It’s true, in a round about way! Thousands of years ago when us Homo sapians were still evolving and deciding weather or not standing on two feet was a good idea or not something else was going on too. Our bodies were becoming hairless. Like most mammals, our predecessors’ bodies were covered in hair, much like the great apes we see today. It was this hair that protected ‘us’ from the biting flies, mozzies for example. After we lost the hair from most of our body we were more susceptable to biting insects. Therefore, our bodies became a feeding station for more and more species of biting insects. Consequently more and more parasites evolved to depend on Homo sapians for food and development during their life cycle. For the most part the parasitic diseases we hear about today would not be round if we humans weren’t around. (N.B. The majority of human parasites have evolved from animal parasites, if humans weren’t around these strains would most likely prevail).
Well that is all very well, but an obvious question has to be asked, why on earth would ‘we’ evolve to be ‘almost’ hairless if it was potentially detrimental to our evolutionary ‘fitness’? (N.B. That last sentance just beat the world record for the most inapropriate use of inverted commas 🙂 ) Think of the where human ancestorial line originated and the climate, you should be thinking about Africa and hot…mid-day sun – very hot. Now think about what most of the animals are doing during the mid-day sun, especially the predators. I’m having flash backs of the BBCs’ Big Cat Week – Live where Simon King would say “now lets move to the lions…(dramatic pause)…oh and there is movement, no no that our producer with a big poking stick!”. What I’m trying to say is they do very little.
So why…?
Answers in the comments section, one person I’m sure will know this is Alan Gunn (Lecturer at JMU), can you out smart the Gunn ;-)?
The Zoological Blog 