Great Safari Animals

‘How the zebra got its stripes’ sounds like a tall tale from Rudyard Kipling’s Just-So book of stories. In fact it could have been the title of a new piece of research which claims to have found the answer to the mystery of why zebra sport such beautifully distinct black-and-white coats. There are three species of Zebra native to Africa: plains, mountain and Grevy’s. Travellers keen to see all three species would be certainly clocking up the miles while on safari in Africa.

Zebra

Those embarking on a Zambia safari are most likely to catch a view of the Burchell’s zebra, a subspecies of the plains zebra commonly found in Luangwa Valley. South Africa offer good opportunities to see the mountain zebra, while the Grevy’s is native to both Kenya and Ethiopia.  While each species has evolved to suit their native environment, the iconic black and white stripes remain consistent.

Theories put forward to explain the zebra’s stripes include the idea that a mass of stripes can confuse predators. Then there is the school of thought which points out that the striped patterns are as unique as human fingerprints and help zebra recognise other individuals.  These were all theories which were familiar to the Hungarian and Swedish university students who set up five life-like model horses in a grassy field in rural Hungary. One model horse was painted with spots, one was painted brown, one was painted black, one was plain white and the final one was painted with black and white vertical stripes.

All of the dummy horses were daubed with sticky insect glue and it was found that the horse with the zebra stripes attracted the fewest amount of flies. Further research suggested that the stripes reflected sunlight in an unpredictable way; making it harder for blood-sucking flies which inhabit zebra environments to identify zebra.

Now the researchers, who acknowledge that other stripe theories have yet to be disproved, must gather evidence to determine whether blood-sucking flies influence the zebra’s natural selection process sufficiently to affect their evolutional development.

Why The Leopard Has Spots

 The zebra scientists’ report was published in the Journal of Experimental Biology on 9th February 2012 and covers similar ground to research published in 2010 which examined the colours and markings of 35 species of wild cats. The wild cat research was led by Will Allen of Bristol’s School of Experimental Psychology.  Allen claims to have determined that the size and complexity of patterns on animals such as leopard, tiger and cheetah seems unrelated to body size, prey size and sociability. The research does suggest that:

  • The more time cats spend in trees, the more likely they are to be patterned; especially with irregular and complex patterns
  • Cats using closed environments (such as forests, rather than, say, big open grasslands) are more likely to have complex patterns
  • Dense forest habitats typically have more variable textures and colours of environment so that patterns can be more random
  • Nocturnal hunters are more likely to develop complex patterns

The researchers stressed that patterns can emerge or disappear very rapidly as species evolve. Recent habitat or pattern-shifts can account for mismatches – possible examples being Borneo’s bay cat; whose plain coat shouldn’t, on paper, suit the closed environment it operates in. Which brings us back, in a roundabout way, to the zebra. Allen’s study found no support for the proposition that vertical stripes are associated with the zebra’s grassland environment; only the tiger can accurately be classified as having long vertical stripes and it is not a typical grasslands creature! Tigers have the perfect camofluage for their environment so the researchers were puzzled why vertical stripes are not more common in cats and other mammals sharing the tiger’s territory.

James Christie writes for Safari Consultants, who offer a wide range of adventures holidays including Zambia, South Africa and Masai Mara Safaris.