VAAlbert said:Agreed! Very happy to describe terms.
From Webster's Third New International Dictionary, a gestalt is a "configuration of physical, biological, or psychological phenomena so integrated as to constitute a functional unit with properties not derivable from its parts in summation."
In other words, a general, overall perception that can defy description by a series of explicit attributes. So, with a Phrag, maybe you can tell it is a Phrag by just looking at it, but you can't really say why.
VAAlbert said:Hello again, Guido:
Just some counterpoints; having some fun!
Well, if inflorescence branching isn't constant within Phrag, then it doesn't discriminate Mex and Phrag perfectly -- if a novice compared Phrag caudatum with Paph and Mex based on this character, he might group Mex with Paph. Throw in a branched-inflor. Phrag, and the situation becomes more complicated.
Again, it is true that staminodia of Paphs and Phrags are dissimilar at the gestalt level, but those of Mex and Phrag are not particularly! Again, overlapping suites of characters can make identification -- using keys -- difficult for non-specialists.
Come on now! What about Paph barbigerum or helenae? To be picky, we could even throw in some of the tiny Cyps. True enough, the leaves of Mex show xeromorphic adaptations, as do those of Paph druryi. So, again, we need to say 'very thick-leaved plants that are very small, X cm by X cm'.
These features are mostly in the realm of gestalt! For the first, compare Paph druryi with Mex, for the second, compare Paph hangianum with Phrag kovachii, for the third and fourth, maybe get confused between Paph delenatii and Phrag schlimii. You and I can tell the difference, but a practical system is one that suits multiple users of different backgrounds. *Not that I'm saying we shouldn't have a system with separate Paph, Phrag and Mex* -- only, as the Devil's Advocate, that one genus is an alternative, based on the bulk of the character data that supports a conduplicate-leaved lineage more than it does the specific 3 genera.
I won't grant you the first one in its entirety, Guido. Nobody doing molecular phylogenetics works with entirely unknown groups of plants; i.e., virtually all plants studied have already passed through the alpha phase and (hopefully) have valid names and fall into somebody's classification. Molecular data, as applied to such plant groups, can be very useful in determining whether supposed plant taxa have a single evolutionary origin, or several. The latter was found to be the case with Flacourtiaceae some years back, and after morphological/anatomical investigators took a second look, they found decent characters that support the separate origins. So in this case, molecular phylogenetics helped to redefine a plant family, since the 'true' Flacourtiaceae group could only include those plants related to the type species. Now, the taxonomy of former Flacourtiaceae groups has been changed, and accepted by most taxonomists. For *many* similar examples, please flip through Peter Steven's Angiosperm Phylogeny Website -- http://www.mobot.org/MOBOT/Research/APweb/welcome.html . Of course, similar stories exist within the generic level.
So far as practicality goes, the members of orchid societies don't need to do this work! Results are easily disseminated, and when taxonomy might change as a result, implications for morphological diagnoses can be well elucidated. Who would suggest using direct molecular research to identify that non-blooming Paph plant on your windowsill, just collected (illegally, maybe) in Borneo? Let it bloom first! Then, if it doesn't match other species' descriptions or photos, bring it to the attention of a specialist or two. Then, maybe it'll get described and put into a taxonomic system. Then somebody might want to do molecular work to see what species it might be related to (genetically). Just an example.
OK again, but let's talk about forming a classification that has a key. That's the issue so far as I'm concerned. And remember, I don't object to Mex, Paph, & Phrag -- since they can be keyed out, AND they form separate evolutionary groups! (so long as you are willing to consider a monotypic genus a group)
Come on now! Molecular phylogenetic research has, e.g., cleared up the issue of whether the Paph delenatii group (Parvisepalum, at whatever hierarchical level) is distinct from the Paph concolor group (Brachypetalum/Concoloria). Different taxonomies exist, but this research has shown that the 'parvisepalums' and 'brachys' branch off sequentially from the base of Paph, such that one subgenus or section for both would not constitute a natural group.
And if one gets picky with your usage of the word 'study', molecular research has certainly helped us to understand floral evolution among the slippers. Given that Paphs and Phrags at the base of their respective sub-trees have infolded (and usually inflated) labella, that Mex also does, and that Cyp (for the most part) and Selen also do, one can readily infer that such floral morphologies are 'primitive' within Cypripedioideae. This has consequences when one tries to interpret the gestalt floral similarity between, say, Paph delenatii and Phrag schlimii. Cribb hypothesized parallel evolution based on pollinator similarity, but molecular phylogenetic studies suggest this (basic) similarity to have been derived from shared, primitive characteristics. The Lorifolia Phrags and the vast majority of Paphs are more evolutionarily 'advanced'. Interestingly, the phylogenetic tree strongly suggests that the evolution of fly pollination has occurred several times in parallel among the slipper orchids, from basically bee-pollinated flowers.
