|GRAB, HEATHER - Cornell University - New York|
|AMON, NOLAN - Cornell University - New York|
|BLITZER, ELEANOR - Carroll College|
|GIBBS, JASON - University Of Manitoba|
|PARK, MIA - University Of North Dakota|
Submitted to: Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/12/2018
Publication Date: 1/18/2019
Citation: Grab, H., Branstetter, M.G., Amon, N., Blitzer, E.J., Gibbs, J., Park, M. 2019. Agriculturally dominated landscapes reduce bee phylogenetic diversity and pollination services. Science. 363(6424):282-284. https://doi.org/10.1126/science.aat6016.
Interpretive Summary: Bees are responsible for pollinating the majority of our most valuable and nutritious crops, but habitat loss and agricultural intensification have been implicated in recent bee declines, potentially threatening food security. Understanding how land use change affects bee diversity is critical to safeguarding and improving agricultural productivity. The diversity of bees and their relatedness was quantified in eastern apple orchards using molecular data and combined with extensive data on bee abundance, bee biology, fruit quality and yield, and land use patterns around orchards. Loss of natural areas around apple orchards was associated with non-random reductions in bee diversity. Additionally, it was found that orchards with more distantly related bee species had improved crop yield and quality in two apple varieties. These results suggest that it is important to conserve not only the number of bee species, but also diversity in their types, in order to boost crop production. Overall, conservation practices that promote bee diversity, such as the preservation of natural areas near or in farms, will likely help maintain diverse pollinator communities into the future.
Technical Abstract: Agriculturally driven land use change threatens global biodiversity and has the potential to reshape the tree of life by favoring the persistence of some lineages over others. Yet it is unclear if loss of phylogenetic diversity compromises the delivery of ecosystem services. To address this critical knowledge gap, we combine extensive land cover, pollinator survey and crop data with a complete time-calibrated phylogenomic tree for this diverse bee community. Pollinator communities in highly agricultural landscapes contain 230 million fewer years of evolutionary history and loss of pollinator phylogenetic diversity was strongly associated with reduced crop yield and quality. Our study is the first to link landscape mediated changes in the phylogenetic structure of natural communities to the disruption of ecosystem services. Practices that measure their success only by the number of species conserved may fail to protect the full diversity of life impacted by these stressors.