Roadrunners' built-in goggles

Greater Roadrunner

Roadrunners often run through some pretty dirty and dusty environments.  Plus, they usually bash their prey repeatedly against something hard to soften it up before eating it. Both activities raise a lot of dust/debris.

So Roadrunners (sometimes called chaparrals) have thin, transparent membranes for the eyes, which they can lower to protect their eyes - sort of like goggles. They can also be used to keep eyes from drying out when the day gets unusually hot.

Greater Roadrunner

The coloring of a hummingbird comes mostly from the density of its feathers and the angle of the sun, not from pigment. These things determine how light is reflected off the feathers, displaying a certain color - or not. That's why a Ruby-throated Hummingbird's throat ("gorget") may appear ruby-red sometimes, and sometimes black.

As it moves around the coloring will change. But don't expect it to move around frequently. A hummingbird spends as much as 80% of its time simply sitting on a perch, surveying the landscape.

Broad-tailed Hummingbird