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Medusozoa (Cnidaria) are characterized by diverse life cycles, with different semaphoronts (medusa, medusoid, fixed gonophore, polyp) representing the sexual phase and carrying the gametes. Although egg size is often considered a proxy to understand reproductive and developmental traits of medusozoans, understanding of the processes influencing egg size variation in the group under an evolutionary context is still limited. We carried out a comprehensive review of the variation of egg size in Medusozoa to test whether this variation is related to biological/sexual or environmental traits. Egg size presents a strong phylogenetic signal (λ = 0.79, K = 0.67), explaining why closely related species with different reproductive strategies and different individual sizes have similar egg sizes. However, variation in egg size is influenced by the number of eggs, depth and temperature, with larger eggs frequently present in species with few eggs (1–15), in deep-sea species and in cold-water species. Conversely, the production of small eggs among cold-water species of Staurozoa might be associated with the development of a small benthic larvae in this group. Our study reinforces that egg sizes respond to reproductive and environmental traits, although egg size is highly conserved within medusa classes. [ABSTRACT FROM AUTHOR]

Enhancing biodiversity‐based ecosystem services can generate win–win opportunities for conservation and agricultural production. Pollination and pest control are two essential agricultural services provided by mobile organisms, many depending on native vegetation networks beyond the farm scale. Many studies have evaluated the effects of landscape changes on such services at small scales. However, several landscape management policies (e.g. selection of conservation sites) and associated funding allocation occur at much larger spatial scales (e.g. state or regional level). Therefore, it is essential to understand whether the links between landscape, ecosystem services and crop yields are robust across broad and heterogeneous regional conditions.Here, we used data from 610 Brazilian municipalities within the Atlantic Forest region (~50 Mha) and show that forest is a crucial factor affecting coffee yields, regardless of regional variations in soil, climate and management practices. We found forest cover surrounding coffee fields was better at predicting coffee yields than forest cover at the municipality level. Moreover, the positive effect of forest cover on coffee yields was stronger for Coffea canephora, the species with higher pollinator dependence, than for Coffea arabica. Overall, coffee yields were highest when they were near to forest fragments, mostly in landscapes with intermediate to high forest cover (>20%), above the biodiversity extinction threshold.Coffee cover was the most relevant management practice associated with coffee yield prediction. An increase in crop area was associated with a higher yield, but mostly in high forest covers municipalities. Other localized management practices like irrigation, pesticide use, organic manure and honeybee density had little importance in predicting coffee yields than landscape structure parameters. Neither the climatic or topographic variables were as relevant as forest cover at predicting coffee yields.Synthesis and application. Our work provides evidence that landscape relationships with ecosystem service provision are consistent across regions with different agricultural practices and environmental conditions. These results provide a way in which landscape management can articulate small landscape management with regional conservation goals. Policies directed towards increasing landscape interspersion of coffee fields with forest remnants favour spillover process, and can thus benefit the provision of biodiversity‐based ecosystem services, increasing agricultural productivity. Such interventions can generate win–win situations favouring biodiversity conservation and increased crop yields across large regions. [ABSTRACT FROM AUTHOR]

Pollen is the main protein source for honeybee brood and so colony development relies heavily on the availability of pollen in the environment. Intensification of agriculture and climate seasonality are known to alter honeybee pollen intake in temperate regions through changes in resource availability; however, little is known about how honeybees respond to such environmental factors in tropical regions.Pollen collected by honeybees was sampled from apiaries in a Neotropical highland region of Colombia. Pollen species were identified and the effects of landscape diversity, forest area and mean monthly precipitation on the pollen intake by honeybees were evaluated for all pollen species together and pollen species segregated according to forest and anthropic areas.Honeybees were found to be much more associated with anthropic than forest pollen species regardless of landscape structure or precipitation. However, pollen intake from all species and forest species responded positively to landscape diversity and forest area. Precipitation was found not to be related to the overall amount and overall richness of pollen collected by honeybees. Nonetheless, overall pollen diversity was negatively affected by precipitation in less diverse landscapes, whereas anthropic pollen diversity was negatively affected by precipitation in more forested landscapes. [ABSTRACT FROM AUTHOR]

Across the globe, wild bees are threatened by ongoing natural habitat loss, risking the maintenance of plant biodiversity and agricultural production. Despite the ecological and economic importance of wild bees and the fact that several species are now managed for pollination services worldwide, little is known about how land use and beekeeping practices jointly influence gene flow. Using stingless bees as a model system, containing wild and managed species that are presumed to be particularly susceptible to habitat degradation, here we examine the main drivers of tropical bee gene flow. We employ a novel landscape genetic approach to analyse data from 135 populations of 17 stingless bee species distributed across diverse tropical biomes within the Americas. Our work has important methodological implications, as we illustrate how a maximum-likelihood approach can be applied in a meta-analysis framework to account for multiple factors, and weight estimates by sample size. In contrast to previously held beliefs, gene flow was not related to body size or deforestation, and isolation by geographic distance ( IBD) was significantly affected by management, with managed species exhibiting a weaker IBD than wild ones. Our study thus reveals the critical importance of beekeeping practices in shaping the patterns of genetic differentiation across bee species. Additionally, our results show that many stingless bee species maintain high gene flow across heterogeneous landscapes. We suggest that future efforts to preserve wild tropical bees should focus on regulating beekeeping practices to maintain natural gene flow and enhancing pollinator-friendly habitats, prioritizing species showing a limited dispersal ability. [ABSTRACT FROM AUTHOR]

