Dragons in particular are known for their systems of visual communication between each other. Apart from breeding colours, this can involve a wide range of physical movements. Such movements can include head bobbing, arm lifting and dropping, arm waving, body posturing, inflation of the throat area, change of colour of part or all, lifting of the tail, flicking of the tail, moth gaping, tongue flicking, substrate licking and a few more. In addition, the meaning can be dependent on who goes first and how quickly the action is performed. In a study of bearded dragons the researchers came up with around 50 different differing signals each with its own meaning. Although I have searched, unfortunately I cannot find the article.
I am aware of two instances where youngish Eastern Water Dragons were in visual line of sight to a dominant Eastern Bearded Dragon. Both Water Dragons died and a veterinary assessment was they appeared to have died of stress. It appears that they understand at least some of each other’s visual signals... which is very interesting.
Try Googling on EWD visual communication – I came up with two possibilities.
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