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VOL. XXII NO. 5, June 16-31, 2012
Butterfly tricks
By Pranav Balasubramaniam

Butterflies have never really been particularly shy members of the natural world. As they flutter by, flaunting their vibrant and sometimes downright outrageous hues, overlooking them often proves to be exceedingly difficult – nearly impossible. And once sighted, turning away from the magnificent show-offs becomes a task fraught with an arduousness of even greater proportions. It should come as no surprise, then, that these scaly winged day-fliers were the first invertebrates to tickle the human being's fancy... and not in a particularly non-invasive way either. The only specialist equipment that a hobbyist required was a net and a misplaced sense of wall decoration. After all, these 'objects of art' were fairly abundant, and pretty easy to net (especially during specific times of the day – late mornings, for example). And if middle-aged blokes with nets could do it, it should be a real breeze for a predator, right?

Wrong. Innocuous though they may seem, in reality butterflies have some surprising tricks up their sleeves. Be assured, there are two very different sides to this coin – quite literally – a radiantly coloured upper-side coupled with a dull, prosaic underside, permits a butterfly to selectively attract, to assume different wing positions with varying levels of conspicuousness; a useful trait, no doubt, but not nearly as effective a predator deterrent as most would hope for.

A few butterfly lineages have taken that next step, by evolving eyespots, a curious representation of vertebrate eyes, on their wings. For a long time, scientists were unsure of the exact purpose that these served, leading to an abundance of hypotheses, from auto-mimicry to intimidation and predators, especially the smaller insectivorous birds (an experiment involving Great tits and Junonia butterflies – Kodadaramalah, 2009).

Now, most butterflies have extremely tight schedules. What with the most frugal lifespans and very fixed objectives (nourishment, reproduction), it is but natural that they should exhibit what they do best at least twice a year, which is why many species dress for the occasion, always sporting the latest trends in pigmentation.

Seasonal polyphenism (the term for the phenomenon described above) expresses itself in multiple 'forms', often greatly confusing a novice to butterfly identification. It is currently believed that such variable pigmentation provides appropriate camouflage throughout the season – another handy antipredatory mechanism.

Anti-predatory drills begin at a tender age – butterflies in their early stages exhibit many ways of cleverly blending in with their surroundings.

Butterflies may be, in more ways than one, masters of disguise and concealment, but this is certainly not life insurance of any sort. Would invulnerability be a realistic possibility? – (Courtesy: The Bulletin of the Madras Naturalists' Society.)

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In this issue

Welcome restoration approach by Government
Garbage collection plans go awry again
Looking back
Driving Down Memory Lane
Masters of 20th Century Madras science
Three looks at heritage
There's heritage in idlis & sundal
The plight and the challenge
More Iyengars of cricket
Butterfly tricks

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Short 'N' Snappy
a-Musing
Our Readers Write
Quizzin' with Ram'nan

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