Cleaner wrasse are a type of fish whose primary job is to provide a service to larger fish, in the form of eating the dead skin off their mouths! Through some creative research methods, scientists have discovered that cleaner wrasses will “cheat” ( by eating the protective mucous off a fishes mouth rather than the dead skin) if they believe their partner wrasse isn’t watching! Eating off protective mucous in the fish world is a major breech of etiquette that can put the cleaner duo out of their job (that literally puts food in their mouth), so to “cheat” they need enough awareness of what their partner is doing to know when to snag some extra food!

Sketch & fact by Karli Chudeau

Reference: McAuliffe, K., Drayton, L. A., Royka, A., Aellen, M., Santos, L. R., & Bshary, R. (2021). Cleaner fish are sensitive to what their partners can and cannot see. Communications biology, 4(1), 1-7.

[Edited by Isabelle McDonald]