Geological Time

If the world were an woman … we could call her Gaia … aged 44

Let's set a scale of 2 million years = 1 Gaia week, so 104 million years = 1 year. And sure enough, in round numbers, 44 Gaia years = 4.6 billion years which is our current scientific understanding of the age of the Earth. At the other end of the scale, 6,000 years which encompasses all of written human history = ½ a Gaia hour

Gaia tells the story of her life

‘First simple cells appeared at age 9 but I had not acquired my green colouration until I was 15 and learned how to photosynthesize. It took another 9 years though, for me to get an oxygen atmosphere and by the time I was 25 more complex cells started to appear. Not till I was 35 did these begin to group together to first form multi-cell life forms. My late 30’s saw the first insects, fish and land plants and my early 40’s saw amphibians and reptiles. At age 42 came the first dinosaurs – and the first mammals. Birds followed and then flowers the year after. The dinosaurs died out around the time I turned 44, finally giving a chance for the mammals to flourish.

Things have got interesting in the last ten days; a few brainy biped types have learnt to make fire and stone tools and yesterday started forming more complex societies, art, music. The more northern, thicker browed type died out two hours ago and the survivors, the ones that emerged from the large southern tropical continent have named, for themselves, this last half-hour “all of recorded history” ‘