The unique Zebra print is not one to miss. Easy to spot in a Saharan desert or a grassy African plain – zebras are one of the most striking looking animals to look at!
But have you ever wondered why? Is there perhaps, a secret to why this particular equid is so uniquely striped – perhaps, a zig to the zag!?
And while we love a good animal print, zebra stripes are a wildlife mystery. Puzzling biologists for decades. But now – thanks to new experiments involving horses dressed up in faux zebra print– it seems, we might just be on the precipice of resolving this age old zilemma!
If you want to know why zebras are striped, stick around till the very end.
Here’s what we know for now…
The Camouflage Theory
Don’t worry! You are not the only one thinking why zebras are born with this unique and contrasting pattern? A century ago, Darwin – the father of evolutionary science – pondered over the same.
Ever since, scientists have built on Darwin’s ideas– developing what we now call the camouflage theory. Mainly arguing that in a free-for-all jungle, where might is with the big & strong – sometimes, the easiest way to avoid being eaten, is to avoid being seen!
This view has been helpful in explaining why other animals in the wild are also striped or dotted. Such as cheetahs, tigers & giraffes! In the animal world, this could be an important (even life-saving) skill.
The bottom-line being that stripes can help zebras blend with their environment, and escape predators. Who are unable to distinguish the stripes from, say, grass blades or tree trunks. Predators could also find it hard to single out one zebra from this bigger (and rather) hypnotic-looking herd. Fortunately for the zebra, all this means a safe & timely escape!
But not everyone seems to agree. Critics have debunked the theory on multiple accounts. Reasoning that stripes are not perceived by predators (say, lions) who have much weaker eye-sights than one might think! In fact, one study found that zebras stripes are not even visible until predators are so close they can smell or hear the animal anyway!
Did You Know?
Just like human fingerprints, the stripes on a zebra are individual & unique. This means no two zebras can have the same pattern! Pretty amazing right?!
A Unique Marker of Identity
Are stripes just a way for zebras to socialize? Followers of the identity theory seem to think so. Arguing for the idea that stripes act as a kind of literal barcode! With Darwin himself suggesting that stripes may actually have a role to play in the process of zebra mating. This sits will with ample proof that courtship among animals is often based on the perception of physical characteristics such as size or color!
What’s Kipling got to do with it?
Did you know that in
Regulation of Body Temperature
Unlike reptiles, who are cold-blooded animals, mammals can control their internal body temperature – through a process called thermoregulation.
If that’s true, could zebra stripes be nature’s way of keeping it cool? After all, the scaling Savannah Sun is no easy place to survive for day-loving animals like zebras. And remember, zebras also tend to graze in the grasslands for hours – which means their bodies have a greater need to shield against the Sun.
Not just that – compared to other grazing animals such as horses – zebras tend to digest food more slowly, which means having to graze in the scorching heat for longer.
Thanks to the work of physicists, we know that different types of pigments tend to absorb heat at different rates. This means that white stripes are better at reflecting the Sun’s light. And thus retaining less heat compared to the neighboring patches of black.
In fact, according to one study, it was found that during the warmer hours, black stripes were 12-15 Celsius degrees higher than white stripes – an observation found to be consistently true in later studies!
Scientists who think of stripes as a wearable air-conditioner have studied the movement of air above a zebra’s skin. Finding a good deal of evidence for how air tends to travel more quickly over black stripes than the white ones. Creating a swirling motion right above the areas where the stripes meet. With this fan-like motion eventually producing a cooling effect on the body – especially around the animal’s back.
The Fly-Repellent Effect
Today, experts seem to have found a better, more tenable answer. New experiments have shown that traditional views on the subject could have been wrong all along. Could the zebra print actually have nothing to do with bamboozling those big scary felines? But a way to shield the animal against tiny little flies. Bet you didn’t see that coming?
Perhaps, the best evidence in favor of the bug-repellent hypothesis comes from a recent study where horses masqueraded as zebras. With the behavior of flies around both (zebras and horses) studied using HD cameras. A frame-by-frame analysis showed that in cases of horses (either all-black or brown), flies were more likely to make a controlled landing.
Another study found that in hotter parts of the Africa, zebras tend to have more stripes – correlating this with a greater population of flies. This view finds that zebras – in particular, are more vulnerable to blood-sucking flies as their coats tend to be thinner. Giving flies more easy access to the skin below.
But to be fair, any combination of these factors may have made it possible (or even necessary) for some equids to develop an innovative way to repel flies. To discover more about the comparative resistance of horses and zebras to flies, click here.
Why Are Flies Harmful for Equids?
Slurping on the blood of Savannah animals, flies are no ally to the horse-kind. In the hot temperatures of Africa, flies tend to be everywhere. Tsetse, tabanid and horse flies are particularly common across the entire continent.
At their worst, these blood-sucking parasites can transmit a number of diseases which may be potentially fatal – such as:
- Equine influenza
- African horse sickness
- Infectious horse anemia
- Sleeping sickness
But here’s why striped equids like zebras may have less reason to worry?
An Optical Illusion
Zebra stripes have been found to create an optical illusion that confuses flies – up until the very last second! Making it difficult for flies to make a controlled landing as they are not sure when they are about to hit a solid body. Travelling past the zebra or colliding and bouncing off the animal’s skin. So, all in all, this means that the high contrast between black and white tricks a fly’s low-resolution vision – a vision that mostly relies on their ability to sense movement.
In A Nutshell
As scientists mull over the real purpose behind zebra stripes, it seems we may be getting closer to the truth. But before that, we need to conduct more tests with coats of different patterns, contrasts and thickness.
For now, answers to this genetic mystery have tended to fall under four broad banners. So stripes could be:
- A camouflage against predators.
- A fly or bug-repellent effect.
- A cooling mechanism.
- An identity marker.
We hope you had fun learning about the purpose behind zebra stripes! To discover more about mysteries of the natural world, follow our space at FluffyPlanet for regular updates!