The more specialized the flower becomes in its effort to attract a vector, the more at risk it may be if the relationship becomes too specialized and the vector disappears. Is the moth that pollinates Darwin's famous Angreacum still extant? Are there more than one moth that carry out this vital function?
It seems to me that orchids (and other flowering plants) would do best if they used many insects as pollinators, insects that perhaps would shun other plants. How specialized have most orchids become? Do they rely on a single species of pollinator? Or do they rely on a whole genera (or group of related genera) of insects or other vector for survival? How about those remarkably convoluted species like Stanhopea and Coryanthes; did they evolve this way in conjunction with a single insect species?
Do orchids that escape in the wild jungles of Hawaii ever find a substitute insect that does the job of their normal vector? Many years ago I saw a number of Phalaenopsis on tree branches in Asuncion, Paraguay, thoughtfully (or thoughtlessly) put there by members of a local orchid society. I vaguely remember a couple of seed pods on them. Did they originate with the ubiquitous toothpick, or did a confused insect do the job?
And how about the vector. The flowers are not always there for the taking. Clearly they must philander around with other flowers when there are none of their favorite orchids in bloom. What other kinds of flowers do they favor?
Then there is man and his toothpick (is this the universal tool for this purpose). He selects plants which please him (don't insects do the same thing?) and insures that they breed with who knows what. Is this evolution by unnatural selection?
More thoughts, anyone?
Martin
_______________________________________________ the OrchidGuide Digest (OGD) [EMAIL PROTECTED] http://lists.orchidguide.com/mailman/listinfo/orchids
