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New Selenipedium species described.

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naoki

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Oops, you are right, Rob! I screwed up when I was making the ascii tree. Thanks for the correction.

The new world vs old world distribution of this group is kind of interesting. I don't know much about large scale biogeography, but my friend says that there appear to be a bias in plants: Asia -> America is more common than the other direction.
 

PaphMadMan

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LOL, we should do a joint research!

btw, This new species has 3 characteristics that are considered more "primitive":
- having 3 petals (and no pouch)
- having 3 anthers (instead of two)
- having 3 sepals (rather than a dorsal sepal and a fused synsepal)

The chance of having 3 reversed mutations i.e going back to it's ancestral type seem very small and unlikely. I learned early on that if you have two hypotheses that the most simple one, is often (but not always) correct.

Our hypotheses are:

#1 ancestral type which had 3 anthers, no pouch, and 3 sepals evolved into a species with a pouch, two anthers, and a synsepal. This species evolved again into the species Selenipedium chironianum which had reverted back to not having a pouch, having 3 anthers, and 3 sepals.

# 2 ancestral type evolved into Selenipedium chironianum, still having 3 anthers, no pouch, and 3 sepals.

To me Hypothesis #2 seems the most simple and most likely one.

So, the question is how do we prove Hypothesis #1 is correct or Hypothesis # 2 is correct?



Robert
Except, it is quite possible that all those characters share some developmental cue. These changes work together to adapt the flower for a specialized pollination strategy. There's no reason to think they evolved independently. Disrupt one gene and the whole developmental sequence to differentiate the flower from the primitive form may collapse. That is the simplest hypothesis, since orchid floral morphology predates the genus Selenipedium. All members of the genus share a common ancestor that either evolved from something like a Cypripedium or some more primitive orchid that already had the differentiated flower, unless you are proposing Selenipedium as the ancestral genus for all orchids.
 

dodidoki

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Very interesting. Selenipedium "lindenii"... :)
 

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