Well, the more I work with reptiles, the more I see that there are ranges of intelligence level there as there are in the bird world, and among us humans. Even fish have varying degrees of social behavior, parenting, and intelligence. Ciclids protect their eggs and young until they "fledge" just like birds.
Do you or have you ever kept bearded dragons? OMG, they are very soulful! You know exactly how they feel about you by the look in their eyes. And they have a rudimentary language, a sign language. I have one female who knows the whole language and uses it! She is skittish toward humans because she was mistreated before she came to me as a rescue. I call her my indigenist. LOL!
She has four different head movements, bobs if you will, two or three distinctly different arm waves, and then the smiles. Crack of a smile means "I am feeling timidly social today." Big gaping mouth and mouth stretch or what I call a beardie yawp, after Whitman, means "I am VERY happy!" THen she will stare a hole through you with unmistakeable hatred, meaning "I do not want to be your friend today, so don't touch me!
LOL! The bobs and waves are a bit less obvious, though I have some comical interpretations there.
I want a trio of crockodile skinks. They are the lizards that guard their eggs and young. Here is an article that will amaze you:
http://www.nhm.ac.uk/hosted_sites/ch/ch/2001/2/

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