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Current Opinion in Insect Science Apr 2020Insect pollinators are becoming visible to societies. Many peer-reviewed papers evidence biophysical and ecological aspects of managed and non-managed insect... (Review)
Review
Insect pollinators are becoming visible to societies. Many peer-reviewed papers evidence biophysical and ecological aspects of managed and non-managed insect pollinators. Evidence on stressors of declines yield peer-reviewed calls for action. Yet, insect pollinator declines are inherently a human issue, driven by a history of land-use trends, changes in technologies, and socio-cultural perceptions that unwittingly cause and perpetuate declines. Conservation requires integrating social and ecological understandings to reconfigure human behaviors across societies' sectors. We review recent literature on the social and cultural dimensions of insect pollinators. People now like bees. We discuss the social challenges and opportunities that accompany this newfound public enthusiasm. These include the generalization of honey bees as representative of bee diversity and pollinator conservation issues, the changing perceptions of pollinators, the paucity of policy research, and how any call to 'save the bees' must be a call to stabilize agriculture. We call for greater coordination among biological and socio-cultural researchers to advance insect pollinator conservation practices and policies fit for the Anthropocene.
Topics: Agriculture; Animals; Bees; Conservation of Natural Resources; Ecosystem; Pollination; Public Opinion
PubMed: 32375115
DOI: 10.1016/j.cois.2020.04.001 -
Annual Review of Entomology Jan 2023There is growing awareness of pollinator declines worldwide. Conservation efforts have mainly focused on finding the direct causes, while paying less attention to... (Review)
Review
There is growing awareness of pollinator declines worldwide. Conservation efforts have mainly focused on finding the direct causes, while paying less attention to building a systemic understanding of the fragility of these communities of pollinators. To fill this gap, we need operational measures of network resilience that integrate two different approaches in theoretical ecology. First, we should consider the range of conditions compatible with the stable coexistence of all of the species in a community. Second, we should address the rate and shape of network collapse once this safe operational space is exited. In this review, we describe this integrative approach and consider several mechanisms that may enhance the resilience of pollinator communities, chiefly rewiring the network of interactions, increasing heterogeneity, allowing variance, and enhancing coevolution. The most pressing need is to develop ways to reduce the gap between these theoretical recommendations and practical applications. This perspective shifts the emphasis from traditional approaches focusing on the equilibrium states to strategies that allow pollination networks to cope with global environmental change.
Topics: Animals; Ecosystem; Ecology; Pollination; Plants
PubMed: 36206771
DOI: 10.1146/annurev-ento-120120-102424 -
Ecology Letters Sep 2023Urbanization is increasing worldwide, with major impacts on biodiversity, species interactions and ecosystem functioning. Pollination is an ecosystem function vital for... (Meta-Analysis)
Meta-Analysis Review
Urbanization is increasing worldwide, with major impacts on biodiversity, species interactions and ecosystem functioning. Pollination is an ecosystem function vital for terrestrial ecosystems and food security; however, the processes underlying the patterns of pollinator diversity and the ecosystem services they provide in cities have seldom been quantified. Here, we perform a comprehensive meta-analysis of 133 studies examining the effects of urbanization on pollinators and pollination. Our results confirm the widespread negative impacts of urbanization on pollinator richness and abundance, with Lepidoptera being the most affected group. Furthermore, pollinator responses were found to be trait-specific, with below-ground nesting and solitary Hymenoptera, and spring flyers more severely affected by urbanization. Meanwhile, cities promote non-native pollinators, which may exacerbate conservation risks to native species. Surprisingly, despite the negative effects of urbanization on pollinator diversity, pollination service measured as seed set is enhanced in non-tropical cities likely due to abundant generalists and managed pollinators therein. We emphasize that the richness of local flowering plants could mitigate the negative impacts of urbanization on pollinator diversity. Overall, the results demonstrate the varying magnitudes of multiple moderators on urban pollinators and pollination services and could help guide conservation actions for biodiversity and ecosystem function for a sustainable future.
