By Leigh Kemp
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.Debate has raged over time as to why animals have particular colours and patterns, with many theories been put forward. In fact there are so many theories that confusion mostly reigns in relation to this subject.
In animals with uniform coat patterning the individuals may be defined by something as small as whisker spots, such as the case with Lions.
Coat patterning may differ subtly from individual to individual but in the case of some animals such as Giraffe the coat patterning across Africa have necessitated them to be sub-classified, such is the dramatic variation in patterning. There are eight known sub-species of Giraffe in Africa - with some very dramatic patterning variations such as the Reticulated Giraffe of East Africa.
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.
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.
In the southern giraffe it is 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.
One of the more debated aspects of animal patterning concerns zebras and the question is asked why they have stripes. There are many theories around this, such as to confuse predators when they are running in a herd, but the high incidence of zebra predation across the continent puts paid to this theory. The theory of camouflage is also lacking in validity when viewing a herd on the plains as they stand out more than most other species.
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.
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?
The debates around colouration and patterning will continue forever, but what is certain is that the dramatic wildlife of Africa, in all patterns and colours, will continue to enthral for generations to come.