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Setting aside private land is an essential component of the biodiversity crisis response. In Brazil, landowners are required to have Legal Reserves (LR) (20%–80% of their property set aside for native vegetation) which, if degraded, need to be restored. Alternatively, landowners can compensate for an LR deficit by purchasing surplus credits. Each landowner can define the location and spatial arrangement of their LR, affecting the reserve's ability to maintain biodiversity and provide ecosystem services (ES). We used hierarchical models to determine drivers for the amount and location of those LR in 3622 farms. The likelihood of setting aside part of the farm as LR (avoiding off-farm compensation) increased with farm size and extent of native vegetation cover, particularly for riparian areas and steep slopes, where conserving vegetation is also mandated in what are called Areas of Permanent Protection (APP). Properties with APP were more likely to meet the full LR requirement within their areas if located in areas of higher transportation costs and lower agricultural suitability. Within properties, the location of LR was mostly in areas with low agricultural suitability, high transportation cost, and close to APP. Landowners' decisions intend to maximize property income and reduce restoration costs, resulting in a spatial pattern similar to public protected areas — usually located on marginal land for agriculture. These areas do not necessarily provide the greatest biodiversity and ES benefits, suggesting that government interventions may be needed to encourage landowners to set aside native vegetation in ways that maximize conservation and ES outcomes. [Display omitted] • Economic processes determine landowner decision around private land conservation. • Decision-making maximizes property income and reduces restoration costs. • Farms with low vegetation cover are less likely to restore or set in-farm reserves. • Conservation in-farm in our area has a similar location bias to protected areas. [ABSTRACT FROM AUTHOR]

Male flowers of the wind-pollinated, dioecious shrub Boehmeria caudata Sw. release pollen explosively, possibly stimulated by anther dehydration in response to temporarily dry conditions coupled with hydrostatic pressure in the filament. In the Brazilian Atlantic rain forest, the daily frequency of male flower anthesis peaked between 1000-1200 h (GMT −3) and was positively correlated with rising temperature, wind currents, and direct insolation, but negatively correlated with relative humidity. A generalized linear mixed model predicts the probability of pollen release under different conditions of relative humidity and wind. Receptive stigmas on female flowers were found at any time of day: individual stigmas were receptive (H2O2 test) for at least two days. Beetles and halictid bees were observed feeding on pollen from staminate flowers, but probably did not affect pollination because they did not seem to visit pistillate flowers. Individual plants of this apparently ruderal species grow along road edges and show aggregated (clumped) spatial dispersion. The overall sex ratio we found was 29 females to 43 males, with one monoecious plant in a total transect distance of 6319 m. Pollen traps were placed on the female plants to measure pollen arrival. Pollen capture was higher on the more exposed road-facing side and positively related to male plant density. [ABSTRACT FROM AUTHOR]

Animal pollinators are globally threatened by anthropogenic land use change and agricultural intensification. The yield of many food crops is therefore negatively impacted because they benefit from biotic pollination. This is especially the case in the tropics. For instance, fruit set of Coffea arabica has been shown to increase by 10–30% in plantations with a high richness of bee species, possibly influenced by the availability of surrounding forest habitat. Here, we performed a global literature review to (1) assess how much animal pollination enhances coffee fruit set, and to (2) examine the importance of the amount of forest cover, distance to nearby forest and forest canopy density for bee species richness and coffee fruit set. Using a systematic literature review, we identified eleven case studies with a total of 182 samples where fruit set of C. arabica was assessed. We subsequently gathered forest data for all study sites from satellite imagery. We modelled the effects of open (all forest with a canopy density of ≥25%), closed (≥50%) and dense (≥75%) forests on pollinator richness and fruit set of coffee. Overall, we found that animal pollination increases coffee fruit set by ~18% on average. In only one of the case studies, regression results indicate a positive effect of dense forest on coffee fruit set, which increased with higher forest cover and shorter distance to the forest. Against expectations, forest cover and distance to open forest were not related to bee species richness and fruit set. In summary, we provide strong empirical support for the notion that animal pollinators increase coffee fruit set. Forest proximity had little overall influence on bee richness and coffee fruit set, except when farms were surrounded by dense tropical forests, potentially because these may provide high-quality habitats for bees pollinating coffee. We, therefore, advocate that more research is done to understand the biodiversity value of dense forest for pollinators, notably assessing the mechanisms underlying the importance of forest for pollinators and their pollination services. • In a meta-study, we gathered 11 case studies that assessed fruit set of C. arabica. • We assessed effects of pollinators and forest on coffee fruit set within each study. • Globally, we found that animal pollination increases coffee fruit set by ~18%. • One study indicates that forest with a dense canopy may benefit coffee pollination. • We suggest more research on the biodiversity value of dense forest for pollinators. [ABSTRACT FROM AUTHOR]

Medusozoa (Cnidaria) are characterized by diverse life cycles, with different semaphoronts (medusa, medusoid, fixed gonophore, polyp) representing the sexual phase and carrying the gametes. Although egg size is often considered a proxy to understand reproductive and developmental traits of medusozoans, understanding of the processes influencing egg size variation in the group under an evolutionary context is still limited. We carried out a comprehensive review of the variation of egg size in Medusozoa to test whether this variation is related to biological/sexual or environmental traits. Egg size presents a strong phylogenetic signal ( λ = 0.79, K = 0.67), explaining why closely related species with different reproductive strategies and different individual sizes have similar egg sizes. However, variation in egg size is influenced by the number of eggs, depth and temperature, with larger eggs frequently present in species with few eggs (1-15), in deep-sea species and in cold-water species. Conversely, the production of small eggs among cold-water species of Staurozoa might be associated with the development of a small benthic larvae in this group. Our study reinforces that egg sizes respond to reproductive and environmental traits, although egg size is highly conserved within medusa classes.