Why do zebras have their distinctive stripes? No seriously...why would
evolution endow zebras with such an obvious pattern that provides next to no
camouflage in the African savannahs? The question puzzled even our most
celebrated biologist, Charles Darwin, who commented, “The zebra is
conspicuously striped, and stripes on the open plains of South Africa cannot
afford any protection.”
Even to modern day biologists, the question has been perplexing. Perhaps
the stripes are a way the females choose their mate? Possibly – many male
members of the animal kingdom have bizarre decorations such as brightly coloured
plumage or heavy, unwieldy horns that are a clear disadvantage in survival but
serve to attract the opposite sex – but that wouldn’t explain why the female
zebras also have stripes.
Some animals use patterns and bright colours to act as warnings or camouflage–
Researchers have found that when zebra herds move together, their stripes act
as a large optical illusion. Any potential predator is momentarily confused,
giving the zebras vital seconds to escape their clutches.
However, a group of scientists from Eötvös University in Hungary have
found another solution, which is far less glamorous. It seems that the zebra’s
intricate barcode pattern acts as one large insect repellent – in particular
against horseflies. They found that horseflies are quite particular about where
they land to prey. The narrow stripes on the zebra act to break up the hide and
alter how the light is reflected off of it. These two factors make the zebra
less appealing to the horsefly.
It seems remarkable how evolution can be defined by even the smallest of
creatures and how a large creature’s body image can be influenced by a fly no
larger than a thimble.
Author - Rishi Ramaesh
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