phylogenetic taxonomy

[Its_a_friday]

Could some1 shed some light on this subject? I have been wondering ... which nepenthes species split off from another? Which nepenthes is the most distantly and most closely related to the ancestor?

 

[xvart]

Talk about opening a can of worms... lol. I pretty sure I saw a loose phylogenic tree once. Actually it may have been of Drosera... PhissionKorps may know what I'm talking about...

xvart.

edit: Nevermind, this is what I was thinking of: Drosera tree.

 

[phissionkorps]

Could some1 shed some light on this subject?

In what sense? Way too broad of a topic to just go off on. You seem to know what they're used for. You should look into trying to get a copy of Jebb and Cheek's skeletal revision of Nepenthes. It's in either edition 41 or 47 of Blumea.

I don't think any two people actually agree on the phylogeny of Nepenthes, or even what is most closely related to what if say, looking at 1 monophyletic group of only a few taxa. Lots of people have ideas, and think this and think that based on only morphology. Basing taxonomy solely on morphology is a great idea....if you're Linneaus. Otherwise, it's stupid. For some reason, even though the technology has been around since the 80s, no one has ever done phylogenetics on Nepenthes AFAIK. There was/is a paper that was recently/is about to be published by I think Dr. Mullins that has to do with phylogenetics (based on chloroplast trnL-F, and nuclear 5S-NTS sequences). I haven't seen it, but I think it is basically useless in a phylogenetic sense. Dave Evans explained it rather well in a post from a few months ago:

Hmm, okay I think for discussion this is good, but we will not be able to arrive at solid numbers until comprehensive genetic research is actually done. Basically all that is being done is comparing the spelling of a couple snippets of DNA for differences. Have any alelles even been identified? No. (At least, not that I'm aware of) Genetic testing and understanding how DNA works are not really the same thing. While we can easily compare relationships between individuals and groups, by comparing random mutations, we can't actually read the DNA and directly understand what it translates into. Which genes on which of the 80 chromosomes are responsible for spelling out the differences that generate the peristome we see on Nepenthes tentaculata vs the peristome of N. hamata? And which alleles control the overall hairiness an individual displays? Clueless? Me too...

How many genes are basically the same in all species? No idea? Well, then it is currently impossible to say where to draw the line between complex hybrid vs. species based on the DNA an individual has acquired. Also, some groups of Nepenthes might tend to share more of their DNA than other groups.

IMO, until someone does a GOOD analysis of Nepenthes genomes, then constructs a tree using microsatellite data, then uses some hardcore bootstrapping, all phylogenetic trees for the genus are worthless crap.