Origin of the solar system Earth forms, 4.6 B.Y.B.P. Oceans form, 4.0 B.Y.B.P Primitive algae evolves, 3.3 B.Y.B.P First fossil evidence of multicellular organisms, 1.2 B.Y.B.P. Trilobites are abundant, algal reefs form, 600 M.Y.B.P. First corals evolve, invertebrates dominate oceans, 500 M.Y.B.P. First land plants evolve, insects appear, 440 M.Y.B.P. Fishes are abundant, early amphibians evolve, 400 M.Y.B.P. Forests that become coal swamps are present,300 M.Y.B.P. Earliest reptiles evolve, 300 M.Y.B.P. Alleghenian Orogeny occurs, 270 M.Y.B.P. Trilobites become extinct, 270 M.Y.B.P. Earliest dinosaurs appear, 225 M.Y.B.P. Pangaea breaks up, 225 M.Y.B.P. Earliest mammals evolve, 200 M.Y.B.P. | Dinosaurs are abundant, 180 M.Y.B.P. The first birds evolve, 180 M.Y.B.P. Asteroid impact, 66 M.Y.B.P. Modern groups of mammals appear, 60 M.Y.B.P. Earliest horses evolve, 60 M.Y.B.P. Large mammals evolve, 40 M.Y.B.P. Carnivores abundant, 11 M.Y.B.P. Adirondack mountains uplifted, 11 M.Y.B.P. First humanoids evolve (Australopithecus africanus), 3 M.Y.B.P. Ice Age of the Pleistocene begins, 1 M.Y.B.P. Mammoths and mastodons are abundant, 1 M.Y.B.P. Large ice sheets retreat ~ 10 000 years ago Mount Vesuvius erupts and destroys Pompeii, A.D.79 New Madrid Earthquake, 1811–1812 Chicago Fire 1871 Krakatoa eruption in Java, 1883 Chicago Bull win 5th World Championship, 1997 |