If Zebras' Stripes Aren't For Camouflage, What Are They For?

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If Zebras' Stripes Aren't For Camouflage, What Are They For?

A new study has revealed that zebra stripes actually provide no benefit in terms of camouflage - so what are they for?

It has been the prevailing wisdom for centuries, if not longer, that the zebra's distinctive black-and-white striped coat is there for camouflage. The theory goes that the zebra's primary predators, such as big cats, can't discern the animal's pattern from nearby tall grasses. To a human eye, of course, zebras stand out against the golden-brown of the savannah like a sore thumb, but we figured "it's a lion thing," and let it go.

Now, new research suggests that even big cats aren't affected by the stripes.

"The most long-standing hypothesis for zebra striping is crypsis, or camouflaging, but until now the question has always been framed through human eyes," says the study's lead author, Amanda Melin, an assistant professor of biological anthropology at the University of Calgary, Canada. "We, instead, carried out a series of calculations through which we were able to estimate the distances at which lions and spotted hyenas, as well as zebras, can see zebra stripes under daylight, twilight, or during a moonless night."

Basically, we've never actually looked at a zebra through the eyes of a lion. As it turns out, lions and hyenas can clearly separate a zebra from its surroundings, even under low light conditions. What's more, each of those animals' enhanced senses of smell and hearing would more than compensate for a lack of visual acuity.

To make matters more confusing, even zebras don't seem to care much for the stripes of their friends. They may be able to tell apart individuals, but all social animals can do that without such garish signals.

It might be of note that none of the research rules out "razzle dazzle" camouflage, wherein the subject isn't hidden from view, but their movements are obfuscated. In World War 1, for example, warships were painted with strange, confusing designs, that made them seem as if they were moving in different directions than they actually were, frustrating torpedo operators.

Possibly, zebras' stripes fulfil the same function - when they run, a predator's eyes have a hard time tracking them. No one can say for sure just yet.

What do you, scientists of The Escapist, think the stripes might be for? Is there an angle no one has looked at yet?

Source: PLOS One, Science Recorder, Euraklert

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Wasn't that known until now? I swear I've read an article on Cracked that mentioned it. Given that last I was reading Cracked regularly was 3-4 years ago, that article must have been at least 3-4 years old.

Razzle-Dazzle makes sense to me. Stationary camouflage though? Never made the slightest lick of sense!
If cats had shitty eyes they'd not have such big, well developed ones and instead would primarily use their other senses for hunting.

Still; ruling something out is ALWAYS good science!
Eventually you are left with the experiment that gives you the answer through exclusion! :D

I watched it in a documentary somewhere but a Zebra's stripes ARE camoflauge. But in a very unconventional way. Their most common predators such as lions can't really see in color at all. Just in black and white. As such the stripes and how they are formatted are meant to be really confusing and disorienting to them. Where as other animals like us- that can see in all colors of the rainbow (for the most part.) see a Zebra and they stick out like a sore thumb.

Who says they're for anything? They might have been part of the parcel in some other mutation.

It's a common misunderstanding about evolution that it's a process that moves towards purpose and effectiveness, while it's just a weighted random number generator. Plenty of things, even in our own bodies (the appendix, male nipples, wisdom teeth, the tailbone), that have no purpose whatsoever, but that just happened to have survived. Granted, the zebra stripes might seem like a particularly extravagant example, but that doesn't mean they must have a purpose.

Sex.
Evolution has two uses.
One is survival, the other is reproduction, which leads to the survival of the race.
If it's not the help them survive, it's to help them reproduce.
The strips are a mental aphrodisiac for them.

There, mistery solved. moving on to Gold fish. Are they golden to get humans to buy and feed them? Did science go too far?

PatrickJS:
It might be of note that none of the research rules out "razzle dazzle" camouflage, wherein the subject isn't hidden from view, but their movements are obfuscated. In World War 1, for example, warships were painted with strange, confusing designs, that made them seem as if they were moving in different directions than they actually were, frustrating torpedo operators.

Even before I got to this paragraph that was exactly my reaction to the OP claim that standard camouflage is the "prevailing wisdom". ie, "Huh, it is? I thought the current theory was about disguising movement and camoflauging individuals within the herd so predators cant pick out and target specific zebras".

Wait... is it not so we can scan them and find out how much they cost?

I always understood that the prevailing theory wasn't that it prevented the predators from seeing them, but that it prevented the predators easily picking out a single zebra in the group.

Of course, mot biologists will tell you that often times all they can give is a shrug and a best guess for this sort of thing. Evolution is really strange.

Hmm? Last I heard it was to help with temperature regulation primarily.

Wasn't this already claimed years ago.
I mean they already came up with an alternate hypothesis.
It was Heat Management.
Basically the alternating white and black stripes caused un-even heating, this causes a draft to form lowering temperature.
The study found no relationship between the pattern of zebra stripes and the presence of predators, but found that the hotter the temperature, the more stripes a zebra had.

