Learning From Our Ancient Ancestors to Adapt to Climate Change and Resource Variability

By Jiya Chatterjee

Published in Horace Mann's Spectrum Magazine January 2021

Hundreds of thousands of years ago, the world looked a lot different. Hominids, primates that include Homo sapiens (humans), from the family Hominidae, roamed the lands of what is now modern-day Kenya, Africa. The food and water supply were plentiful in Africa, which is understood to be the place where humans originated. According to a new study led by Rick Potts of the Smithsonian Institute in Washington DC, around 400 thousand years ago, climatic variations had a direct impact on the behaviour of hominids. Potts’ team found evidence that the creatures living on the earth at the time were faced with new and extreme environmental changes. Numerous large animals died because they were unable to cope with the drastic climate fluctuations. However, the hominids, also known as ancient humans, were able to survive that period, and this study proves that hominids changed their traditional practices to new ones in order to adapt to climate variability.

Before the wave of harsh environmental changes, the hominids had a set way of life as a forager. In the acclaimed book “Sapiens”, by Yuval Noah Harari, he describes how the hominids had very diverse diets, and whenever they found food, the practice was to eat as much of the food available as possible. If a hominid came across a tree filled with fruits, it was expected that they would eat as much of it as they physically could before walking away. This is known as the widely accepted “gorging gene” theory, and is one of the many reasons why the hominids survived for tens of thousands of years, as they were able to survive longer just by eating one ‘meal’. In Potts’ study, the paper explains how the long-established lifestyle of hunter gatherers was also based on simple innovations such as Acheulean tools, which were comprised of sharp elongated stones to hunt animals. The majority of Acheulean tools that hominids used for hunting were from rocks that were found locally in their area. Anthropologists and paleontologists knew that about 400 thousand years ago, hominids began to change the materials they used for making such tools. They began to transition away from Acheulean tools made of local rocks to Middle Stone Age (MSA) tools using rocks found further afield. Different groups of hominids, all of which were spread across Kenya, began to trade with one another for different kinds of resources, including better quality of rocks. However, it was unclear to researchers why there were such changes in practices up until this new study by Potts. In essence, Potts and his team proved with paleontological evidence that environmental changes, such as sporadic volcanic eruptions, changes in water level and size of lakes, increased salinity in water, and variable humidity in soil, led hominids to behaviourally adapt to the harsh environment by changing their practices.

Potts’ team hired a drilling company in Kenya to extract layers of sediment deep within the Karoo Basin in order to look for evidence of environmental changes. Their sample contained sediment dating back to 1 million years ago, and it was an historic discovery, as there had never been a better environmental record found in Africa before Potts’ sample. When the sample was subjected to chemical and microscopic studies, it revealed a lot about what went on environmentally 400 thousand years ago. The researchers found evidence of faults created by frequent volcanic eruptions during that time period, as well as evidence of water shortage and lack of rainfall. They discovered that large basins and other large bodies of water began to dry up at about that time, and instead more small lakes and ponds began to form. The sample also showed that the vegetation of the area began to change from wooded forest to grass lands due to aridity, which also affected the animal population at the time. The faults from volcano eruptions reduced the size of grassy plains too, which were the main food source for large herbivorous mammals. The water shortage, change in landscape, and lack of food led to the extinction of many large mega-grazers, giving way to smaller-bodied herbivorous animals with more diverse diets, including pigs and antelopes. This sudden increase in small animals contributed to the changes made in toolmaking by the hominids, according to Potts’ study. For example, rock-based smaller spearheads that can kill small animals became more commonly used than the sharp elongated large stones used in the past.

The thesis in this study can also be explored from Harari’s perspective in his book Sapiens that talks about Homo sapiens from a much later time period. Harari explains that hunter-gatherers of the time were deeply aware of their immediate environment including animals, plants, weather and their own body and that helped them to adapt easily to environmental changes.

This study on ancient humans adapting to harsh environmental changes is relevant for what our approach to climate change should be in modern times. The study surmises that, “fundamental aspects of human adaptability had emerged by the time of our species’ African origin”. When faced with environmental challenges 400 thousand years ago, our ancestors chose to find innovative ways to deal with the changing surroundings, and these behavioural adaptations are one of the key reasons why humans are still around today. The hominids were able to survive what a lot of animals at the time could not, simply because they had deep knowledge of the surroundings and responded to the changing environment quickly. Climate change driven by global warming is occurring at a fast pace in today’s world, and yet we haven’t made as much progress as we should when it comes to adopting sustainable lifestyles and innovating and inventing ways based on science that would help us to adapt to climate change. Harari in Sapiens explains how “most people in industrial societies don’t need to know much about the natural world in order to survive. Although, our modern society collectively has more knowledge on our environment and climate, at individual level knowledge is limited to a tiny field of expertise for modern human beings.” While Pott’s study focuses on a specific group of hominids from 400 thousand years ago, there is much to learn and apply from that study; we should learn to adapt to ongoing climate change rather than being in denial of the phenomenon.

Sources:

Potts, R., et. al. (2020).

Increased ecological resource variability during a critical transition in

hominin evolution. Science Advances. https://advances.sciencemag.org/

content/6/43/eabc8975

Bower, B. (2020, October 21). Environmental changes may have helped make ancient

humans more adaptable. ScienceNews. Retrieved November 20, 2020, from

https://www.sciencenews.org/article/

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Harari, Y. N. (2015). Sapiens: A Brief History of Humankind.

HarperCollinsPublishers.