If there ever was a species that rocked the scientific world, it was Homofloresiensis. It was so tiny, so small brained, so out of time and place. Found on the Island of Flores in Indonesia in 2003. How did it get there? It had to be by boat of some kind. How does it fit in our family tree? That is something no one has been able to figure out yet. It was the WTF reaction by researchers as well as its diminutive size that complicated its acceptance into the species Homo. The keyboarding went quantum. It was a pathological anomaly. It had this disease or that syndrome. You name the disorder, floresiensis had it. The most common choice was Down's Syndrome, which is very rare among primates. Only two known cases have ever been found. When more bones and tools were found, we were asked to imagine a tribe of Down's Syndrome dwarfed hominins sailing off to Flores and establishing themselves as hunters. Really.
Our brains are truly the one thing that has separated us from everything else that has lived on this planet, and it was happenstance. It evolved serendipitously, as a side effect of our environmental lifestyle, and the tale is a glorious tribute to the beauty of evolution. Let me be clear. We did not need a big brain to survive. Nothing else has one, and all life here progresses fine without one. Its usefulness allowed us to conquer every environment. So what did we do that was so right?
The southern Iberian Peninsula near Gibralter was the last outpost of Neanderthal. They languished there until as late as 24kbp (thousand years before present). This area offered several survival elements They had warmth, seafood, and cliffs. With so much game gone at this point, they probably relied on food provided by the sea and cliffs. The cliffs also offered security from intruders. Climate had undergone drastic changes. A volcanic eruption 40kbp began a series of extremely cold seasons. This caused a loss of game animals and the calving of icebergs that also lowered temperatures. This is seen as the match that broke the camel's back for our cousins. Some researchers believe that Neanderthals couldn't make warm enough clothing, but that seems ridiculous. These were a people long used to living in colder temperatures. After all, aren't they built for the cold with their shortened arms, legs, and stocky bodies, just like Arctic people today?
Perhaps the greatest frustration in evolutionary biology is bipedalism. Why walk on two legs if running on all fours is faster? Well, for the last hundred years or so, we were taught we stood up to see over the tall grass of the savannah, much like meerkats. This freed our hands to carry food, make tools, and become the mighty hunter. That theory went out the window when the entire Savannah Hypothesis bit the dust. Ardipithecus and Australopithecines are now viewed as semi-woodland dwellers. Here we developed two-leggedness because we stood on branches, using the hands to steady us, employing a light touch. They have even determined how strong the touch would be as we steadied ourselves, swaying branches and what the force of a breeze would be. Some people have got too much time on their hands!
Today's view of human evolution is rapidly shifting from the now-defunct Savannah Hypothesis to the more believable coastal living scenario. No longer is the idea that we developed our brains while hunting on the savannah held true. Some have opted for a semi-woodland environment, but this, too, is leading us to coastal living as the preeminent ecosystem where we evolved from a small-brained biped into a large-brained one. Picture, if you will, a group of LCAs (Last Common Ancestor) living on the east coast of Africa, blocked to the west by the Ethiopian Escarpment, and to the east by the Red Sea. There is plenty of freshwater. We know this because there is a continuum of freshwater springs in this area today, produced by the movement in the East African Rift System. Seafood was plentiful. Even the old and the very young had all they could eat. There was volcanism and rift movement and occasionally openings in the rift would come about and some would leave this paradise for the interior. They may have gotten lost out in this different world and been unable to make their way back. Or, the pathway they took out of their normal environment may have been closed off by rift activity. Unless you think bipedal forms of hominids sprung up spontaneously all over Africa, this is the only interpretation. The likelihood of that is remote when you consider the extremely different environments in which this adaptation would have had to occur.
We are called the naked ape because we show more skin than any other primate. The gentleman in the picture appears hairless, but we know his hair has been removed for the shot. However, it may surprise you to know that we have just as many hair follicles as a chimpanzee. Our hair is just finer and much shorter. So why do we show so much more skin than any other primate?