James: At this point we should probably "agree to disagree". However, I'd like to respond to your last post and I'll leave the field to you. (If you would like to continue through PM's, that would be OK. We have seriously hijacked this thread.)
I have a couple of points. Yes, "happy juice" is produced by osmotic pressure. As a result of my former occupation, though, I'm as interested in the "why" as the "how." Orchids are notorious metabolic sluggards. Why is it that some of them are "willing" (again, an anthropomorphism) to waste copious amounts of sugar in happy juice when logically it would be so precious to them? And why is so much of it released at the flowers? As far as I know, orchids don't even use nectar in their flowers to attract pollinators. As for relieving osmotic pressure, most of the plants in my garden reduce osmotic pressure through special pores on the leaves. And that liquid contains little or no sugar. Any extra sugar is converted to complex sugars and stored or used to build tissue (i,e., cell walls) It seems to me that the "willingness" of orchids to lose so much of this precious resource is an evolutionary response.
Which leads me to my second point. Your response has a contradiction. You said: ..."ants don't guard their sources of nectar..." and, then, in the next sentence you say: "They do, however, protect their herd of aphids..." To an ant, what is an aphid other than a source of nectar. So you're saying, in effect, that ants do protect their nectar sources. Is there any difference between what ants do when they vigorously defend their sources of "happy juice" and when they vigorously defend their aphid herd? If there is a difference, it's not obvious to me.
Finally, this relationship between ants, happy juice and orchids is, in my opinion, a relatively simple relationship. Ants and orchids have evolved an array of relationships that are even more interesting and complicated. Examples would include the pollination strategies of the slipper orchids and the relationship between ants and Coryanthes.
wuness
Last edited by wuness; 02-05-2014 at 08:23 PM..
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