The pollination networks between bees and flowers are not as robust as they were 100 years ago.
Based on a comparative study between contemporary research and that conducted by Illinois naturalist Charles Robertson between 1887 and 1916, the relationship between bees and plants has been shown to be much weaker today than it was in Robertson’s.
Many pollinators were active before their plants had flowered, plants were visited less, and many bees were not carrying as much usable pollen as they once did. Of the 532 pairings between plants and bees listed by Roberston, 406 had been lost, while 120 new pairings had been gained.
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