I'm no researcher But From personal Observation, They have VERY good vison. Yes, From What I've seen, they do see in color. I've even heard of Some igs attacking people when they wear a red shirt, but not when they wear a shirt of any other color. So Exactly HOW good in comparison to Human Vison, I couldn't tell ya. But From My Observations, They have really good eye sight.
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2.0 Iguanas, 2.4 Beardies, 1.2.1 Saharan/Nigerian Uromastyx, 0.0.2 Leos, 0.0.1 African Fat Tail, 1.0 Columbian Rainbow Boa, 0.0.1 Fla Garter Snake, 0.1 eastern garter, 0.0.1 Banded California King Snake (M.I.A.), 0.0.1 Corn Snake, 0.0.3 Fire Belly Toads, 1.0 Eastern Painted Turtle, 0.0.1 African Sideneck, 2 Horses (soon to be three {Baby next May!!!}), 4 cats, 1 dog, and I'm still not done.....