The evolution of humans is an incredible journey. The changes that occurred in the physical development of our early ancestors were triggered by changes in their environment and diet. These were the first steps that enabled humans to become the most successful species on the planet and migrate to all corners of the world. Each migration led to new adaptations which allowed them to not only survive but thrive.
But we were not the only humanoids to evolve. Homo sapiens was just the only one to outlive the others. Are you ready to find out how?
In this book summary readers will discover:
- The adaptations that allowed our ancestors to evolve
- The other humanoid species
- Thinking allowed Homo sapiens to flourish
Key lesson one: The adaptations that allowed our ancestors to evolve
It’s hard to believe that a change in climate started it all but seven million years ago, that’s exactly what happened. The changes led to the African rainforest becoming savannas that had less tree and more grasslands. The apes that had been accustomed to living, escaping predators and finding food in the trees of the rainforest were now left out in the open.
However, some of the rainforest apes developed a big toe that was not curled due to a genetic mutation. This mutation turned out to be beneficial as a straight big toe enabled them to walk upright. Walking upright meant that the apes could now spot predators and prey in their environment. They could also now run and change directions quickly. These allowed them to adapt and survive in their new environment.
Our primate ancestors also had another advantage – their brain size. Living in this new environment meant that they had to be strategic to survive. They had to evade predators and find new sources of food. As much as the fruits and nuts they had foraged previously in trees provided the calories for the brain development up until then, they found a new source of food. They could hunt in the savanna and therefore obtain meat. This was a food source that was new to them but provided them with the calories to further encourage their brain development.
This new diet of meat produced a positive feedback loop. Eating meat led to larger brains that then led to an increased ability to hunt, get more meat and obtain more energy to enable further brain development. To give you an idea of the size, a savanna primate had a brain capacity of approximately 450-500cc. That is almost 25-40 per cent larger than a chimpanzee. In comparison, Australopithecines, another primate at the time kept its diet of fruit and nuts. The brains of this species did not develop in the same way as the other meat-eating primates.
The other advantage that our ancestors had was actually a consequence of the previous adaptations. When apes began to walk upright, their bodies changed drastically. Firstly, walking upright changed the pelvic area and they ended up with narrower hips. Secondly, larger brains meant larger heads. These two new features meant that childbirth was a bit of a problem going forward. Narrow hips resulted in a smaller birth canal for a baby with a larger head.
An evolutionary adaptation to deal with this resulted in primates having a shorter gestation period meaning that the babies were born earlier. Being born earlier meant that the baby’s head was still small enough to fit through the birth canal. This is an adaptation that we still have today as humans. If a human baby were to be born with the same brain size as a baby gorilla, the gestation period would have to be 20 months! Human babies continue their brain development outside the womb for about a year.
Being born early also provided our ancestors with a surprising advantage. They developed the ability to learn as they grew – an ability we still possess. Learning from a young age when the brain is still malleable was crucial to our success as a species. As humans grow they developed skills, built tools and adapted to their surroundings. Other primates have brains that develop in a year thus depriving them of more time to learn.
Key lesson two: The other humanoid species
When primates began to leave Africa 1.9 million years ago, they were not our direct ancestors, Homo sapiens. Instead, they were another species of early primates, Homo erectus. Homo erectus was able to move out of Africa and cover long distances. They were found in Arabia, Asia, Indonesia and Europe. Even more incredible was the fact that they adapted to these new locations, developing stone tools and harnessing fire. This showed that as they moved into new environments with differing conditions from their original habitat, they could adapt to survive.
Homo erectus wasn’t the only humanoid species to travel out of Africa. There has been evidence found over the years that show that others did too. In Siberia, evidence was found of a species referred to as the Denisovans. Homo sapiens share a common ancestor with Denisovans and there is also genetic evidence of interbreeding between the two species. In fact, people from Papua New Guinea and Bougainville Island still have some Denisovan DNA present in their genome.
