The cunning (and conning) cuttlefish

“The old adage that cheaters never prosper is far from applicable in the animal kingdom.”  That’s the first sentence of a new paper by Brown et al. that was published this week in the journal Biology Letters.  There are numerous examples of animals deceiving other members of their own species and social group.  For instance, one animal could give a false predator alert signal to its group, so it can have a resource all to itself.  However, these cheaters run the risk of being discovered and beat up or otherwise punished (humans do this too but we usually put our cheaters in jail).  The authors investigated this process of deception in the world of cuttlefish.

Cuttlefish are cephalopods like the octopus. They can change the pattern and texture of their skin very rapidly, and different patterns act as signals to their fellow cuttlefish.  Females have one specific display towards rival males ("go away"), whereas males have another pattern when trying to court a female.  Males are often competing for receptive females and interrupting each other’s courtship attempts (that’s not cool).  So wouldn’t it be really beneficial for a male if he could change his display so as not to attract another male rival during courtship.

The authors witnessed an amazing act of signal deception: a male that is interested in courting a female to his left would show the courtship pattern on the left side of his body, while simultaneously showing the female signal to his right side.  A rival male coming up on his right side would see the female display saying “get out of here”, so he wouldn’t try to interrupt the courtship process. 

From Brown et al., 2012, Biology Letters

Just look at this image here; the male has stripes on the side facing the female (“come on baby”) and spots on the side facing a rival male (“not interested”).  And the amazing thing is that they only witnessed this particular type of patterning on males in the company of a receptive female and a rival male.  There’s no sense in cheating if there’s no male around and if there is more than one rival, chances are the trick will be discovered and the cheater will get punished.

Molecularly this is blowing my mind -- how can they create such intricate patterns so quickly?  Behaviorally this is also incredible – it’s such an intelligent form of cheating and it will really pay off if it means he can have a successful mating and pass on his genetic material to the next generation.