Perhaps the "purpose" is insecticidal. Ananas comosus wasn't always seedless
and the enzyme might have functioned as a toxin or repellant to insect larvae that
could have damaged the fruit before the seeds could be dispersed.


"Sean Houtman" wrote in message ...
From: "P van Rijckevorsel"

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

+ + +

One of the avenues to explore is the direct one:
these enzymes are in the fruits
the fruits are eaten, and hopefully the seeds are spread
the plants that has the fruits that are preferred by those animals that
spread the fruits the furthest or to the most suitable locations will
survive best
etc

Another is the systematic approach
in what plant groups do these enzyms occur?
do these plant groups have similar enzyms used for something else?
etc

I think the question sounds like, "why would a plant develop an enzyme that
digests a potential seed distributor?" Maybe the seeds are distributed by a
some organism with a salivary component that neutralizes the bromelin, and this
is a way to get specificity for a distributor.

Sean



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