Posted by:
CKing
at Wed Apr 12 18:15:13 2006 [ Report Abuse ] [ Email Message ] [ Show All Posts by CKing ]
>>Hi,
>>
>>I agree with what Wulf wrote.
>>
>>Lesley Rawlings looked at pythonine molecular phylogeny in a PhD at the University of Adelaide and has subsequently published on the Morelia viridis 'complex' and on Liasis. However, the mitochondrial sequences she used turn out not to be adequate for more basal relationships, so most aspects of Kluge's phylogeny have not been tested yet. More molecular work is being done at UofA by Steve Donnellan and students, on the Morelia spilota group and other things.
>>
>>A few years ago I added the Oligocene-Miocene fossil 'Montypythonoides riversleighensis' to Kluge's matrix and found it came out within Morelia,
Monty Python? That is cute, naming a real python after a fictional one. Among dinosaurs, someone named a theropod Bambi-raptor. So, perhaps in the future, we will have a fossil anuran named after Kermit the Frog?
> but did not change other major features of the cladogram (Aspidites still came out basal, even with revised outgroup relationships). I'm suspicious that this implies at least 6 ghost lineages in Australia over the last 25 million years, and it would make more sense of our (albeit meagre) fossil record if Python & Morelia are basal, Liasis (present in early Pliocene), Antaresia (Pleistocene, unpublished) and Aspidites (no fossil record) more derived and recent.
>>
>>-----
>>John D. Scanlon
>>Riversleigh Fossil Centre
>>Outback at Isa
>>Mount Isa, Queensland, Australia
>>riversleigh@outbackatisa.com.au
Hopefully mtDNA evidence will become availabe soon and all this will probably be worked out. I hope, however, that the proper outgroup is chosen in these studies. One DNA study done a few years ago chose a derived descendant of a ratsnake (Lampropeltis) as the "outgroup" to the more basal Old World ratsnakes! That would be like choosing Homo erectus as the "outgroup" when one tries to analyze relationships among the great apes! If an improper outgroup is chosen, the whole effort will be wasted.
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