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[Home]
[Prog summaries - [Ice
World] [The
Earth was Born] [Out
of Eden] [In
perspective]]
[Out of chaos - [Introduction]
[Divine
guidance] [Tools
of knowledge] [Religious
conflict] [Search
goes on]]
[Survival - [Introduction]
[Exodus]
[New
Technology] [Moving
on]]
[The Globe - [Introduction]
[Star
Dust] [Water
of life]]
[Find
out more]
[Credits]
[Full site
with images]
The search for the origins of the planet take us from the hills of Western Australia, deadly caves in Mexico and the deepest mines in South Africa.
In its infancy, 4.6 billion years ago, Earth was a primeval hell — bombarded by billions of asteroids and comets, the surface scorched by ultraviolet radiation and volcanic eruptions spewed noxious gases into the primitive atmosphere.
But locked into its geology were the clues to its beginnings of life. The earliest forms, bacteria, had to harvest their energy from chemical reactions in the hellish broth they lived in. It was a world, in fact, very like the caves of Cueva de Villa Luz.
Moving to Jack Hill in Australia we find the earliest zircon crystals containing oxygen 18, showing the presence of large quantities of water at the earliest stages of our planet.
Even today, 40,000 tonnes of asteroids are ejected from their orbit and fall to Earth as meteorites every year. More than 70 varieties of amino acids have been found inside meteorites and eight of them are the fundamental constituents of proteins found in living cells.