Paul J. Johnson wrote: >In the ideal situation, genera are clusters of closely related species [that] >share a >basic degree of relatedness [...]. Indeed, consider the pollination >syndromes, where there are trends of selection for certain kinds of >pollinating capabilities: moths, bees, beetles, birds, bats, etc. I >think that these would illustrate the "brand loyalty" trend that you >are considering.
However, consider the following. Orchids have concentrated their pollen in pollinia, in which several million gametes are committed to the thorax of a bug. It matters deeply where the bug goes next. This is much less true for dust pollen plants, where there is a little for everyone, and not all the pollen comes off in the next flower. Orchids therefore have to 'imprint' their pollen-bearer with messages that cause them to seek similar. Or they have to have an extraordinarily specific pollen removal mechanism, such that a bee (say) can visit umpteen flowers before hitting another of the same species, when the gametes are removed and go live. 'Tis one or 'tis t'other. The general level of fixture of stipites to a bugs bum is not in fact very solid, observation suggests. Hence, if orchids are not to die out, the bug needs to go swiftly and surely to another of the same. Question: why would they do this? Answer, provisional and so forth, because they "want" to do so. One can hypothesise how this 'want' is engendered, but given the non-specificity of carrier bug to which my original post referred, it is unlikely to be a specific evolutionary mechanism. Rather, it has to be derived through the use of a toolkit that all bugs have, which helps them to learn which flowers have good nectar and which do not; and so forth. We know that they can learn these things, and in fact do sophisticated things with this information. So, I hypothesise, orchids with their complex and evidently purposeful floral design are in fact hackers of the bug firmware. They call the bugs API - "This_Flower_Shape_Desirable" - without actually delivering anything particularly useful to it: limited or no nectar, some limited wax, no edible pollen. Smart cheapskates. _____________________________________ Oliver Sparrow Tel: UK (0)20 7736 9716 www.chforum.org www.treknepal.org www.trekperu.org www.datafreeze.com _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