I always thought it was a social adaptation that made it harder for predators to pick out individual zebras from the herd, making it less likely that an individual zebra would be picked out over any other.

The intention not to preserve zebrakind as a whole, but to preserve the individual zebra.

<_< or who knows, maybe the predators artificially selected the zebras to look that way so that it was easier to find them when they got hungry.

ThatOtherGirl:
I always understood that the prevailing theory wasn't that it prevented the predators from seeing them, but that it prevented the predators easily picking out a single zebra in the group.

Of course, mot biologists will tell you that often times all they can give is a shrug and a best guess for this sort of thing. Evolution is really strange.

That's what I was thinking, too. That the striped patterns makes it difficult for a predator to pick out a single zebra from the herd. Not that it made it difficult for them to pick out a zebra from grass.

I thought it was clear that the stripes were for MAXIMUM SASS image

The razzle dazzle and heat regulation ideas make sense though.

A baby cheetah looks like a honey badger. Maybe the Zebras are trying to emulate a vicious beast which took a dead end turn on the road of evolution

http://worldsafaris.com/blog/do-baby-cheetahs-mimic-honey-badgers/

Zacharious-khan:
Wait... is it not so we can scan them and find out how much they cost?

lmao......i dont know why but i found that hillarious and i rarely laugh at other peoples jokes on here.

The real question here is "Is it pronounced, ZEE-brah? Or ZED-brah?"

We need our top men on this.

I think its to help out predators the stripes highlight the best places to cut and therefore maximise the number of top quality steaks that can be carved out of each zebra
Lions do not have well developed manipulators on their paws so holding a knife is likely difficult and every bit of help they can get is a bonus

TheSYLOH:
Wasn't this already claimed years ago.
I mean they already came up with an alternate hypothesis.
It was Heat Management.
Basically the alternating white and black stripes caused un-even heating, this causes a draft to form lowering temperature.
The study found no relationship between the pattern of zebra stripes and the presence of predators, but found that the hotter the temperature, the more stripes a zebra had.

This is what I came here to write. As far as I understand, this is the most widespread hypothesis in zoologist circles today.

BeerTent:
The real question here is "Is it pronounced, ZEE-brah? Or ZED-brah?"

We need our top men on this.

Neither, it is ZEH-bra.

There's a lot of sound reasonings here. the only thing I can really add is that

Stripes make you go faster.

I always thought it was so it was hard to pick one 'cos it's hard to tell where one ends and another begins.

Black and white stripes on a brown back drop is just stupid, which is why lions, tigers, hyenas are all kind of the same colour (ok tigers are more orange and have stripes but it's not like they are flymango pink).

It's like wearing snow camo in spec ops the line.

I don't want to seem like some know it all smart arse ('cos quite frankly I'm an idiot! especially when you guys start talking math!) but even as a kid I knew that zebras didn't have stripes to be camo in their environment but more like camo with each other.

The next question on the list of many, in this thread, is:
Is the Zebra white with black stripes, or black with white stripes?

King_Julian:

Zacharious-khan:
Wait... is it not so we can scan them and find out how much they cost?

lmao......i dont know why but i found that hillarious and i rarely laugh at other peoples jokes on here.

I hadn't even thought about that before xD

Dragonbums:
I watched it in a documentary somewhere but a Zebra's stripes ARE camoflauge. But in a very unconventional way. Their most common predators such as lions can't really see in color at all. Just in black and white. As such the stripes and how they are formatted are meant to be really confusing and disorienting to them. Where as other animals like us- that can see in all colors of the rainbow (for the most part.) see a Zebra and they stick out like a sore thumb.

Can Hyena's see in colour? Cuz they don't seem to have problems murder zebras for food.

Wow was this article really needed? Well gee Idk aren't the stripes apart of them? It's not like they hand crafted the stripes to ward off against lions or for any other purpose.

BiH-Kira:
Sex.
Evolution has two uses.
One is survival, the other is reproduction, which leads to the survival of the race.
If it's not the help them survive, it's to help them reproduce.
The strips are a mental aphrodisiac for them.

There, mistery solved. moving on to Gold fish. Are they golden to get humans to buy and feed them? Did science go too far?

This right here. There is a pretty good rule of thumb among evolutionary biologists: If a trait has no recognizable adaptive function derived through natural selection, it is very likely that it has been derived through sexual selection.

Does it have to serve a purpose?

Evolution doesn't mean any and all traits a living organism has are somehow beneficial and selected for. Evolution means any and all traits a living organism has are traits that, usually, don't kill it before it manages to reproduce. That's it really. They don't have to be beneficial, they can be harmful. As long as they're not harmful enough.

