[Pollinator] Flowers and pollinators

[Ladadams at aol.com]

Flowers shape themselves to guide their pollinators to the pollen
Why do flowers specialize on different pollinators? For example, both bats 
and hummingbirds pollinate plants in tropical forests; why adapt to just one 
instead of using both? Biologists often assume that tradeoffs contribute to such 
specialization (the jack of all pollinators is master of none), yet 
surprisingly little evidence exists in support of this idea. 
 

Nathan Muchhala from the University of Miami explored pollinator 
specialization through experiments with bats, hummingbirds, and artificial flowers in 
cloudforests of Ecuador. 

In a study published in the April issue of the American Naturalist, he 
reports that the fit between flower and pollinator is key: bats pollinate wide 
flowers better, while hummingbirds transfer more pollen between narrow flowers. 
Videotaping demonstrated that a poor fit fails to correctly guide the pollinator 
while feeding. This tradeoff in adapting to bats vs. hummingbirds is strong 
enough to favor specialization on one or the other. 

Nathan says, "While all leaves tend to look similar, flowers come in a 
spectacular variety of shapes and colors. This study suggests tradeoffs in adapting 
to different pollinators may have played an important role in the evolution of 
such diversity." 

Source: University of Chicago 
 
Laurie Davies Adams
Executive Director
Coevolution Institute
423 Washington St. 5th
San Francisco, CA 94111
415 362 1137
LDA at coevolution.org
_http://www.coevolution.org/_ (http://www.coevolution.org/) 
_http://www.pollinator.org/_ (http://www.pollinator.org/) 
_http://www.nappc.org/_ (http://www.nappc.org/) 

Bee Ready for National Pollinator Week:  June 24-30, 2007.  Contact us 
for more information at www.pollinator.org 

Our future flies on the wings of pollinators.



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