The university of life

Why Tigers have stripes

Recently we were browsing the net and our eye fell upon an interesting article. It tried to answer the question why lions look fatter than tigers. The author suggested that tigers look thinner because they have vertical stripes. Vertical stripes make you look thin and horizontal stripes make you look fat. This is a well known theory originating in the world of fashion.

In itself this whole argument looks almost ridiculous but we propose that there is an evolutionary explanation for all this. It is often claimed that the stripes of a tiger somehow camouflages him from his prey. This whole notion falls apart when you realize that the worst enemy of a tiger lies not in the visual realm, but in the treacherous world of smells. During a hunting expedition a tiger always makes sure he is downwind of the prey. Body odour is his worst enemy, like with many of our fine young people nowadays spending too much time behind computers in sticky hot rooms.

We propose a different evolutionary explanation for the stripes of a tiger. It is not about camouflage, although this might have been a beneficial side effect. The tiger hunts in forests with dense undergrowth. The tiger is also one of the largest cat species. Naturally it would be difficult for a fat tiger to traverse the thick jungle. Tigers therefore have to be thin, and are therefore relatively thinner than plain dwelling lions. But how does this explain the stripes of a tiger?

It is the phenomenon of evolutionary trickery. At one point in the evolutionary history of the tiger some specimens started to appear with some vertical stripes due to some mutation. Potential mates were tricked by the illusionary effect of vertical stripes into thinking they were dealing with a thinner mate than he or she really was. Selection favoured the cheaters of the tiger kingdom. More and more stripes appeared until we finally arrived at the current tiger. A thin big-cat, who looks even thinner than it really is.

We would like to comment here that the fur of the tiger isn't the only structure affected by evolutionary trickery. We would like to point out the human head. It seems relatively big and humans mates were tricked into thinking that there was really something in there.

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Professor at the UOL

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