As the saying goes. It's not the bear you have to outrun, it's your fellow men. Evolution isn't selecting for ultimate organisms, it's just selecting for not horrible enough to get oneself killed before reproduction.

Hagi:
Does it have to serve a purpose?

Evolution doesn't mean any and all traits a living organism has are somehow beneficial and selected for. Evolution means any and all traits a living organism has are traits that, usually, don't kill it before it manages to reproduce. That's it really. They don't have to be beneficial, they can be harmful. As long as they're not harmful enough.

As the saying goes. It's not the bear you have to outrun, it's your fellow men. Evolution isn't selecting for ultimate organisms, it's just selecting for not horrible enough to get oneself killed before reproduction.

I'll second this. There are a lot of inherited traits which serve no real function. They just persist because they didn't have too negative an effect on a species' ability to survive and procreate.

The sex hypothesis is quite good, but doesn't explain why both males AND females exhibit the same pattern.
In other species, only males ou females wear a different wardrobe, to standout from their challengers.

IMO, it's probably a movement thing: while running and dodging, stripes make it harder for lions to estimate the real distance between their claws and their target (see the first volumes of Ruroni Kenshin). Yet, lions adapted themselves recently, and are now able to shrug it off, leaving zebras with a useless visual artifice.

Maybe in 10 000 years, we'll see full-gray zebras... or plasma-farting zebras.

Nononono...It's sole purpose is to be a metaphor (or simile, whatever) for all our racial harmony songs.

Wait, no one remembers the actual study establishing biting flies as a quantifiable reason for the stripes?

EDIT: http://motherboard.vice.com/read/the-reason-zebras-have-stripes-isnt-what-you-think

Apparently they are a deterrent for tsetse flies and a few other fly species. In fact, the only equine species with stripes live in areas with very high concentrations of those flies. As the concentration of these flies increase in the region, the concentration of striped equine species (Zebras and their like) are found there too whereas non-striped species goes down. Studies have shown that these flies land on striped surfaces far less than non-stripped surfaces. That's interesting.

So there is a direct correlation between those flies and zebras. The only question remaining is why other species don't present more heavily in those regions too since they are also vulnerable to flies. But this particular mutation could be rare or the ancestor of this species may have been more vulnerable to the flies than other kinds of animals.

It's also possible that these stripes serve additional purposes, but it is clear this is at least one advantage it is for.

PatrickJS:
In World War 1, for example, warships were painted with strange, confusing designs, that made them seem as if they were moving in different directions than they actually were, frustrating torpedo operators.

To put it a little more accurately - In WW1 warships were painted with strange, confusing designs, that were intended to make them seem as if they were moving in different directions than they actually were. There's very little evidence to suggest it actually worked. It's also worth bearing in mind that there's not even much agreement on whether that was actually the intention at all - various people both at the time and later have made conflicting claims about whether it was supposed to obscure the heading (so that a submarine would end up in the wrong position when trying to set up an attack), make range-finding difficult for actually targeting weapons, or simply to make identification trickier.

The White Hunter:

Dragonbums:
I watched it in a documentary somewhere but a Zebra's stripes ARE camoflauge. But in a very unconventional way. Their most common predators such as lions can't really see in color at all. Just in black and white. As such the stripes and how they are formatted are meant to be really confusing and disorienting to them. Where as other animals like us- that can see in all colors of the rainbow (for the most part.) see a Zebra and they stick out like a sore thumb.

Can Hyena's see in colour? Cuz they don't seem to have problems murder zebras for food.

Hyena's also have the benefit of having some monstrously strong jaws to boot. I'm not saying it's 100% failsafe (since Lions have successfully hunted and killed Zebras.)

But comparing our feline friends to hyenas are a bit unfair. The little laughers are somewhere around 70% successful in all their hunts while Lions are a poor 30%. So failure to catch zebras are the least of their worries.

Dragonbums:

The White Hunter:

Dragonbums:
I watched it in a documentary somewhere but a Zebra's stripes ARE camoflauge. But in a very unconventional way. Their most common predators such as lions can't really see in color at all. Just in black and white. As such the stripes and how they are formatted are meant to be really confusing and disorienting to them. Where as other animals like us- that can see in all colors of the rainbow (for the most part.) see a Zebra and they stick out like a sore thumb.

Can Hyena's see in colour? Cuz they don't seem to have problems murder zebras for food.

Hyena's also have the benefit of having some monstrously strong jaws to boot. I'm not saying it's 100% failsafe (since Lions have successfully hunted and killed Zebras.)

But comparing our feline friends to hyenas are a bit unfair. The little laughers are somewhere around 70% successful in all their hunts while Lions are a poor 30%. So failure to catch zebras are the least of their worries.

Hyenas kill the most shit on the African continent, they're by far the most successful chase predator, Lions tend to scavenge their kills a lot. They have also been recorded having actually killed a Hippo, which is fucking scary tbh.

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