|MadSci Network: Evolution|
Looking at ediacaran organism's staggered symmetry, a thought arose in me, then an intuition. Looking at staggered symmetry arrangements, you can make a comb like structure with a spine by alternating each segment between a spine segment and a tooth segment. This comb like structure can be rolled up, radially, into wheel where the teeth radiate outward and the spine segments combine together in the center as a hub, or the spine segments can serve as pivots that grow a tooth on one side, and then an inverted pivot that grows a tooth on the other, creating a bilaterally symmetric structure. I've drawn a picture here: http://imageshack.us/photo/my-images/507/symmetry.png/ . How good is this intuition, and what are the problems with it?
Re: A comb as common ancestor for bilateralia and radiata?
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