[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

SCRIPT ON DINO FEATHERS



Hello everyone. David Portree writes:

> Specifically, does Sinosauropteryx lend credence to the widespread notion 
> that they might've been brightly colored like modern birds (for example, 
> toucans and cardinals)?

No, the discovery of feathers in a non-avian dinosaur (whether _Sinosauropteryx_
is truly feathered or not) is totally irrelevant to the possibility of bright
colouration in dinosaurs. 

First of all, the evidence that some dinosaurs may have been brightly coloured
comes from lines of evidence other than integument: the fact that they've got
big eyes, colour vision, and a brain designed with visual acuity in mind ('scuse
the pun). The extant phylogenetic bracket can be used: dinosaurs are most like
living birds, many of which use bright colour in display and camouflage. On the
other end of the scale, living crocodiles are generally dull in colour, but
they are amphibious so are not comparable. Other terrestrial diapsids,
particularly lizards, can be ridiculously brightly coloured, even near
fluorescent. Furthermore, visual display surfaces are moderately common in
dinosaurs (e.g. cranial crests, horns, bosses, armour plates, dermal frills,
tall neural spines), and in view of both the evidence for visual acuity _and_
the extant phylogenetic bracket, it is conceivable and likely that such
structures were employed in colourful display.

Which dinosaurs wore bright colours and which didn't is presently based on
nothing more than logic. While all birds and all lizards may have the capacity
to both sport and be aware of bright, pretty colours, they are not by necessity
all flush in pink, yellow and blue (contra Bakker:)). Maybe grassland (sensu
lato) dinosaurs who had to watch out for nasty predators were dull coloured like
grassland birds and lizards. Take your pick, as long as it makes biological
sense. And as feathers can be grey or brown as well as cardinal-red or peacock-
blue, they can also be partridge-brown or owl-grey. The possible presence of
feathers on _Sinosauropteryx_ (or any other dinosaur) do not tell us anything
about colouration in life.

Hope that helps.

"Careful Dad, he might gore you"
"Heeeeey, you're riiiight - he _does_ look like Al Gore"

"Hey, look! There's a _new_ Mexico!"

DARREN NAISH
dwn194@soton.ac.uk