Ontogenetic shifts in plants are ubiquitous, but their ecological and evolutionary significance remain largely unknown. Juveniles have few opportunities to accumulate sufficient biomass to withstand damage, whereas adults allocate resources to reproduction. Thus, age‐specific environmental filters are expected to drive selection towards specific resource‐investment strategies for each developmental stage. We tested whether species exhibited strategies that favour faster rates of biomass accumulation during early developmental stages to cope with vulnerability, shifting towards habitat‐dependent strategies to optimise resource acquisition and use later on. We also hypothesised that juveniles exhibit greater intraspecific variability of strategies than adults, as a result of continuous filtering of traits throughout the plant’s development towards adulthood. We measured key leaf traits—leaf area (LA), leaf dry matter content (LDMC) and specific leaf area (SLA)—and calculated scores for competitor (C), stress‐tolerator (S), ruderal (R) strategies of the CSR system for juveniles of 54 species and conspecific adults of 27 species naturally occurring either in unproductive (grassland) or productive (forest) habitats. Juveniles exhibited higher SLA and LA and lower LDMC, and thus a more R‐strategy in both habitats when compared with adults, but were not necessarily “R” in absolute terms. We also found smaller intraspecific variation for the R‐strategy in adults compared with juveniles in both habitats, whereas the variation of the other strategies was habitat dependent. Ontogenetic shifts in ecological strategies appear to have been selected as a response to ontogeny‐dependent filters. Thus, strategies that favour less costly leaves and faster growth rates (relatively R‐selected) in juveniles shift towards C and/or S strategies in adulthood, depending on habitat productivity. Nevertheless, habitat‐dependent specialisation seems to be a major driver of ecological strategy selection in juveniles. Our study reveals ontogeny‐dependent strategies, offering a new approach to integrate plant development and functional specialisation. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.13221/suppinfo is available for this article.

The extent of specialization/generalization continuum in fruit-frugivore interactions at the individual level remains poorly explored. Here, we investigated the interactions between the Neotropical treelet Miconia irwinii (Melastomataceae) and its avian seed dispersers in Brazilian campo rupestre. We built an individual-based network to derive plant degree of interaction specialization regarding disperser species. Then, we explored how intraspecific variation in interaction niche breadth relates to fruit availability on individual plants in varying densities of fruiting conspecific neighbors, and how these factors affect the quantity of viable seeds dispersed. We predicted broader interaction niche breadths for individuals with larger fruit crops in denser fruiting neighborhoods. The downscaled network included nine bird species and 15 plants, which varied nearly five-fold in their degree of interaction specialization. We found positive effects of crop size on visitation and fruit removal rates, but not on degree of interaction specialization. Conversely, we found that an increase in the density of conspecific fruiting neighbors both increased visitation rate and reduced plant degree of interaction specialization. We suggest that tracking fruit-rich patches by avian frugivore species is the main driver of density-dependent intraspecific variation in plants' interaction niche breadth. Our study shed some light on the overlooked fitness consequences of intraspecific variation in interaction niches by showing that individuals along the specialization/generalization continuum may have their seed dispersed with similar effectiveness. Our study exemplifies how individual-based networks linking plants to frugivore species that differ in their seed dispersal effectiveness can advance our understanding of intraspecific variation in the outcomes of fruit-frugivore interactions.

Despite growing recognition of the conservation value of grassy biomes, our understanding of how to restore biodiverse tropical and subtropical grassy biomes (grasslands and savannas; TGB) remains limited. Several tools have recently been identified for TGB restoration, including prescribed fires, appropriate management of livestock and wild herbivores, tree cutting and shrub removal, invasive species control, and the reintroduction of native grasses and forbs via seeding or transplants. However, additional research for improved TGB restoration is needed. This article aims to identify ecological research priorities for TGB restoration. The following points are crucial to scale up TGB restoration and meet the challenges of the UN Restoration Decade. Research should focus on: disentangling the reasons why TGB are often undervalued and misunderstood; mapping TGB restoration opportunities; identifying regions where TGB and other biomes naturally exist as alternative stable states; recognizing areas with natural regeneration potential to avoid unnecessary intervention; restoring soil conditions; disentangling factors driving low seed quality, determining germination requirements and developing vegetative propagation techniques for TGB species; disentangling the limiting factors and key ecological processes underlying seedling establishment and community assembly; improving and validating long‐term management to mimic natural disturbance regimes; setting the minimum attributes of desirable TGB in terms of structure, composition, functioning, and resilience; and improving monitoring of restoration outcomes. Such research has the potential to advance theory, policy, and practice in TGB restoration, ultimately resulting in long‐term benefits for people and nature in some of the more neglected ecosystems of our planet.