Appendix 7: Timescales
A compressed time line of the Universe from 13.7 billion years to 13 days is as follows:
If the Universe had begun 13 years ago, then at this moment …
The Earth would have existed for about 5 years
Large organisms would have existed for about 7 months
The asteroids that killed off the dinosaurs would have landed about 3 weeks ago
Hominids would have existed for just 3 days
Our own species, Homo sapiens, would have existed for 53 minutes
Agricultural societies would have existed for 5 minutes
The entire recorded history of civilisation would have existed for 3 minutes
Modern industrial societies would have existed for 6 seconds
Source: David Christian, “World History in context”, Journal of World History, December 2003, 440
Homo sapiens has therefore been around for the equivalent of 53 minutes in a comparative period of 13 days!
Another way of looking at this is to consider the matter on the basis of a 24 hour cycle, as Steve Jenkins has done in his excellent book for children entitled Life on Earth – The Story of Evolution, thus:
Midnight: Earth forms
4.47 am Life (first single cells) appear
8.48pm First multi-celled organisms appear
9.52 pm Life moves to the land
10.42 pm First dinosaurs and mammals evolve
11.39 pm Dinosaurs become extinct; flowering plants appear on land
11.38.30 pm (1 ½ mins before midnight) – Early humans found in Africa
11.59.58 pm (2 secs before midnight) – Modern human appear.
Modern humans have been around for a mere 2 seconds on a compressed timescale of 24 hours!
If the Universe had begun 13 years ago, then at this moment …
The Earth would have existed for about 5 years
Large organisms would have existed for about 7 months
The asteroids that killed off the dinosaurs would have landed about 3 weeks ago
Hominids would have existed for just 3 days
Our own species, Homo sapiens, would have existed for 53 minutes
Agricultural societies would have existed for 5 minutes
The entire recorded history of civilisation would have existed for 3 minutes
Modern industrial societies would have existed for 6 seconds
Source: David Christian, “World History in context”, Journal of World History, December 2003, 440
Homo sapiens has therefore been around for the equivalent of 53 minutes in a comparative period of 13 days!
Another way of looking at this is to consider the matter on the basis of a 24 hour cycle, as Steve Jenkins has done in his excellent book for children entitled Life on Earth – The Story of Evolution, thus:
Midnight: Earth forms
4.47 am Life (first single cells) appear
8.48pm First multi-celled organisms appear
9.52 pm Life moves to the land
10.42 pm First dinosaurs and mammals evolve
11.39 pm Dinosaurs become extinct; flowering plants appear on land
11.38.30 pm (1 ½ mins before midnight) – Early humans found in Africa
11.59.58 pm (2 secs before midnight) – Modern human appear.
Modern humans have been around for a mere 2 seconds on a compressed timescale of 24 hours!