Bob Bales has claimed that no one has refuted the points that
he has made about how scales could have evolved into feathers.
I find this puzzling, since I posted this to the net, from
the same city, with his name prominently featured in the
subject line.

Bob, this is a refutation of your claim that feathers and
scales arise from different skin layers. Please retract the
claim above.

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Bob Bales claimed a few weeks ago  that  bird  feathers  and
lizard  scales  'came  from different skin layers' and hence
feathers could not have evolved from scales.  Unfortunately,
that  does not match up with the data I have here before me:
(detailed reference at end of article) - perhaps  you  could
supply me with a more detailed reference for your assertion?

	  "Skin consists of two layers, a  superficial  epidermis
	  derived  from the embryonic ectoderm, and an underlying
	  dermis derived from mesoderm. The development of scales
	  or other epidermal structures depends on inductive sig-
	  nals from the dermis." - pg 160

In other words, both grow from the epidermis, under the con-
trol  of  chemical  signals  from  the  dermis.  Here is the
interesting part: By grafting  lizard  epidermis  over  over
chick  and  mice  dermis,  the scales can be made to grow in
patterns corresponding to chick  feathers,  and  mouse  fur,
even  mouse  whiskers - the code for the actual structure of
hair and feather is not there, but the embryonic  signalling
system is so similar that:

	  "Lizard epidermis  responds  to  chick  tarsometatarsal
	  dermis  to  produce  large  scales indistinguishable in
	  appearance and arrangement from  chick  tarsometatarsal
	  scales.  Lizard  epidermis  responds  to  chick  dorsal
	  dermis, which in chicks determines the arrangement  and
	  morphology  of  feathers.  However, lizard epidermis is
	  unable to interpret the specific  signals  for  feather
	  morphogenesis.    Instead,   the   epidermis   produces
	  arrested scales arranged in a typical hexagonal feather
	  pattern.  In  a  like manner, lizard epidermis combined
	  with mouse dermis forms not hair, but  abortive  scales
	  arranged in typical mouse hair patterns..." [page 162]

So: not only are feathers and fur coming from the same layer
of  skin, they respond to the SAME DEVELOPMENTAL CONTROLS in
the embryo. What a coincidence.

		  Regards,
					 Max G. Webb

_Embryos, Genes, and Evolution_, Rudolf Raff and Thomas Kaufman,
(c) 1983 Rudolf Raff and Thomas Kaufman, Macmillan Publishing Company.