Human life - as we know it - evolved from our ancestor, homo erectus, 70,000 years ago in Africa. In essense, therefore, all of us - from blond Scandinavians to Australian Aborogines - have one parent: African.
The earliest humans migrated from Africa to Europe, Asia and (through the Bering Strait joining Russia and Alaska) to North America. Their features mutated along the way. In North Asia, "snow glare" led to, for example, the Chinese developing an extra fold under the eyelid as protection. Hence a narrow eye structure. In colder Europe, lack of sunshine led to skin mutations. Melanin cells (which give skin its colour) diminished to adapt to the climate. Hence pale skin.
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While our universe is 13.70 billion years old, the earth itself was formed just over five billion years ago. To get an idea of the enormity of the cosmos and the puny nature of human civilisation, let's compress 13.70 billion years of its evolution into one hypothetical 365-day, 12-month year.
According to legendary scientist Carl Sagan's cosmic calendar model, the Big Bang (which kicked off the cosmos) occurred on January 1, New Year's Day. Nothing much happened for the next four "months". On May 1, the Milky Way galaxy was born. Our solar system, which is one of the humbler, smaller members of the Milky Way's 350 billion stars, came into being a good four months later, on September 9.
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The Earth itself came along just five days later, on September 14. And eleven days after that, on September 25 in our compressed cosmic callendar, our very first biological ancestors, amoebae, made their formal bow. Things dawdled for a while after that. The first rocks formed on Earth around October 2 and the oldest fossils (bacteria and blue-green algae) came into being on October 9.
Then another lull for a couple of billion years while, presumably, the Gods were preoccupied. Finally, on November 1, an event of true earth-shaking dimensions occurred: the origin of sex by micro-organisms. Hereafter, living organisms acquired a gender and the bacterial version of Eve must have blithely raised a cell in celebration. On November 12, the oldest fossil photosynthetic plants saw the light of day and three days later, on November 15, eukaryotes (the first-ever cells with nuclei) made their debut.
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Now things get interesting in our 365-day cosmic calendar, compressed from the universe's 13.70-billion-year existence. On December 1, significant quantities of oxygen begin to develop on Earth, setting the ground for human creation. A fortnight later, the Earth's first worms are born and three days later, on December 19, the first fish begin to inhabit the sea.
Matters are beginning to heat up - literally. The sun is shining brightly and the first mammals arrive on land on December 21, followed two days later by reptiles. The first trees sprout on this day too. Then, on December 24, the legendary dinosaur makes his terrestrial debut. Four days later, the skies are populated with the Earth's first birds. By this time, December 28, the four-"day"-old dinosaur species becomes extinct… and the world's first flowers begin to bloom.
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The next two or three days, as the end of the cosmic calendar approaches, see feverish activity. The Gods are working overtime. The twenty-ninth day of December of our compresssed 365-day callendar witnesses the emergence of the first primates. The next day marks the evolution of giant new mammals (ancestors of today's elephants) and December 31, the last day of our cosmic calendar, experiences the Gods' creative tour de force, their cosmic piece de resistance - the birth of human beings.
The last day of December in our cosmic calendar is packed. In its twenty-four hours is compressed every event of the past several million years of human existence. Let's chronical these action-packed hours in more detail.
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By lunchtime, the Ramapithecus (an ape-like fellow who is thought to be our earliest ancestor) is grunting around in what is today known as East Africa (where every race on Earth evolved). He develops gradually, shedding hair and acquiring cognitive skills to evolve by 10.30pm that evening, way past dinner-time, into the first recognisable human being. Yes, the human race occupies precisely 1.5 hours - the last ninety minutes - of the cosmic year.
By 11pm, our ancestors have begun to use stone tools and at 11.46pm, "Peking Man" has domesticated fire. The most recent glacial period (the Ice Age) occurs at 11.56pm and, as late as 11.59pm, Europe is still inhabited by shaggy-haired, naked cavemen.
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The last sixty seconds of our cosmic year are pacy and have to be broken up into seconds. At 11.59.20pm, agriculture is invented (in more conventional terms that was 6,000 years ago - thus these last few seconds contain the events of six millennia). The first cities and the Neolithic civilisation arrive at 11.59.35pm. And the dynasties of Egypt and Sumeria are founded ten seconds before zero hour (the present). At 11.59.53pm, the Trojan war breaks out and the Mycenean culture is founded. The next second sees the first Assyrian empire, and the founding of Carthage by Phoenicia.
At 11.59.54pm, Lord Buddha is born, Emperor Ashoka rules India and the Chin dynasty reigns over China. Christ is born at 11.59.56pm and the Roman Empire falls one second later. At 11.59.58pm, the Byzantine empire is founded, Mongol conquests begin and the Crusades are fought in Europe. The penultimate second in our compressed cosmic calendar witnesses the effloresence of the Renaissance in Europe, the emergence of experimental science and the birth of the Chinese Ming dynasty.
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The stroke of midnight represents the discovery of America, the industrial revolution, the growth and decay of European colonial empires in Asia, Africa and South America, and the two World Wars. And the very last split second of our cosmic year represents man's exploration of outer space, nuclear weapons, advanced computer technology and the internet.
That's it - the history of our 13.70 billion-year-old universe compressed in a twelve-month calendar year. It shatters cosy human notions to discover that, in such a cosmic year, the Earth does not come into existence till September; that dinosaurs emerge on Christmas eve, that primitive men and women originate at 10.30pm on New Year's eve, and that all of our recorded history occupies the last ten seconds of December 31. Humans come into being in the last hour of the entire cosmic-compressed year. Civilisation, in cosmic terms, is literally a few seconds old.
What this little exercise also teaches us is that we should stop taking ourselves too seriously. Life is short - in more ways than one.