Fly-mimicking weevil (Mnemynurus sp.)

This weevil is a Mullerian mimic of a flesh fly (Sarcophaga spp.). Mullerian mimicry differs from Batesian mimicry (deception of would-be predators through the adoption of similar colouration, morphology or scent of a model species) in that the mimicry results in a propagation of both species' unpalatability. In this case, both the flesh fly, and the fly weevil mimic are agile, and fast. The more 'apparent' flesh flies there are out there, the faster such a 'message' is disseminated amongst predator populations.

 

Animals show preferences for certain food types. This can be based on potential risk (ie. more dangerous prey which risks damaging the predator are only pursued when predator is facing starvation). Or else the amount of energy required to expend to catch prey (ie. sharks preferentially eating seals, for higher energy content, but will also eat other food types). All that is needed for the evolution of a trait is the improvement of 'fitness'. Simplistically, if looking like a fly decreases the weevil's position in the hierarchy of prey preference, then more weevils with the trait survive-->greater fitness-->evolution of trait.

 

Thanks to Henry Hespenheide for the ID.

 

Photo from Mache-Chindul reserve, Ecuador.

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