You certainly have a 'feeling' for your organisms, but taxonomy (supposedly) should have a scientific basis. According to you too. That means, to me, that you need characters that can be used in keys. I am becoming a broken record here. If we were chatting in a forum on grasses or crucifers instead (e.g.), we'd be *really* concerned with diagnostic criteria that one can actually find written down on paper. But even though we are talking slipper orchids, that does not make these plants immune to the sundry aspects of a good classification: good (useful) circumscriptions around taxa (be they genera, species, etc.), and names with proper priority to match them. Just because a Mex and a given Phrag, a Paph, and a Cyp might be 'diagnosable' by the untrained eye, that doesn't abrogate the need for a formal, keyable, slipper orchid classification. So, why not get off the gestalt thing, and just go for key characters? One can suggest quite fine key chars. for a single conduplicate-leaved genus, or one can make a nice key for Mex, Paph, and Phrag. I suppose keys become more difficult at the slipper species level, however... though some have tried.
Well, parvisepalums aren't a 'link' between cyps and Paph, but being basalmost in Paph, they may have inherited some chars. in common with the common ancestor of Paph, Phrag, and Mex (which I have already described as probably having the inflated pouch character). 'Missing link', no, but both Chen and Cribb made just a little sense when they suggested such things. Not a very good way Chen put it, however.
Evolutionary research = guesswork? That's a funny one!
Finally, glad that you know what the 'related species are' when you see a plant, but I'm not even sure what a slipper orchid species is!
Best as always
OK enough informally, but one should still be able to key it out formally! And in this case, this should pose no problem so long as one defines Oncidiinae first with key characters.Braem said:Victor,
1) flower looking like a bee .... Hispaniella henekenii
there is no other plant in the Oncidiinae that matches that other than Hispaniella. So where is the problem?
Ah, I think we may have been 'talking past each other'! Do you mean the evolution of orchids in the sense of their origins from monocotyledonous ancestors? The actual evolutionary steps that took place millions of years ago? The actual morphological changes, i.e., that occurred? I have mainly been speaking about evolution in terms of reconstructing the history of orchid lineages, i.e., phylogenetics. We do indeed have tools from (probably especially molecular) developmental biology that can HELP us to try to reconstruct how morphologies may have evolved in the past, but these will only generate hypotheses, maybe strong and very interesting ones, but only hypotheses. There is, as you say, nothing in the fossil record that can give us any direct evidence. So, e.g., the hypotheses about inflated pouches = primitive in slippers from my earlier posts i a hypothesis that matches both the phylogeny and a look at how flower buds develop.Now to my funny statement: can you please give me one piece of single evidence that is reliable (fossil record, or whatever) enough to allow a decent statement about the evolution of orchids. Maybe I missed something somewhere. And if so, I would be glad to be shown that I did miss something
VAAlbert said:Ah, I think we may have been 'talking past each other'! Do you mean the evolution of orchids in the sense of their origins from monocotyledonous ancestors? The actual evolutionary steps that took place millions of years ago? The actual morphological changes, i.e., that occurred? I have mainly been speaking about evolution in terms of reconstructing the history of orchid lineages, i.e., phylogenetics. We do indeed have tools from (probably especially molecular) developmental biology that can HELP us to try to reconstruct how morphologies may have evolved in the past, but these will only generate hypotheses, maybe strong and very interesting ones, but only hypotheses. There is, as you say, nothing in the fossil record that can give us any direct evidence. So, e.g., the hypotheses about inflated pouches = primitive in slippers from my earlier posts i a hypothesis that matches both the phylogeny and a look at how flower buds develop.
Hope this helps.
yes. It seems to be the case. The problems I have are (for example): what is the proof that low chromosome counts are the primitive form? or where is the proof that inflated pouches are primitive? or that the single-flowered species are promitive etc. or vice-versa
The phylogenetics are indeed the interesting part. I remember a paper from the late Jack Fowlie on the evolution of the slippers and Wallace's line in the Orchid Digest, for example. Jack was a great guy, but ...
So what I mean is: where is the proof that cyps or more primitive than paphs or phrags or vice versa.
VAAlbert said:Hi Guido,
... In the case of evolutionary biology, we cannot seek proof ....
gore42 said:Dr Braem,
I think that this statement is in accord with most post-positivist science methodology. The general idea is that scientists can provide support for certain theories, and dis-prove alternative theories, but not prove theories to be true. This is a well accepted position within science and the philosophy of science.
- Matthew Gore
In response to this statement, you have called into question the requirements of justification for his claims, making this an epistemic issue. As such, it is proper to answer the question from the standpoint of Philosophy of Science.Hi Guido,
... In the case of evolutionary biology, we cannot seek proof ....
gore42 said:Dr Braem,
I agree that sceintists are responsible for explaining and supporting their conclusions, and I am making no claim at all regarding the validity of Victor Albert's work.
In response to this statement, you have called into question the requirements of justification for his claims, making this an epistemic issue. As such, it is proper to answer the question from the standpoint of Philosophy of Science.
As I say, this only places different requirements on what Dr? Albert must provide as justification. Science does not require that he provide proof (in the logical or geometrical sense) for his proposition. Obviously, this doesn't mean that his proposition requires no justification... and I don't know whether he has provided what is required or not, as I haven't read his publications.
- Matthew Gore
Well, I'm glad we took a break with this one. Never hid a thing, will still be happy to chat, but will not engage in phantasmagoric argumentation! :rollhappy:If Victor Albert refuses to do that, the question that should be asked is: "What has ge got to hide?