Canonical Milestones

From The Limits of Complexity by Theodore Modis, an attempt to define and measure complexity. Modis attempts to identify the most significant milestones in history: "The 28 'canonical' milestones, . . . generally represent a cluster of many milestones events." See the article for his methodology which is necessarily open to criticism, but it is an interesting attempt. Below are the 28 inflection points of history which he identifies from a larger complilation from a variety of sources.

1) The Big Bang and associated processes: 15.5 billion years ago

2) Origin of Milky Way, first stars: 10 billion years ago

3) Origin of life on Earth, formation of the solar system and the Earth, oldest rocks: 4 billion years ago

4) First eukaryotes, invention of sex (by microorganisms), atmospheric oxygen, oldest photosynthetic plants, plate tectionics established: 2 billion years ago

5) First multicellular life (sponges, seaweeds, protozoans): 1 billion years ago

6) Cambrian explosion, invertebrates, vertebrates, plants colonize land, first trees, reptiles, insects, amphibians: 430 million years ago

7) First mammals, first birds, first dinosaurs, first use of tools: 210 million years ago

8) First flowering plants, oldest angiosperm fossil: 139 million years ago

9) Asteroid collision, first primates, mass extinction (including dinosaurs): 54.6 million years ago

10) First hominids, first humanoids: 28.5 million years ago

11) First organutan, origin of proconsul: 16.5 million years ago

12) Chimpanzees and humans diverge, earliest hominid bipedalism: 5.1 million years ago

13) First stone tools, first humans, Ice Age, Homo erectus, origin of spoken language: 2.2 million years ago

14) Emergence of Homo sapiens: 550,000 years ago

15) Domestication of fire, Homo heidelbergensis: 325,000 years ago

16) Differentiation of human DNA types: 200,000 years ago

17) Emergence of "modern humans," earliest burial of the dead: 105,000 years ago

18) Rock art, protowriting: 35,800 years ago

19) Invention of agriculture: 19,200 years ago

20) Techniques for starting fire, first cities: 11,000 years ago

21) Development of the wheel, writing, archaic empires: 4,907 years ago

22) Democracy, city-states, the Greeks, Buddha: 2,437 years ago

23) Zero and decimals invented, Rome falls, Moslem conquest: 1,440 years ago

24) Renaissance (printing press), discovery of New World, the scientific method: 539 years ago

25) Industrial revolution (steam engine), political revolutions (France, USA): 250 years ago

26) Modern physics, radio, electricity, automobile, airplane: 100 years ago

27) DNA structure described, transistor invetned, nuclear energy, World War II, Cold War, Sputnik: 50 years ago

28) Internet, human genome sequenced: 5 years ago