No idea
by Moraelin (679338)

Well, if you look at nodern carnivores, you see such examples as:

- the fox, which is pretty darn red

- the tiger, which is relatively bright orange and with stripes too (and cats somewhat inherited that: a normal tabby male is almost always orange, though the females are nearly always grey when they're tabby.)

In fact, think about this: the most logical camouflage colour would be green, right? That's the colour we dress our soldiers in, right? Well, in practice mammals are coloured anything but green.

A hypothesis there is that camouflage doesn't always mean having the same colour as the surroundings. Three quarters of camouflage in the animal world seems to have to do more with the mental capacity of your opponent (prey or predator, as the case may be) than with blending in.

Primates have very evolved, arguably top-of-the-line image analysis and recognition capabilities. A lot of more primitive animals don't. For example, strange as it may seem to you, a lot of animals have trouble recognizing a snake as a snake. (In fact, one hypothesis is that a lot of the natural selection pressure for increasingly bigger brains in primates was... snake recognition.) A lot take "shortcuts" to save neurons, like mainly processing edges instead of whole shapes, or mainly seeing stuff that moves instead of analyzing the whole picture. A lot are nearly colour-blind, or have other primary colours for their vision than humans have. Some species (e.g., a lot of birds) don't even try to recognize another animal as a whole, but just look at where the eyes are: both in front for stereoscopic vision means predator, eyes on the sides means harmless herbivore. Etc.

So basically don't assume that what's piss-poor camouflage for _you_, also counts as such for another species. It may be actually _excellent_ camouflage in the environment that animal has to deal with.

E.g., lots of stripes and dots may look like begging for attention to you, but may severely overload the edge detection in more primitive species, by creating lots and lots and lots of extra edges, and thus prevent them from figuring out the whole.

E.g., the reason a lot of exotic fish are orange, yellow and red, is because those frequencies get absorbe the fastest in water. If you go deep enough, pretty much all available light is... blue. So you don't really need to colour yourself black, you only need to absorb blue. A simpler and cheaper to produce pigment can serve the same purpose and achieve the same effect.

E.g., a big tail like that of the pheasant may look like an unexplainable handicap, until you realize that most animals have a very simplified way of judging how big an opponent is. They only judge how big the image looks, not try to reconstruct the 3D animal in their brain and judge the size that way. There's a reason cats puff up and turn sideways when they might need to fight. To _you_ it's the same cat turned sideways, but to more simple-brained animals (apparently including other cats) it just became a lot larger and thus more dangerous. Or to the same animal you might look like a lot of an easier prey if you crouch or sit than if you stand up. So, depending on what predators it had to evolve with, being able to fan a giant tail can actually act as a deterrent.

So basically, we probably can't extrapolate what the raptors' plumage looked like. It probably depends a lot on the environment, and on how their prey's brain worked. And given the many millions of years involved, I wouldn't be surprised if it changed over time as their environment and prey evolved.