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A D MACKAY © All Rights Reserved

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It is recognised now that we are, as humans, genetically closer to chimpanzees than gorillas and so it follows from this that the pioneering savannah ape must have been a chimpanzee rather than a gorilla. However, the process of reversion (described elsewhere) can confuse direct genome comparisons. In actual fact, the gorilla could have been the original savannah pioneer. This is because gorillas are likely to be derived  from chimpanzees anyway (having evolved for mountain dwelling - where it is much cooler and where the forests are less dense). Many of the derived characteristics of gorilla genetics, however, could have been abandoned in a process of reversion - with the result that many gene sequences could return to a pattern more in common with chimpanzees. This could have occurred at a much later stage of the savannah ape’s evolution, when they were defending themselves with crude weapons - and great size and brute strength were no longer necessary attributes - a more gracile form being sufficient.

 

Food Resources

 

New pioneers to savannah/scrub-land would perhaps have the following food resources. I have selected these - bearing in mind the eating habits of gorilla and chimpanzees and their capabilities of procurement. These animals are considered to be omnivorous but their diet majors on leaves, flowers, fruit and seed. They do eat a variety of insects and occasionally kill monkeys (mainly colobus) and infrequently kill and eat their own kind.

 

Leaves and seed pods of Acacia species and the gums they exude from their bark would probably provide the staple of pioneering apes. Insects such as termites are widely available and as many a five million insects can be found in one termite mound. Mounds can be easily broken away by hand, stone or stick and it is possible that this method of nest damage was within their capabilities of these apes. Constant digging into termite mounds with crude implements would increase motor skills and technical know-how in ‘tool’ choice. Improved techniques would be copied by younger generations and other groups.

 

Locusts are often present in vast numbers and could provide some nutrition. There are many other types of insects too, including beetles, crickets and bugs.

 

Turn over any stone in this part of Africa and you will find a host of other creatures too - including scorpions, worms, and spiders. There are also some reptiles which are easy to catch including lizards, chameleons, tortoises, and small crocodiles - which live near lakes and rivers. Bird’s eggs like those from the many large species which nest near the African lakes would also provide the occasional treat.

 

Coloration and Skin Covering

 

If we consider these pioneering species of the savannah lands were like mountain gorillas - one of the biggest problems in a new environs would be associated with the thickness of their coat - ideal for cool nights on the mountain slopes - but inappropriate for the harsh sun-soaked savannah. The black coloration not only absorbs heat radiation but also makes them conspicuous in the new landscape.

 

There would be natural selection for a sparser hair covering throughout the body - except for the head region where it would serve as protection against ultraviolet light damaging the brain. Thick hair on the head would act like a tropical pith helmet protecting both the brain and brain stem. Those individuals with thin hair on their heads would no doubt suffer the deleterious effects of sunstroke.

 

I believe this is how we arrived at our own head hair characteristics with regards to density and growth pattern. It is likely the hair would have been without any crinkle as I believe the African type crinkling is a modern derivation - for reasons I will discuss in another section.

 

There would be natural selection for cryptic coloration - that is a coloration which blend more effectively with the savannah land back-drop. Those that were paler or more cryptic would be more successful in concealing themselves from predators. In many parts of East Africa, river beds and erosion gullies, termite mounds and ‘pathways’ are often of a red earth colour. The river beds are areas where early savannah apes would have needed to collect water and would have been most vulnerable to predator attack. Other areas of East Africa, commonly, have the grey soil type known as ‘black cotton’. So coloration could have been either reddish brown or grey in relation to the two soil types. Another possibility could have been cryptic coloration in relation to the savannah vegetation itself and this could have been the flecked gold and grey of the schemes adopted by vervet monkeys, baboons and mandrills.

 

The single tone grey was perhaps the most likely colour scheme to be adopted by early savannah apes as it is the one commonly used by  several other creatures which frequent the same areas. These are the wart hogs, elephants, rhinoceroses and hippopotamuses. Perhaps it is no coincidence that all these animals, too, have sparse hair coverings on their bodies.

 

 

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