By Steve Chadwick
Courtesy of Peter Hyslop
We have been hiking for a very long time. Our lineage split off from the apes around 10 million years ago. A further departure was made from the chimps some 7 million years ago. Though they remain to this day our closest living species relative as we retain 99.2% chimp DNA. We were not walking yet – not in the bipedal sense anyway.
We moved on, so to speak, passing through various Australopithecus stages which it seems were mostly arboreal in habitat; still not walking. We were Ramapithecus, Australopithecus Afarensis, Australopithecus Africanus, Robustus, and Boisie.
After which, it is likely that due to a climatic change, the forests began to thin out to give way to a more open savannah; trees became few and far between. Thus, we had to move from one group of trees to another.
In order to cover these dangerous open spaces we began to adopt a more upright gait, as we were in a hurry to get from one tree to another because we were hunted; we were on the menu for any number of carnivorous animals that were both faster and more agile than us.
To survive we learnt that running was easier on two legs. We became more and more upright, passing out of the last Australopithecus stage, and into the first definition of Homo – that of Homo Rudolfensis and Homo Habilis; arguably the first tool user. We found bipedalism came with advantages, so we naturally evolved to make best use of these new survival traits.
Walking freed our hands for carrying food. Somewhere around then we discovered and mastered fire. We could frighten animals and chase them over cliffs. We became more the hunters and less, the hunted. An increased supply of meat meant an increased supply of protein, which in turn led to an ever-increasing brain size from just 400 cm3 to nearly 1,000 cm3. In the early Pleistocene, roughly 2 million years ago, our Homo kin hiked far and wide. It is likely that pockets of ‘Homo’ became cut off from each other by large bodies of water, mountains, varying habitats, or just plain distance. These disparate groups began to develop their own specialized traits. Most of these lines of evolution, in time, literally died out.
Spanning a million years, the various offshoots of our lineage came and went. Finally, about 1.4 million years ago, Homo Erectus came into being, and his brain size topped 950 cm3. As we moved through the ‘Homo’ phase, we were bipedal – when we became Homo Erectus, by the very definition we were ‘erect’. We were seriously upright; we were WALKING!
Somewhere on this timeline, we began the big hike out of Africa. Likely in several waves of emigration. Possibly driven by scarcity of food, the young needing to move on, and changes in climate and environment. Perhaps a combination of all three. Whatever the reason, some stayed behind and developed into Homo Sapien Sapien. Others moved out and colonized at first the near east, then Southern Europe and the far east, developing into Neanderthals and Denisovans.
Around 65,000 to 70,000 years ago Homo Sapiens began their own hike out of Africa. Possibly crossing a then more equitable Sahara Desert; through what is now Egypt and on into the Levant, and lastly even perhaps crossing at the horns of Africa into what is now Yemen.
We just kept on hiking, crossing vast tracts of land, and continents, even managing to overcome sea barriers to finally reach the furthermost places; Easter Island and the southern New Zealand Island about 1,500 years ago.
"Hiking is in our blood, it is instinctive, it is in our DNA. We need to hike, to look over that hill, to climb that top, to explore down that valley, wade up that river, to question boundaries." -Steve Chadwick