ARE ZEBRAS BLACK WITH WHITE STRIPES OR WHITE WITH BLACK STRIPES?



It is hard to argue that Zebras are without doubt one of the most exotic and stunning of all the horse species, but there is one question that haunts many an idle mind:
'...are Zebras white with black stripes or black with white stripes?...'
Well, go back a few years and it was commonly believed that zebras were white animals with black stripes. Why, because some zebras have white underbellies. However this thinking has now changed with recent embryological evidence. Now it is believed that the animal's background color is black and the white stripes and bellies are additions. What difference this makes to an individual Zebras is surely negligible but why would an animal whose natural habitat would be out on the open plains have such a bold and striking pattern? Surely this would put the Zebra at an increased risk of being predated by Lions?

Why do Zebras have stripes?

There have been a number of reasons put forward as to why zebras are striped.

1. The vertical striping may help the zebra hide in grass and brushland. While seeming absurd at first glance, as grass and brushland are neither white nor black, it is supposed to be effective against the zebra's main predator - the lion.

If you consider that lions do most of their hunting at night when their night vision - although excellent - functions in black and white, a herd of black and white zebra begins to make sense.

2. Another belief is that since zebras are herd animals, their stripes may help to confuse a predators. A number of zebras standing or moving close together may appear as one large animal, making it more difficult for the lion to pick out an individual zebra to attack.

3. It has been suggested that the stripes serve as visual cues and identification. Although each striping pattern is unique to each individual - the variation greatest is found in the shoulder region -  it is not known whether zebras can recognise one another by their stripes. And lets be honest here, it is quite unlikely!

Image credit - http://www.msafirimag.com/
4. One innovative experiment suggested that the disruptive colouration is an effective means of confusing the visual system of the blood-sucking tsetse fly. However, the Burchell's zebra - unfortunately now extinct - was immune to the bite of the tsetse fly, so perhaps more work in this area is needed.

5. There are other, alternative theories for the stripes which suggest that the stripes coincide with fat patterning beneath the skin, or that they serve as a thermo-regulatory mechanism for the zebra, or that wounds sustained disrupt the striping pattern to clearly indicate the fitness of the animal to potential mates.

Whatever the truth behind their stripes may turn out to be, using stripes as a defence against predators has only helped them so far. Why? Because the largest threat to Zebra populations is the risk of being hunted for their skins, and meat by man.

For related articles click onto the following links:
ARE ZEBRAS BLACK WITH WHITE STRIPES OR WHITE WITH BLACK STRIPES?
CAN ZEBRAS BREED WITH HORSES?
ZEBRA

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