North American Fruit Explorers mailing list at ibiblio

["William C. Garthright" <billg@inebraska.com>]

> It stated that sumac fruit are eaten by birds in winter when other fruits are not 
> available. The birds are unable to maintain weight on sumac (I presume due to limited 
> nutrient content/availability versus the energy cost and rate of digestion) but lose 
> weight at a considerably reduced rate compared to starvation. So we could look on sumac 
> as an "iron ration" of last resort for winter birds.


Fascinating! Plants use different "strategies" to get their seeds 
dispersed by birds. From what I've heard, fruits that are more appealing 
to birds (with a high fat or sugar content?) spoil relatively quickly. 
They are usually eaten quickly, but they must be, because they won't 
last long anyway. Other fruits are not as nutritious, so they're not as 
appealing. But that also means that they don't spoil quickly, so they'll 
last all winter in good condition. When the favored fruits are long 
gone, these are the only option, so they get eaten then.

I'm not going to guarantee this is correct, since it's just what I've 
heard... somewhere, but it made sense to me.

Bill
Lincoln, NE

--
The most remarkable thing about evolutionary theory is that, as the 
science of biochemistry has developed, as the science of cell biology, 
genetics, molecular biology, and other elements of science have 
developed, all of these have fit beautifully into the general framework 
described by Darwin almost one hundred fifty years ago. - Dr. Ken Miller