With males normally display pulsating stripes, and females mottled, the Mourning Cuttlefish (Sepia plangon) is already a unique looking species. However, this cuttlefish goes a step further in its use of variable patterning.
Observing wild cuttlefish in Sydney harbour for six years Culum Brown of Macquarie University in Sydney and his team noticed that whenever a male was courting a female, and there was a rival male nearby, the courting male started ‘lying’. He displayed male colours on the side facing the female, but female colours on the other side to dupe the rival and prevent him from interfering.
Males did not do this when there were two rivals present, presumably because it would be too difficult to deceive both of them. That suggests the animals were trying to avoid being caught out!