TY  - JOUR
A1  - Voulgari‐Kokota, Anna
A1  - Ankenbrand, Markus J.
A1  - Grimmer, Gudrun
A1  - Steffan‐Dewenter, Ingolf
A1  - Keller, Alexander
T1  - Linking pollen foraging of megachilid bees to their nest bacterial microbiota
JF  - Ecology and Evolution
N2  - Solitary bees build their nests by modifying the interior of natural cavities, and they provision them with food by importing collected pollen. As a result, the microbiota of the solitary bee nests may be highly dependent on introduced materials. In order to investigate how the collected pollen is associated with the nest microbiota, we used metabarcoding of the ITS2 rDNA and the 16S rDNA to simultaneously characterize the pollen composition and the bacterial communities of 100 solitary bee nest chambers belonging to seven megachilid species. We found a weak correlation between bacterial and pollen alpha diversity and significant associations between the composition of pollen and that of the nest microbiota, contributing to the understanding of the link between foraging and bacteria acquisition for solitary bees. Since solitary bees cannot establish bacterial transmission routes through eusociality, this link could be essential for obtaining bacterial symbionts for this group of valuable pollinators.
KW  - foraging patterns
KW  - nest microbiota
KW  - plant–microbe–pollinator triangle
KW  - pollination network
KW  - solitary bees
KW  - wild bees
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201749
SN  - 00
VL  - 2019
IS  - 9
ER  - 
TY  - JOUR
A1  - Sponsler, Douglas B.
A1  - Requier, Fabrice
A1  - Kallnik, Katharina
A1  - Classen, Alice
A1  - Maihoff, Fabienne
A1  - Sieger, Johanna
A1  - Steffan‐Dewenter, Ingolf
T1  - Contrasting patterns of richness, abundance, and turnover in mountain bumble bees and their floral hosts
JF  - Ecology
N2  - Environmental gradients generate and maintain biodiversity on Earth. Mountain slopes are among the most pronounced terrestrial environmental gradients, and the elevational structure of species and their interactions can provide unique insight into the processes that govern community assembly and function in mountain ecosystems. We recorded bumble bee–flower interactions over 3 years along a 1400‐m elevational gradient in the German Alps. Using nonlinear modeling techniques, we analyzed elevational patterns at the levels of abundance, species richness, species β‐diversity, and interaction β‐diversity. Though floral richness exhibited a midelevation peak, bumble bee richness increased with elevation before leveling off at the highest sites, demonstrating the exceptional adaptation of these bees to cold temperatures and short growing seasons. In terms of abundance, though, bumble bees exhibited divergent species‐level responses to elevation, with a clear separation between species preferring low versus high elevations. Overall interaction β‐diversity was mainly caused by strong turnover in the floral community, which exhibited a well‐defined threshold of β‐diversity rate at the tree line ecotone. Interaction β‐diversity increased sharply at the upper extreme of the elevation gradient (1800–2000 m), an interval over which we also saw steep decline in floral richness and abundance. Turnover of bumble bees along the elevation gradient was modest, with the highest rate of β‐diversity occurring over the interval from low‐ to mid‐elevation sites. The contrast between the relative robustness bumble bee communities and sensitivity of plant communities to the elevational gradient in our study suggests that the strongest effects of climate change on mountain bumble bees may be indirect effects mediated by the responses of their floral hosts, though bumble bee species that specialize in high‐elevation habitats may also experience significant direct effects of warming.
KW  - alpine plants
KW  - climate
KW  - elevation gradient
KW  - mountain ecology
KW  - pollination network
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-287199
VL  - 103
IS  - 7
ER  -