|
Following the recent on-list debate surrounding the
colouration and function of speculated dinosaur plumage, I've taken to looking
at my tatty old book on some european birds of prey. I noticed that all
the birds' feathers (with the possible exception of Pernis aviporus, the honey
buzzard) were of the following colours:
1. Black
2. White
3. Grey-scale
4. Anywhere within the brown
spectrum between peach and terra-cotta
These are not exactly vivid colours. It was
interesting to note that any with bright colour had it in their eyes or on their
skin, not their plumage(specifically their feet and
cere). The following colours were noted on the skin:
1. Yellow - most common.
Token example Accipiter nissus (sparrowhawk)
2. Pink - ranges from subtle
human skin colour with Gyps fulvus (griffon vulture) to more
"mother-of-the-bride" shades, ie, Falco vespertinus (red-footed
falcon)
3. Grey - not the brightest of
things to be sure. Found in Elanoides forficatus (swallow-tailed kite)
among others.
4. Orange? - Neophron percnoterus
(Egyptian vulture) picture is a little unclear, could be a solarised
yellow.
5. Blue! - the cere of Aegypius
monachus (European Black vulture). I also recall (from memory, so beware!)
seeing a raptor with blue feet.
In addition to these observations, I remember red
skin and I think purple? in a couple of other raptors (anyone have any ideas
what these were? is there a predatory bird expert in the house?).
So, the overall trend with at least modern feathered archosaurs is for
camouflage colours using pattern for display on the plumage and actual vivid
colours when present on the skin.
Bearing in mind the hand of
speculation is looming large, and heeding the cautions about using modern
animals to compare to ancient ones - does this bode well at all for more
colourful featherless theropods? (picture if you will a Daspletosaurus with
blue legs)
Sam
|