United States of Lizardia

[Bruno]

Originally Posted by oldgringo2001

"Motion-based" sight is a crock from the first Jurassic Park film, and the oversized velociraptors in all the films are never depicted as having limited vision.

lwcamp isn't talking about Jurassic Park and ridiculous frog DNA splicing stories, he's talking about rods and cones in real animals. Also, that particular tidbit isn't new from the film, it dates back to the book. The raptors in the book didn't have that problem either - each "dinosaur" was a unique mishmash of DNA and some got problems that others didn't.

Originally Posted by oldgringo2001

But cats also have great night vision and they can see color, which gives them more opportunities to spot prey in the daytime.

Cats, like other carnivores, see only two colours, not three. And like other carnivores cats "see" colour but are only really vaguely aware of colour, lacking most of the neurological hardware needed to do anything sophisticated with it. They use two different kinds of colour in order to improve the quality of the rather wuzzy image they're receiving, not to check what colour anything is. They can be trained to actually recognize/pay attention to colour, but it's a bit difficult.

Originally Posted by oldgringo2001

Also, colorblindness is far more common among human males than females; whatever worked to produce this anomaly would probably duplicate it on a world with an amazingly similar history and culture to present-day (human) Earth.

It's more common among human males than human females because the genes for full colour vision are on the X chromosome, and not on the Y. Reptiles and birds don't even have an X OR Y chromosome. It's not clear where on the some-reptile/most-bird continuum dinosaurs sit with respect to sex determination, but it's entirely possible Lizardians are one of the (many) species where sex is determined by factors either utterly unrelated to genetics, or only partly related to genetics. This is possible even if they're more "birdlike" - at least one bird still uses the temperature-at-incubation-based system.

If they're instead on something like the majority bird scheme, then it's the males that have the full chromosome pair (ZZ) and the females that have the stunted mismatched pair (ZW in birds).

And to top things off, the Z chromosone does not carry the genes for colour vision in birds, it's basically completely unrelated to the XY system.

Colour vision is on the X chromosone in mammals mostly because modern mammals just happen to have promoted a perfectly innocent normal chromosome to sex-selection duty that had the colour vision genes on it (birds picked another unrelated one - probably the major criteria in both systems was that it wasn't doing really dangerously fundemental developmental stuff at the time)