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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.