I'm an iguana owner, but many people I've talked to seem to think lizards don't have feelings, and don't show affection. Here is a video I saw posted during a reptile chat. As tegu owners, I think you'll enjoy it. I would get a Tegu, but I don't think our iguana would get along with it.
Tegu attention

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Lamar, Debbie, Nathaniel and Iggi :>~