Opabinia

[Bill Shear]

Ken, how about sharing some of the evidence for your various
hypotheses?  You invite criticism but that is hard to provide without
knowing why you came to the conclusions you did.

One thing to think about is this--if O. is a juvenile of A., there
should be some intermediate growth stages around.  Both are fairly
rare, so these could be hard to find, but given mortality through
time, there should be a lot more Opabinia than Anomalocaris if the
former is the young of the latter.  Assuming of course that the
chances of preservation are roughly equal at all stages of the life
cycle.  No such intermediate stages have ever been found.  I don't
know if the Burgess Shale has yielded more of one or the other.

If Opabinia is the dwarf male of Anomalocaris, then Opabinia should
be found wherever Anomalocaris occurs.  I don't think Opabinia has
been found anywhere else but the Burgess Shale (could be wrong),
while Anomalocaris has turned up at numerous sites around the world,
most notably and abundantly in China.
--

Bill Shear
Department of Biology
Hampden-Sydney College
Hampden-Sydney VA 23943
(804)223-6172
FAX (804)223-6374
email<wshear at email.hsc.edu>
Moderating e-lists:
Coleus at http://groups.yahoo.com/group/coleus
Opiliones at http://groups.yahoo.com/group/opiliones
Myriapod at http://groups.yahoo.com/group/myriapod