Coloured scanning electron micrograph of a string of pollen grains from the evening primrose flower, Oenothera biennis. The grains are triangular in s

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Coloured scanning electron micrograph of a string of pollen grains from the evening primrose flower, Oenothera biennis. The grains are triangular in shape and are not shed individually, but in strings which are glued together by a series of sticky threads. All insect pollinated flowers (in comparison to wind pollinated plants) produce pollen grains that are oily and sticky. It is not known why the evening primrose goes a step further with sticky strings, but one suggestion has to do with the type of pollinating insects: small beetles with smooth bodies and no specialised hairs for attachment. Magnification: x35 at size.

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Size: 3662px × 4180px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: biennis, botany, coloured, evening, nature, oenothera, plant, plants, pollen, primros, primrose, reproduction, reproductive, sem, sp., type