The words Climate Change and Global Warming are often bandied about. Phenomena, deadly enough to wipe out our entire species and yet, in popular perception, far enough into the future to not warrant any immediate remedial action. If our planet’s long history of 4.5 billion years could be condensed into a single 24 hr day, the modern human has been a part of that history for less than 3 seconds and yet, our impact has been one of the most influential.
But in order to understand why, we need to take a quick dive into the past; into our extensive and yet, relatively short history as inhabitants of this planet. For even though the past cannot change, the knowledge we have about it and the way we look at it, is constantly changing.
Our journey into the history of our species begins with a relatively recent discovery, that of the fossil Sahelanthropus in Chad, Africa. The fossil, discovered at the start of the 21st Century, dates back almost 7 million years and is believed to be our oldest ancestor. It’s discovery has helped scientists better understand the long evolutionary journey that led to the creation of the modern human.
It is believed that our story begins in Africa, where diverse groups of early humans, driven by changes in the Earth’s climate, interacted to generate the unique genetic make up of modern humans.
The modern human, i.e homo sapiens evolved only around 200,000 years ago, in what we now call the Middle Stone Age. This era saw great advancements in the types and ways stone tools were manufactured and used, which significantly altered the nature of our interaction with the surrounding environment since we were now more lethal hunters and thereby, acted as a catalysing agent in the process of our evolution.
The period that followed witnessed the first great human migration. Drastic changes in the Earth’s climate and landscape, specifically lower sea levels, enabled the passage of early humans out of Africa through the middle east and into the rest of Eurasia. These climatic changes were characteristic of the Pleistocene Epoch, a period during which a succession of glacial and interglacial climatic cycles took place, ultimately ending in the Holocene Interglacial or Holocene era.
This period, which followed the Pleistocene, was characterised by warmer and more stable conditions. It was during this period, beginning close to 12,000 years ago, that mankind’s activities grew into a sizeable geological and morphological force, allowing the development of modern civilisations as we know it.
Now, as our period of relative stability begins to waiver due to rising temperatures, we are witnessing the end of the Holocene and the start of a new epoch- the Age of Anthropocene.
Over the past 250 years, since the dawn of the Industrial Revolution, the world has enjoyed an era of prosperity and development. Due to great technological and medical advancements, mankind’s impact on the Earth has increased manifold, outweighing even the impact of many natural processes. This means that human beings have now become the most significant geological force on the planet- a frightening thought!
In the past, the biggest threat to the survival of a species were drastic changes to the Earth’s climate as a result of natural, unavoidable disasters such as asteroids and volcanic eruptions. For the first time in history, this is no longer true. The climate change we refer to today is unlike that of the past. It is purely man made. Unnatural. A result of greed.
Humans have such power to impact the natural world, that we find ourselves at the hinge of history. Our actions have a lasting, likely irreversible impact on the Earth’s systems and processes.
What we do in our lifetime will determine the future of mankind.