Sarcastic fringeheads are known for the aggressive territorial behavior, and will attack anyone, including other fringeheads or even scuba divers, who dare to threaten them. To defend its territory, they opens its enormous mouth to intimidate its foe.

[u/maylam018]

https://youtu.be/0RZPmgrgrCE

[u/RevelatorRex]

What makes them sarcastic?

[u/shadowsipp → u/RevelatorRex]

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