Topics: Bees; Urbanization; Ecosystem; Pollination; Biodiversity; Cities; Flowers
PubMed: 37345567
DOI: 10.1111/ele.14277 -
Biological Reviews of the Cambridge... Dec 2021Global changes are severely affecting pollinator insect communities worldwide, resulting in repeated patterns of species extirpations and extinctions. Whilst negative... (Review)
Review
Global changes are severely affecting pollinator insect communities worldwide, resulting in repeated patterns of species extirpations and extinctions. Whilst negative population trends within this functional group have understandably received much attention in recent decades, another facet of global changes has been overshadowed: species undergoing expansion. Here, we review the factors and traits that have allowed a fraction of the pollinating entomofauna to take advantage of global environmental change. Sufficient mobility, high resistance to acute heat stress, and inherent adaptation to warmer climates appear to be key traits that allow pollinators to persist and even expand in the face of climate change. An overall flexibility in dietary and nesting requirements is common in expanding species, although niche specialization can also drive expansion under specific contexts. The numerous consequences of wild and domesticated pollinator expansions, including competition for resources, pathogen spread, and hybridization with native wildlife, are also discussed. Overall, we show that the traits and factors involved in the success stories of expanding pollinators are mostly species specific and context dependent, rendering generalizations of 'winning traits' complicated. This work illustrates the increasing need to consider expansion and its numerous consequences as significant facets of global changes and encourages efforts to monitor the impacts of expanding insect pollinators, particularly exotic species, on natural ecosystems.
Topics: Animals; Bees; Climate Change; Ecosystem; Insecta; Pollination; Species Specificity
PubMed: 34288353
DOI: 10.1111/brv.12777 -
Current Biology : CB Oct 2022Johnson gives an overview of bird pollinators and the plant species they pollinate.
Johnson gives an overview of bird pollinators and the plant species they pollinate.
Topics: Animals; Pollination; Flowers; Birds; Plants
PubMed: 36283359
DOI: 10.1016/j.cub.2022.06.081 -
Philosophical Transactions of the Royal... Jun 2022Evidence from the last few decades indicates that pollinator abundance and diversity are at risk, with many species in decline. Anthropogenic impacts have been the focus...
Evidence from the last few decades indicates that pollinator abundance and diversity are at risk, with many species in decline. Anthropogenic impacts have been the focus of much recent work on the causes of these declines. However, natural processes, from plant chemistry, nutrition and microbial associations to landscape and habitat change, can also profoundly influence pollinator health. Here, we argue that these natural processes require greater attention and may even provide solutions to the deteriorating outlook for pollinators. Existing studies also focus on the decline of individuals and colonies and only occasionally at population levels. In the light of this we redefine pollinator health and argue that a top-down approach is required focusing at the ecological level of communities. We use examples from the primary research, opinion and review articles published in this special issue to illustrate how natural processes influence pollinator health, from community to individuals, and highlight where some of these processes could mitigate the challenges of anthropogenic and natural drivers of change. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.
Topics: Ecosystem; Humans; Pollination
PubMed: 35491596
DOI: 10.1098/rstb.2021.0154 -
Environmental Pollution (Barking, Essex... Mar 2022Common air pollutants, such as nitrogen oxides (NO), emitted in diesel exhaust, and ozone (O), have been implicated in the decline of pollinating insects. Reductionist...
Common air pollutants, such as nitrogen oxides (NO), emitted in diesel exhaust, and ozone (O), have been implicated in the decline of pollinating insects. Reductionist laboratory assays, focused upon interactions between a narrow range of flowering plant and pollinator species, in combination with atmospheric chemistry models, indicate that such pollutants can chemically alter floral odors, disrupting the cues that foraging insects use to find and pollinate flowers. However, odor environments in nature are highly complex and pollination services are commonly provided by suites of insect species, each exhibiting different sensitivities to different floral odors. Therefore, the potential impacts of pollution-induced foraging disruption on both insect ecology, and the pollination services that insects provide, are currently unknown. We conducted in-situ field studies to investigate whether such pollutants could reduce pollinator foraging and as a result the pollination ecosystem service that those insects provide. Using free-air fumigation, we show that elevating diesel exhaust and O, individually and in combination, to levels lower than is considered safe under current air quality standards, significantly reduced counts of locally-occurring wild and managed insect pollinators by 62-70% and their flower visits by 83-90%. These reductions were driven by changes in specific pollinator groups, including bees, flies, moths and butterflies, and coincided with significant reductions (14-31%) in three different metrics of pollination and yield of a self-fertile test plant. Quantifying such effects provides new insights into the impacts of human-induced air pollution on the natural ecosystem services upon which we depend.
