Posted on 04/01/2014 2:24:42 PM PDT by bkopto
Zebras have evolved white and black stripes as camouflage to confuse lions. That's the conventional wisdom, anyway. But, as is so often the case, the conventional wisdom appears to be wrong.
New research in Nature Communications concludes that zebras' stripes are actually for preventing bites from nasty insects, such as tabanids (horse flies). For some reason, these flies avoid landing on black and white striped surfaces.
For their study, the authors collected stripe pattern data on seven wild equids: plains zebra, Grévy's zebra, mountain zebra, African wild ass, Przewalski's horse, kiang, and Asiatic wild ass. They then overlaid a map of these equids' ranges with information on predators' ranges, temperature, biomes, tsetse fly ranges, and tabanid ranges (which were determined by proxy using measurements on temperature and humidity). They found that the presence of equid stripes most closely correlated with the ranges of biting flies, such as tabanids and tsetse flies. In other words, equids are more likely to have stripes if they live in an area that also has biting flies.
Simultaneously, the authors' map mostly eliminated the other possible explanations that exist for zebra stripes: camouflage, predator confusion, body temperature control, and social identification. However, the presence of rump and leg stripes correlated with the range of hyenas, so it is possible that the stripes play a role in keeping hyenas at bay. The authors argue, though, that adult zebras are generally too big and powerful for hyenas to hunt, so it is unlikely that striping patterns play an important role here. Also, Asian equids that were once hunted by wolves and tigers do not have stripes.
Thus, the evidence from this and previous studies indicates that zebras have stripes to avoid flies, not lions.
(Excerpt) Read more at realclearscience.com ...
:: For some reason, these flies avoid landing on black and white striped surfaces. ::
That’s RAYCISS!
I really hate when science books say that an animal evolved something for it’s benefit. This is the classic lie that is told in grade and high school science classes. They make it seem that there was some intelligent mechanism that helped the animal to evolve, when instead if evolution is true then the only thing driving it is dumb luck.
Or, did the flies inherit a disdain for being whacked by the Zebra’s tail, and stop landing on black/white striped objects?
imagine the sort of intelligence tha Zebra would have needed....to have chosen....to evolve.
even we modern humans.....cough cough...lack that kind of brain and will power .
African wild ass and asiatic wild ass.... Definitely racist.
Lions don’t have stripes? Don’t tell the tigers.
I ate Zebra a few weeks ago in South Africa. Pretty tasty....for a striped horse/mule/ass/donkey.
Same thing with referees. You’ll never see flies around a referee. You do see a lot of bees around referees, though. Bees and kangaroos. You always see them around referees.
“I really hate when science books say that an animal evolved something for it’s benefit”
Of course the animal doesn’t plan the mutation. You are right. But, logically the mutations that are carried on either do nothing harmful or are beneficial to the animal and its descendents. Since things like the Zebra’s stripes are not found in the fossil record, we are reduced to DNA hints and rare skin or feather fossils which don’t give information about color (amber trapped insects do I think).
The article still doesn’t say if a Zebra is a white animal with black stripes or a black animal with white stripes
Don’t believe it. It was settled science. 97% of zoologists agree that zebra stripes serve as camouflage against lions. The camo-stripe deniers have some kind of an agenda. Once science is settled by consensus, deniers should stop trying to prove it wrong.
I can't answer the zebra question, but polar bears have black skin. Go figure...
“...zebras’ stripes are actually for preventing bites from nasty insects, such as tabanids (horse flies).”
If they bit zebras, they would be called zebra flies. How obvious can it be?
Valerie Jarrett should paint stripes on her sock puppet Obama. Zero needs some fly repellent.
It’s not evolution. It’s adaptation.
Damn Koch brothers!
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