More to chameleons than social signalling

Strange that humans who are not trustworthy, inconsistent with unsavoury qualities are still being compared to chameleons when these humans can survive in very toxic environments whilst chameleons cannot. 

After removing toxic substances from the surroundings over a period of three years, an observation: to have gardens with chameleons avoiding use of pesticides and growing shrubs for them to climb on helps. Also chameleon friendly gardens attract butterflies, bees,dragonflies,frogs...

Did Charles Darwin mention anywhere that chameleons are least stressed when they are green in colour?

There is more to chameleons than social signalling. Their presence could indicate a bio diverse environment.

  A resident chameleon climbing up a vine...mindfulness