Butterfly mimicry through the eyes of bird predators

Date: November 5, 2015

Source: Tata Institute of Fundamental Research

In the natural world, mimicry isn't entertainment; it's a deadly serious game spanning a range of senses -- sight, smell and hearing. Some of the most striking visual mimics are butterflies. Many butterflies become noxious and unpalatable to predators by acquiring chemical defences from plants they ingest as caterpillars. Other butterflies mimic the 'aposematic' or warning colouration and conspicuous wing patterns of these toxic or just plain foul-tasting butterflies.

In a new study, scientists from the National Centre for Biological Sciences (NCBS), Bangalore and the National University of Singapore (NUS) investigate how well butterfly mimics resemble their aposematic models.

Shiyu Su, a PhD student advised by Krushnamegh Kunte from NCBS and Matthew Lim from NUS, investigated mimetic butterfly communities called 'butterfly rings' from the Western Ghats of India. Since butterflies are often eaten by insectivorous birds, her aim was to understand how similar mimics were to their aposematic models when perceived through the eyes of bird predators.

The research, which is published in the November issue of the journal Evolution, reveals some fascinating forces driving the evolution of butterfly wing mimicry. The first result in the study indicates that female butterflies are generally better mimics than males.

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