Studies in nature

All individuals within a mammal species have distinctive characteristics, making them distinguishable from each other (just like fingerprints in humans). In many species these individual characteristics are not immediately obvious. In lions for example, where the colour is uniform, researches identify individuals by the whisker spots.

The differences in individual leopard and cheetah may not be immediately obvious due to the plethora of spots. However, upon closer inspection of the skin patterning, unique individual markings may be identified.

Unique individual patterns on the skin are more obvious in species such as zebra, wild dog and giraffe where the patterning is more pronounced.

High achievers

In giraffe this phenomenon goes a step further. Not only are the patterns different for each animal but in Africa there are eight sub-species of giraffe and they in turn have a variation in the sub-species patterning. The skin patterning of some of these subspecies is unique to that subspecies (e.g. the reticulated giraffe from East Africa).

Upon close inspection, however, traces of the recent common ancestry of giraffe can be noted in the patterning of the various subspecies. The southern giraffe shows up these traces more so than any of the others. What the original patterning of giraffe was, is debatable.

Southern giraffe

The more common southern giraffe, occurring in most of southern Africa, shows the widest range of patterning adding to the debate that it may be the original species and the other subspecies derived from the southern Africa species.

It is believed that male giraffe are darker and that the colour darkens with age. Although this is often the case it's not an entirely correct theory, as there is evidence of very dark females . In the southern giraffe it's not only the shades but the shapes of the patterns that differ. In any one group of giraffe a number of shapes can be observed, including round, smooth edged, and jagged edged.

It's not all black and white

Zebra stripes have been the topic of many theories and discussions. There are three types of zebra in Africa: the Grevy’s zebra of East Africa, the mountain zebra of southern Africa and the plains zebra (also known as the Burchell’s zebra) that is widespread across Africa.

There is a distinct difference between these three types. The Grevy’s is the most distinctive with its thinner more pronounced markings. The stripes of the mountain zebra lacks a 'shadow' stripe, and this zebra's stripes don't wrap around to the stomach. The plains zebra is the only one where the stripes stretch all the way onto the stomach. The southern variety of the plains zebra has a shadow brown stripe in the white stripe, the reason for which is unknown.

Why the stripes?

The question of why zebras have stripes has many theories attached to it. Camouflage can be ruled out as the black and white stripes do not suit the zebra’s habitat preference of the open plains. The theory that the stripes manage to confuse predators when zebra are running in a group needs to be researched properly, because the fact remains: zebra are still the favoured prey for lions and hyenas in many parts of Africa.

An alternative theory

Can the stripes not have been a survival adaptation in the past where a combination of terrain, vegetation and predators played a part in the evolution of zebra stripes? Because of less recent danger to the species the patterning has not had to evolve further?

A guide's perspective

Present in a lion's eyes, are both rods and cones (these are light-receptive cells in the eye)...but like all cats, the lion's eyes contain, primarily rods. This in effect indicates that lions have a little ability to see in colour but have a great ability in seeing in low light. For a lion to see primarily in colour, the eye would have to contain primarily cones. Having determined this, we now have to look at how the zebra stripes would aid the animal in escaping detection and/or attack. In my opinion, zebra stripes are not so much camouflage, as they are shape breakers, enabling the zebra to be relatively undetected by predators, as long as the animal remains still. I have seen this work at very close range, where a lion walked past a young zebra, a mere 15 metres away.

Once the attack takes place though, I have noticed that zebras flee as a unit, often running shoulder to shoulder...until either one is caught or turns the wrong way and gets separated, or the group successfully evades the attack. In my opinion (and I stress this to guests whilst discussing this phenomena...that it is my opinion), is that the zebras, by running as a unit, have better chance of confusing the lion's depth of field (very much like your camera does when there is a blade of grass between the leopard and a possible award winning photo...hehe), for those few critical seconds that it would take for the zebras to get away.

Lions do not chase their prey indefinitely, so every second in a chase, becomes all important. To my knowledge, this theory has not been proven yet, but as a guide who has witnessed several lion/zebra interactions, I find it plausible. I do not however believe that the zebra stripes are individualistic because, it is the way that a foal recognises its mother (see the documentary: Patterns in the Grass), as I believe that recognition is vocal. I have witnessed a mother zebra call its foal from a location that the foal could not see the mother, and the foal responded immediately. As for zebras being the preferred prey of lions? Well I think that statement is actually an area specific one (the most prolific species in that area). The majority of lion kills recorded are on impala, waterbuck, wildebeest and giraffe. In the Masai Mara and the Serengeti, I would imagine that lions would prey predominantly on zebra and wildebeest, because of the sheer numbers of those species.