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Worldwide, human appropriation of ecosystems is disrupting plant-pollinator communities and pollination function through habitat conversion and landscape homogenisation. Conversion to agriculture is destroying and degrading semi-natural ecosystems while conventional land-use intensification (e.g. industrial management of large-scale monocultures with high chemical inputs) homogenises landscape structure and quality. Together, these anthropogenic processes reduce the connectivity of populations and erode floral and nesting resources to undermine pollinator abundance and diversity, and ultimately pollination services. Ecological intensification of agriculture represents a strategic alternative to ameliorate these drivers of pollinator decline while supporting sustainable food production, by promoting biodiversity beneficial to agricultural production through management practices such as intercropping, crop rotations, farm-level diversification and reduced agrochemical use. We critically evaluate its potential to address and reverse the land use and management trends currently degrading pollinator communities and potentially causing widespread pollination deficits. We find that many of the practices that constitute ecological intensification can contribute to mitigating the drivers of pollinator decline. Our findings support ecological intensification as a solution to pollinator declines, and we discuss ways to promote it in agricultural policy and practice.

Premise: The genus Calceolaria (Calceolariaceae) is emblematic of the Andes, is hypothesized to have originated as a recent, rapid radiation, and has important taxonomic needs. Additionally, the genus is a model for the study of specialized pollination systems, as its flowers are nectarless and many offer floral oils as a pollination reward collected by specialist bees. Despite their evolutionary and ecological significance, obtaining a resolved phylogeny for the group has proved difficult. To address this challenge, we present a new bait set for targeted sequencing of nuclear loci in Calceolariaceae and close relatives. Methods: We developed a bioinformatic workflow to use incomplete, low‐coverage genomes of 10 Calceolaria species to identify single‐copy loci suitable for phylogenetic studies and design baits for targeted sequencing. Results: Our approach resulted in the identification of 809 single‐copy loci (733 noncoding and 76 coding regions) and the development of 39,937 baits, which we validated in silico (10 specimens) and in vitro (29 Calceolariaceae and six outgroups). In both cases, the data allowed us to recover robust phylogenetic estimates. Discussion: Our results demonstrate the appropriateness of the bait set for sequencing recent and historic specimens of Calceolariaceae and close relatives, and open new doors for further investigation of the evolutionary history of this hyperdiverse genus. [ABSTRACT FROM AUTHOR]

Background and Aims The diversity of floral morphology among plant species has long captured the interest of biologists and led to the development of a number of explanatory theories. Floral morphology varies substantially within species, and the mechanisms maintaining this diversity are diverse. One possibility is that spatial variation in the pollinator fauna drives the evolution of spatially divergent floral ecotypes adapted to the local suite of pollinators. Another possibility is that geographic variation in the abiotic environment and local climatic conditions favours different floral morphologies in different regions. Although both possibilities have been shown to explain floral variation in some cases, they have rarely been competed against one another using data collected from large spatial scales. In this study, we assess floral variation in relation to climate and floral visitors in four oil-reward-specialized pollination interactions. Methods We used a combination of large-scale plant and pollinator samplings, morphological measures and climatic data. We analysed the data using spatial approaches, as well as traditional multivariate and structural equation modelling approaches. Key Results Our results indicate that the four species have different levels of specialization, and that this can be explained by their climatic niche breadth. In addition, our results show that, at least for some species, floral morphology can be explained by the identity of floral visitors, with climate having only an indirect effect. Conclusions Our results demonstrate that, even in very specialized interactions, both biotic and abiotic variables can explain a substantial amount of intraspecific variation in floral morphology. [ABSTRACT FROM AUTHOR]

Pollination by animals presents important advantages for plant reproduction. However, relying on biotic pollen dispersers also exposes plants to challenges, which include, for instance, the need to match the ecologies and phenologies of the pollinator species. Because of their ecological simplicity, specialized pollination systems are useful models to understand some of the variables that modulate how zoophilous pollination evolves, and whether or not species involved in pollination interactions respond jointly to evolutionary or ecological processes. In this study, we used a combination of field work, species distribution modeling (SDM), and geospatial analyses to investigate whether the number of floral visits by different pollinators in specialized zoophilous pollination interactions is correlated with the climatic suitability of the pollinator insects and, thus, to insect potential abundance. To do this, we investigated the pollination biology of four Calceolaria L. (Calceolariacea) species from central Chile, and we sampled across their whole ranges. Our results indicate that the four plant species are pollinated by different oil-bees of genera Centris Fabricius (Apidae: Centridini) and Chalepogenus Holmberg (Apidae: Tapinotaspidini), and that the number of floral visits varies at different localities. Our SDMs were accurate, successfully recovering the known ranges of the pollinators. Our analyses indicated that most plant species occur at localities in which insect climatic suitabilities are high. Furthermore, the number of pollinator visits at each locality was significantly and positively correlated with the insect suitability values, suggesting that matching high suitability areas can indeed increase the reproductive success of the plants. [ABSTRACT FROM AUTHOR]