Insect phylogeny

[Jim Mason]

Here's one for the systematics folks to chew on.
 
What is the currently accepted version of the phylogeny of the insects and
what is the evidence for it?  Has the fossil record been elucidated very
much or is it all based on assuming that any insect with an aquatic larval
form is more primitive than one with a terrestrial larval form?
 
This may be too broad for the Leps list, so if someone can suggest an
entomology forum for this posting, feel free.  I am interested to find out
what has guided the determination that Scorpion Flies are "more advanced"
than Beetles, why are Fleas considered to be at the top of the heap, etc.
 
Jim Mason, Naturalist
jmason at ink.org
(316) 683-5499 x103
Great Plains Nature Center
6232 E. 29th St. N.
Wichita, KS 67220-2200
http://www.gpnc.org