Specialized and generalized pollen-collection strategies in an ancient bee lineage

Autor(en)
Torsten Wappler, Conrad C. Labandeira, Michael S. Engel, Reinhard Zetter, Fridgeir Grimsson
Abstrakt

Iconic examples of insect pollination have emphasized narrowly specialized pollinator mutualisms such as figs and fig wasps [1] and yuccas and yucca moths [2]. However, recent attention by pollination ecologists has focused on the broad spectra of pollinated plants by generalist pollinators such as bees. Bees have great impact for formulating hypotheses regarding specialization versus generalization in pollination mutualisms [3, 4]. We report the pollination biology of six northern European species of an extinct tribe of pollen-basket-bearing apine bees, Electrapini, of early–middle Eocene age, examined from two deposits of 48 and 44 million years in age [5]. These bees exhibit a pattern of
generalized, incidental pollen occurring randomly on their heads, thoraces, and abdomens, obtained from diverse, nectar-bearing plants. By contrast, a more restricted suite of pollen was acquired for metatibial pollen baskets (corbiculae) of the same bee taxa from a taxonomically much narrower suite of arborescent, evergreen hosts with uniform flower structure. The stereotyped plant sources of the specialist strategy of pollen collection consisted of pentamerous, radially symmetrical flowers with a conspicuous gynoecium surrounded by prominent
nectar reward, organized in structurally similar compound inflorescences. Pollen specialization in bees occurs not for efficient pollination but rather in the corbiculate Electrapini as food for bee larvae (brood) and involves packing corbiculae with moistened pollen that rapidly loses viability with age.
This specialist strategy was a well-developed preference by the early Eocene, providing a geochronologic midpoint assessment of bee pollen-collection
strategies.

Organisation(en)
Institut für Paläontologie
Externe Organisation(en)
Rheinische Friedrich-Wilhelms-Universität Bonn, University of Kansas, Smithsonian National Museum of Natural History, University of Maryland, College Park
Journal
Current Biology
Band
25
Seiten
3092-3098
Anzahl der Seiten
7
ISSN
0960-9822
DOI
https://doi.org/10.1016/j.cub.2015.09.021
Publikationsdatum
2015
Peer-reviewed
Ja
ÖFOS 2012
105117 Paläobotanik
Schlagwörter
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/specialized-and-generalized-pollencollection-strategies-in-an-ancient-bee-lineage(59a32add-2d44-420a-b098-9c4a2ed3c992).html