Here be dragons

See the monitor lizard? It is staring at something. 

Malayan Water Monitor lizard

See the crocodile? It does not like to be stared at. It is showing its displeasure in a very open fashion.

Estuarine Crocodile

This is the same crocodile. It is now facing another direction. Now, what has upset the crocodile?

It is another monitor lizard on the far bank. Giving the crocodile a look of utter boredom. There are more important things in life than sharp teeth.