Background and Aims: Elevation is a major factor shaping plant populations on a global scale. At the same time, reproductive traits play a major role in plant fitness. With increasing elevation and increasingly harsh conditions, decreases in pollinator visitation rates, sexual investment, seed set and heterozygosity (owing to increased selfing) are expected. In response, selection and/or phenotypic plasticity could lead to an increase in floral displays by plants to increase their attractiveness to pollinators and compensate for the negative fitness impacts of reduced pollinator activity. A large body of literature tests these hypotheses at the among-species level, but empirical evidence at the population level (i.e. wihin species), where adaptive change might occur, is still limited to species-specific studies. Unravelling the global patterns of change in the reproductive traits, flower visitation rates and heterozygosity of plant populations across variable environmental conditions, especially climate, can help us to understand how species are able to cope with shifting conditions associated with global change, particularly in mountains. Here, we adopted meta-analytical approaches to assess the reproductive changes of plant populations in response to elevation on a global scale. Methods: We used a data set with 243 paired populations of plants at ‘lower’ and ‘higher’ elevations, spanning an elevation range of 0–4380 m a.s.l. and taken from 121 angiosperm species and 115 published studies. We analysed changes in the number of flowers, their size and longevity, pollen production, flower visitation rate, seed set and expected heterozygosity. We then tested whether the observed patterns for each trait were dependent upon plant phylogeny and various ecogeographical factors and species traits. Key Results: We found no evidence of elevation having a global effect on the reproductive traits of angiosperm populations. This null global pattern was not affected by geography or phylogenetics. Conclusions: Our results suggest that changes in reproductive traits, flower visitation rates and heterozygosity in plant populations across elevations are specific to each species and ecosystem. Hence, macroevolutionary (across species) and macroecological patterns of elevation of plant reproduction reported previously are apparently not simply the outcome of microevolutionary changes (within species). This apparent specificity of response across plant species poses difficulties in predicting the effects of global changes and, specifically, climatic changes, on the fate of plant species, populations and communities.

Competition is an important biological filter that can define crucial features of species’ natural history, like survival and reproduction success. We evaluated in the Brazilian tropical savanna whether two sympatric and congenereric species, Qualea multiflora Mart. and Q. parviflora Mart. (Vochysiaceae), compete for pollinator services, testing whether there is a better competitor or whether plants present any anti-competitive mechanism. Additionally, we investigated the breeding system, pollinators, and flowering phenology of both species. The results showed that Q. multiflora and Q. parviflora are dependent on pollinators for fruit formation, as they exhibited a self-incompatible and non-agamospermic breeding system. These plants shared the same guild of pollinators, which was formed by bees and hummingbirds, and an overlap in the flower visitation time was observed. Each plant species had different pollinator attraction strategies: Q. multiflora invested in floral resource quality, while Q. parviflora invested in resource quantity. The blooming time showed a temporal flowering partition, with highly sequential flowering and no overlap. Qualea parviflora bloomed intensely from September to October, while Q. multiflora bloomed from November to January, with the flowering peak occurring in December. The two Qualea species have morphologically similar flowers, are sympatric, and share the same pollinator community, with overlapping foraging activity during the day. However, they do not compete for pollinator services as they exhibit an anti-competitive mechanism mediated by temporal flowering partition.