Homo floresiensis is another species that has been found on an Indonesian island. These humanoids were skilled hunters and had also mastered fire. They were, however, under four feet tall and had very small brains. You might think that small brains should not have enabled them to adapt the way they did to island-living but some researchers believe that their small size was a result of island-dwarfing. They got smaller because of their environment but still retained their brainpower. Interestingly enough, although it is believed that Homo floresiensis died out 17 000 years ago, there are still some who believe that they might actually be alive and living in areas of unexplored jungle in Indonesia.
Homo heidelbergensis is thought to be the common ancestor of Homo neanderthalis and Homo sapiens. When Homo heidelbergensis left Africa and entered Europe they gave rise to Homo neanderthalis more commonly referred to as Neanderthals. They were better adapted than other species to survive the cold climate of Europe and had large brains. Their hunting strategies were complex and involved them working together as a team. It is known that they liked to hunt mammoth by surrounding the animal and herding it off a cliff. Thus, they had group strategies and were able to communicate thus having some sort of common language.
They also built homes, performed rituals when someone dies and cared for those that were ill or injured. The Neanderthals possessed one flaw though which made them not as successful as humans, they reached adulthood too early. Neanderthals were classified as adults by the time they reached 15. This meant that they had fewer years as compared to Homo sapiens to learn. Scientists believe that they reached adulthood faster because of the harsher climate they had to survive in. However, it is also the main reason that they were unable to survive longer.
Key lesson three: Thinking allowed Homo sapiens to flourish
Did you know that there was a brief time in history when Homo sapiens almost became extinct? About 70 000 years ago, an ice age and volcano eruption blocking the sun resulted in there being an estimated 10 000 Homo sapiens left. So, how exactly did they manage to survive and become the most successful species on the planet?
Well, it’s because Homo sapiens could not just think, but think symbolically. You see, at the time when Neanderthals were dying out, humans were making jewellery. This may seem like a trivial comparison but the fact that Homo sapiens could make patterned jewellery from rocks and shells shows that there was a significance behind them. This was a huge evolutionary leap. Symbolical thinking enabled humans to develop language and become self-aware. They could use symbols to communicate amongst each other and develop written language. The development of art was a further sign that Homo sapiens could think symbolically. This type of thinking made our ancestors aware of themselves and their behaviour allowing them to reflect and change depending on the need.
This is what allowed Homo sapiens to survive and thrive when they were on the brink of extinction. When they moved out of Africa for the first time, it is highly likely that they came across other species as they spread across the globe. These were species that left Africa before they did. There is genetic evidence that even shows that they likely interbred with some of these species including Denisovans and Homo neanderthalis. It is also highly likely that they fought each other when they crossed paths. There has been evidence found in Europe that Homo sapiens and Homo neanderthalis not only fought but ate each other too.
Homo sapiens did not battle their way to becoming the last ape standing though. It is most likely that they were just more adept at adjusting to their environments. Their ability to think symbolically and communicate with each other enabled them to be better hunters than the other species. They basically out-performed the other species and that probably contributed to their demise as Homo sapiens took over their habitats. When all other humanoids disappeared from existence, our ancestors remained. They thrived and continued their evolutionary development and invented farming and the beginning of civilization as we know it.
The key takeaway from The Last Ape Standing is:
Homo sapiens have come a long way to become the most dominant and successful species on the planet. There were many other humanoid species that also developed alongside Homo sapiens but they lacked one thing, our ability to survive. This ability to survive is based predominantly on our long childhoods. This gave our ancestors more time to learn and for their brains to develop. In turn, humans began to think symbolically and communicate which further aided their capabilities.
How can I implement the lessons learned in The Last Ape Standing:
Our early ancestor’s abilities to learn and develop throughout childhood is something that we still possess today. A child’s formative years are crucial for development and thus should not be overlooked. Encourage your child’s learning and creativity. It is how our ancestors thrived and how we are still able to thrive today.
