[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: epidermal structures.
Alan Brush wrote:
<<we have become sloppy with some important definitions>>
Sorry Alan, I was just trying to emphasize the possible commonality of many
pelage-like things. Fortunately for us all, I'm probably the only one (at
present) who thinks feathers and teeth have anything in common.
<< One significant difference between feathers and scales is that feathers
are tubular and scales are planer. The surfaces are probably not homologous.
There is no evidence that scales are transformed into feathers or that
feathers are transformed into scales. >>
Though I know your ornithological knowledge is extensive, I think you may
have missed a detail. I recall having seen photographs of bird scales that
have feathery tips. I don't recall which species, but I think it may have
been an arctic owl. Given such half-scale half-feather entities, it becomes
obvious that somehow the two must share a common ancestral structure, and the
tubular and planar structures are interconvertable. These days, I'm starting
to suspect the tubular, pointy structure came first, then flattened later to
yield scales. Why not?
Thomas P. Hopp
Author of DINOSAUR WARS, a science fiction novel published by iUniverse
Now Humans are the Endangered Species! http://members.aol.com/dinosaurwars