The Earth is thought to have formed at 4.6 billion (4600 million) years ago, however there is evidence of primitive life as early as 3.9 billion years ago, just after the molten globe hardened, the oceans formed, and the asteroid bombardment stopped.
Complex life began to emerge only in the past 500 million years or more, accounting for just around 12% of Earth’s history.
While our ancestors have been around for about six million years, the modern form of humans only evolved about 200,000 years ago. Civilization as we know it is just roughly 6,000 years old, and industrialisation began in earnest only in the 1800s. While we’ve done a lot in a short period of time, it also highlights our responsibilities as stewards of the only planet we now inhabit.
The impact of people on the planet cannot be overstated. We’ve survived in extreme places like Antarctica. Every year, we cut down forests and ruin other natural places, forcing species into smaller regions or endangering them due to the need to construct more houses to accommodate our rising population.
With seven billion people on the earth, pollution from industry and transportation is a major contributor to climate change, which impacts our planet in unpredictable ways. However, the repercussions are already seen in melting glaciers and increasing global temperatures.
According to the Smithsonian Institution, the earliest concrete connection to humans began roughly six million years ago with a monkey group known as Ardipithecus. This African population pioneered upright walking. This has long been seen as significant since it allowed for greater free use of the hands for toolmaking, armament, and other survival necessities.
The Australopithecus group, according to the museum, emerged between two and four million years ago, with the ability to walk upright and climb trees. Then came Paranthropus, which lived between one million and three million years ago. The group is marked by bigger teeth, which allow for a broader diet.
According to the museum, the Homo group, which includes our species, Homo sapiens, first appeared more than two million years ago. It is marked by larger brains, increased tool-making, and the capacity to move far beyond Africa.
Our species emerged some 200,000 years ago and managed to survive and develop despite climatic change at the time. While we originated in temperate temperatures, some 60,000 to 80,000 years ago, the earliest humans began venturing outside of the continent where our species was created.
To put that into perspective, the genesis of our species, Homo sapiens, dates back around 300 thousand years ago, which similarly seems to be a long time ago, but represents just 0.007 percent of the planet’s whole history (4.5 billion years)!
The Archaean, which spans the period between 3800 and 2500 million years ago, is the middle epoch of Precambrian time. The presence of fossil bacteria in rocks considered to be 3500 million years old indicates that life first appeared on Earth during the early Archaean.
The earliest human ancestors arose between five and seven million years ago, most likely when some apelike animals in Africa evolved to walk on two legs. They were flaking primitive stone tools by 2.5 million years ago. After two million years, some of them migrated from Africa into Asia and Europe.
Humans looked approximately the same 10,000 years ago as they do now, with small variances in height and shape owing to dietary and lifestyle differences. However, in the next ten millennia, we may have developed genetic ‘editing’ procedures to ensure that all of our offspring are born attractive and healthy.
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