Topics: Air Pollutants; Animals; Bees; Butterflies; Ecosystem; Flowers; Insecta; Pollination
PubMed: 35063287
DOI: 10.1016/j.envpol.2022.118847 -
Trends in Plant Science Mar 2021Nectar is the most important reward offered by flowering plants to pollinators for pollination services. Since pollinator decline has emerged as a major threat for... (Review)
Review
Nectar is the most important reward offered by flowering plants to pollinators for pollination services. Since pollinator decline has emerged as a major threat for agriculture, and the food demand is growing globally, studying the nectar gland is of utmost importance. Although the genetic mechanisms that control the development of angiosperm flowers have been quite well understood for many years, the development and maturation of the nectar gland and the secretion of nectar in synchrony with the maturation of the sexual organs appears to be one of the flower's best-kept secrets. Here we review key findings controlling these processes. We also raise key questions that need to be addressed to develop crop ecological functions that take into consideration pollinators' needs.
Topics: Flowers; Plant Nectar; Pollination; Reproduction
PubMed: 33246889
DOI: 10.1016/j.tplants.2020.11.002 -
Protoplasma Mar 2024Gametophytic self-incompatibility (GSI) has been mainly described in species-rich clades within Orchidaceae. We report GSI for a genus within Maxillariinae, one of the...
Gametophytic self-incompatibility (GSI) has been mainly described in species-rich clades within Orchidaceae. We report GSI for a genus within Maxillariinae, one of the most conspicuous and diverse subtribes of neotropical orchids. Here, we describe the reproductive system of Brasiliorchis picta, B. phoenicanthera, and B. porphyrostele. Anatomical studies of fruit development showed that pollen tubes of aborted, self-pollinated flowers degenerate half-way in the stylar channel and never reach the ovules. Spontaneous self-pollination and emasculation set no fruits for none of the sampled species, thus supporting the hypothesis that these three species studied rely on the agency of pollinators and pollinator-mediated cross-pollination to set fruit. Fruit set from cross-pollinations ranged from 33.4 to 77.5%. One self-pollinated fruit of B. porphyrostele developed to completion. All other fruits aborted between 10 and 21 days after pollination. These data support previous evidence of variable strength GSI being exhibited in orchid species. Additional studies of self-incompatibility systems are needed to evaluate their role in species diversification and evolution of reproductive strategies in Maxillariinae and to allow for effective conservation strategies of threatened orchid species.
Topics: Pollen; Reproduction; Pollination; Fruit; Flowers; Orchidaceae
PubMed: 37787780
DOI: 10.1007/s00709-023-01895-x -
Trends in Ecology & Evolution May 2023The global decline in insect diversity threatens pollination services, potentially impacting crop production and food security. Here, we argue that this looming... (Review)
Review
The global decline in insect diversity threatens pollination services, potentially impacting crop production and food security. Here, we argue that this looming pollination crisis is generally approached from an ecological standpoint, and that consideration of evolutionary principles offers a novel perspective. First, we outline that wild plant species have overcome 'pollination crises' throughout evolutionary history, and show how associated principles can be applied to crop pollination. We then highlight technological advances that can be used to adapt crop flowers for optimal pollination by local wild pollinators, especially by increasing generalization in pollination systems. Thus, synergies among fundamental evolutionary research, genetic engineering, and agro-ecological science provide a promising template for addressing a potential pollination crisis, complementing much-needed strategies focused on pollinator conservation.
Topics: Animals; Pollination; Biological Evolution; Insecta; Flowers; Adaptation, Physiological
PubMed: 36737302
DOI: 10.1016/j.tree.2022.12.010