Human Evolution: The start

The Start of Human Evolution: Australopithecines

Deep in Africa;
something began to stir.

Picking the “start” of human evolution is a silly thing to try and do. The Universe formed, life started on Earth, it grew a backbone, the first mammals evolved etc. The idea of some particular animal, a magical “missing link” between humans and the rest of life on earth is also silly. There are lots of animals in between us and the rest of life, each fossil gives us another equally important link in the cage.

However, if you were to pick an animal, something that was roughly halfway between chimpanzees, our closest surviving relatives, and humans you would probably pick Australopithecus Afarensis. Let’s dive in.

Australopithecus Afaransis: The start of human evolution

Australopithecus Afarensis – one of the earliest human ancestors that lived roughly 3.3 million years ago. They could walk upright and probably spent a fair bit of time out of trees. But they probably couldn’t run, and still had a lot of body hair and a very chimpanzee-like face (Image: Artist’s rendering from Encyclopedia Britannica).

Australopithecus Afarensis was an early human ancestor that lived roughly 3 million years ago in Africa. They had a large amount of body hair, flared nostrils, and a thick jaw, much like a chimpanzee and a small crest in the center of their head, like a gorilla. However, they also walked upright (albeit a bit awkwardly) and their feet have started to evolve for running, as opposed to grasping trees. They were a fair bit bigger than chimpanzees standing somewhere between 140 to 160cms. They also seemed to live in almost any environment in early Africa, woods, grassland, savannas, swamps and ate almost anything, nuts, berries, grains and meat if they could get it. They were certainly not top of the food chain and were regularly hunted, but they did use some very basic tools (rocks that had a bit of an edge chipped into them – see below).

The most famous Australopithecus is Lucy. She was a very short Afarensis discovered in South Africa. She is particularly famous for being an almost complete skeleton, giving scientists a lot of information about the species. She was named Lucy because the Beatles song “Lucy in the Sky with Diamonds” was playing at the moment she was initially unearthed in the Awash Valley in Ethiopia. In the local Amharic language, her fossil is known as the “Dinkinesh”, which translates to “you are marvelous”. Lucy was a bit short for her species, only 105cm and 45 kg and pretty young and likely had not had any children.

One of the most interesting things about Afarensis is its brain. Human brains are one of the most unique things about our species – we have massive heads compared to almost every other animal. From the time of Lucy to modern humans over about 2 million years, the size of the human brain roughly doubled. How and why this happened is still a bit of a mystery. Brains are really expensive, they take a lot of energy to run. Afaranesis’s brain is still very similar to a chimpanzee, very sophisticated, but the explosion in brain capacity that lead to modern humans had yet to take place.

Finally, there are other similar animals to Australopithecus afarensis. There is a whole category of these animals, roughly midway between humans and apes called “Australopithecines” – we know about twenty of them. They are all similar, in that they had started to walk upright, a bit awkwardly, but still had thick monkey-like faces and long arms for swinging around in trees. Afarensis is the one that is best understood, some of the others we only have a few fragments for. Some of our favorites at the Universal Story are:

paranthropus – a more stocky, gorilla-like ape with a thick skull and jaw, probably for cracking nuts;
amanensis – a direct ancestor of afarensis, probably lived more in woodlands and ate a more plant and fruit based diet similar to chimpanzees; and
africus – the first one ever discovered, that Charles Darwin had as the first evidence that we evolvedin Africa – potentially even older than afarensis, and the oldest fossil we have between chimpanzees and humans.

These are the tools that were used by Australopithecus Afarensis roughly 3 million years ago. They were found in Ethiopia and are some of the earliest recognizable tools created. They are part of what is referred to as the “Oldowan” or “Mode I” stone tool industry, named after the site in Tanzania where the tools were first found in the 1930s. There is a distinct beauty to these tools – they are humanity’s first attempts to really shape our world. See our posts on early human tools here (Image: D Descouens).

Why is Australopithecus Afaransis the start?

*A reconstruction of the head of an Australopithecus africanus — a human ancestor — on display in the Hall of Human Origins in the Smithsonian Museum of Natural History in Washington, D.C*.

There are a lot of different things you could choose to indicate the “the start” of our common humanity. We are going to talk about them all, here at The Universal Story over. Obvious choices are rock art, and cave paintings tools and written language – and there are many others.

However, we don’t think any of those are the best choice. Years ago, anthropologist Margeret Mead was asked what she considered to be the earliest sign of “civilization” in a culture. She was presented with all the obvious options – art, tools, fire and she was expected to one of those answers. However, she responded the first sign of civilization was “a healed broken thigh bone”. This puzzled her audience. Broken bones are normally evidence of violence not civilization. Mead then explained that if you break your femur, without modern medical equipment, you basically always die. You cannot hunt or gather food, you cannot find water, you cannot run from danger. You are meat for hungry beasts.

The only way for someone to survive a broken femur is that other people helped them. And this is the real fundamental element of humanity and civilization. Taking care of the vulnerable and building trust so things can be built together. And this, is the essence of civilization.

It is hard to tell if Australopithecines often survived broken femurs. The bones in fossils are almost universally broken and it’s hard to tell if this happened during their life or to their skeleton after death. However, one thing we do know about Australopithecines is that they gave birth to very large young. This meant that it took a long time and was a significant investment of resources. The young were probably helpless for a period, like human babies. And, because of the size of their heads, it meant childbirth was almost certainly very dangerous for their mothers, with significant numbers of them dying. This is backed up in the fossil record with groups of Australopithecines having surprisingly large numbers of juveniles and infants. It’s very likely many of them were orphans.

Combined together, this means that Australopithecines almost certainly cared for each other’s young as a tribe. It takes a village, and Australopithecines built the first villages. Frankly, this is something, not even a lot of modern human societies manage to do. So if we are looking for the point, where the human journey started, where the best of what we can be started to emerge, our pick here at The Universal Story is Australopithecus Afarensis.