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Re: birds scales



>Presence of a character in a juvenile is not a good guide to a ancestral
>state (otherwise you would have to assume that the ancestors of humans were
>toothless and the ancestors of dogs had their eyes sealed shut!).

Partially true.  The problem with this analogy is that humans and dogs are born
"unfinished."  They still do a large amount of development after birth.

>Secondly, it is not true that down is found "mostly on chicks".  It is just
>that on chicks there are no normal contour feathers (megapodes excepted?);
>their down is of a special type, called natal down..  A typical contour
>feather is, in addition actually quite downy at the base.  For a famous
>example of adult down consider eiderdown, plucked from the breasts of female
>common eiders to line nests (and comforters, sleeping bags etc.).

To repeat myself, since down is the *first* feather type to appear on a chick,
down should have been the first feather to appear on the group.

Rob

***
"Don't panic!"