual. Interpretative qualitative methods elicited the reasons associated with the relative importance of the prioritized services. We identified 54 different services. Overall, individuals prioritized provisioning services directly related to their ranching activity. Individuals with the highest level of education and greatest diversity of productive activities (e.g., farmer, mason, merchant) also prioritized cultural services associated with ecotourism potential. The reasons associated with the importance attributed to the prioritized services varied widely among individuals. The list of ecosystem services perceived was context-specific, strongly influenced by the salient characteristics of the ecosystem and of the ranching way of life. A generational change in livelihoods has affected priorities. The reasons behind the importance of the prioritized services were diverse among individuals. By revealing the heterogeneity among individuals, we emphasize the need to make flexible policies that integrate diverse values and contexts to accomplish smallholder inclusivity.

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In recent years, environmental values have become increasingly important for understanding human–environment relationships and transitions towards sustainability. Pluralistic valuation seeks to account for values associated with the diversity of human–nature relationships. Relational values (RV) have been proposed as a concept that can aid in plural valuation. RV concern the relationships that people have with their environments. Most RV studies focus on ‘desirable’ or ‘beneficial’ RV that contribute to pro‐environmental actions and sustainable outcomes. We argue that RV could be expanded to understand values that may be less environmentally beneficial. We focus our analysis on RV that exist in ‘simplified’ landscapes. Drawing on our research on cattle‐based livelihoods in Latin America, we highlight potential approaches to the study of RV in such simplified landscapes. We then build on the examples to examine themes and principles of RV with the aim of stimulating discussion about how the concept might be refined and expanded to study a broader range of human–environment relationships. Overall, our aim is to contribute to plural valuation and offer preliminary suggestions for how RV might expand to capture the complexity of values, from those that are desirable to those which contribute to environmental degradation. Expanding the scope of RV research and the depth of the RV concept can help to understand the challenges to sustainability and contribute to the shared goals of sustainability that motivate values research. Read the free Plain Language Summary for this article on the Journal blog.