Re: Archaeopteryx with bird book, was Re: Archaeopteryx flight

[Patrick Norton <ptnorton@suscom-maine.net>]

Tim Williams wrote:

> I think there is good evidence that the naked head and neck is an 
> adaptation to a particular type of scavenging, not just being a scavenger 
> per se.<

Your qualification is a good one.  Getting back to Archie however, let's 
assume (setting aside my own skepticism) that a relationship exists between 
bald-headedness among some large scavenging birds and that this condition is 
related to a specialized type of scavenging behavior.  Under those 
assumptions, we are still left with the facts that: 1) Archie was small 
(relatively); 2) that views about its feeding behavior are almost entirely 
speculative; 3) that there is no evidence for a selection towards 
bald-headedness among extant small scavenging birds and that; 4) the anatomy 
of birds can be expected to result in a  bias against the fossilized 
preservation of contour feathers. Given all that, the simplest 
interpretation of the absence of preserved head feathers on Archie is that 
it is exactly what would be expected in a fossil bird, given the 
preservational conditions.  In my view, the Archie fossils do not support 
the view of some who seem willing to conclude that they demonstrate the 
*absence* of head feathers on Archie and, taking a second jump, that this 
condition is evidence of a scavenging lifestyle.

Pat