Made from igneous, metamorphic, or other sedimentary rocks. When these rocks are exposed at the earth’s surface they begin the long slow but relentless process of becoming sedimentary rock. First sedimentary rock found in Greenland 3.8 billion years ago.
First Blue and Green Algea
3,400,000,000 BC - 04/16/2013
The first bacteria was cyanobacteriabacteria, cyanobacteria are larger than most bacteria, and may secrete a thick cell wall. More importantly, cyanobacteria may form large layered structures.
3.4 billions years ago.
Communities of Organisms form "mats"
2,700,000,000 BC - 04/16/2013
Microbial mats are specialized microbial communities that are composed mainly of photosynthetic prokaryotes.
Evidence of Microbial Life
2,100,000,000 BC - 04/16/2013
Carbon isotopes and fossil stromatolites are the evidence to early microbial life.
Eukaryotic Emdosymbiosis Occurs
1,400,000,000 BC - 04/16/2013
Large cells are present suggesting eukaryotic emdosymbiosis has occur and sexual reproduction is now present. 1.4 billion years ago.
First Known Multicellular Organisms Form
1,200,000,000 BC - 04/16/2013
First known multicellular organisms are formed. Are very jelly-fish like. 2.1 billion years ago.
Beginning of the Cambrian period and first abundant fossils
550,000,000 BC - 04/16/2013
Fossils from species like brachiopods, tribolites, anthropods are formed. 550 million years ago.
Beginning of the Ordovician period and first backboned animals
500,000,000 BC - 04/16/2013
During this time period most continents came together to form super-continent Gondwana, also the first sea animals came to land; horse shoe crabs began to mate and spawn on land. 500 million years ago.
Beginning of the Silurian period and the first land plants
440,000,000 BC - 04/16/2013
Corals and other marine organism thrived, also first land plants; didn’t have leaves at first but then turned into mosses and ferns. 440 million years ago.
Beginning of the Devonian period and the first amphibians
400,000,000 BC - 04/16/2013
Many fish and amphibians appeared during this time period; ray-fish and lobe-finned boney fish are examples. 400 million years ago.
Coal Age Forests
350,000,000 BC - 04/16/2013
Giant spore producing trees are abundant. 350 million years ago.
The First Reptiles
345,000,000 BC - 04/16/2013
During carboniferous period, evolved from water animals; Hylonomous is the oldest know reptile. 345 million years ago.
Beginning of the Permian Period
285,000,000 BC - 04/16/2013
Last period of the paleozoic era, largest mass extinction recorded in history of earth, Pangea was formed. 285 million years ago.
Beginning of the Triassic period and first dinosaurs
245,000,000 BC - 04/16/2013
Started after mass extinction, beginning of Mesozoic Period and age of reptiles, dinosaurs evolved from archosaurs (lizard type things). 245 million years ago.
Beginning of the Jurassic period and first mammals
205,000,000 BC - 04/16/2013
Pangea starts to drift apart, and many dinosaurs and first birds start to appear. 205 million years ago.
150,000,000 BC - 04/16/2013
Jurassic period, developed from dinosaurs, Aves was the biological class these birds were in. 150 million years ago.
Beginning of the Cretaceous Period
140,000,000 BC - 04/16/2013
Warm climate and many shallow inland seas. New birds, mammals, and flowering plants appeared. Many dinosaurs stayed on land and reptiles were in the water. 140 million years ago.
Massive extinction which ends the age of the dinosaurs
65,000,000 BC - 04/16/2013
Cretaceous-Tertiary (K/T) Extinction Event. This may have been caused by an iridium-rich meteorite or comet hitting Earth and causing dust to block out the sun. 65 million years ago.
First primates and mammals diversify
60,000,000 BC - 04/16/2013
Mammals/primates develop different characteristics. Ex: flat nails, thumbs, better vision. 60 million years ago.
First Elephant-like Animals
38,000,000 BC - 04/16/2013
Phosphatherium, small pig sized elephant. 5 million years after dinosaurs went extinct. 38 million years ago.
Camel, horse, big cat and new species on grasslands
30,000,000 BC - 04/16/2013
The animals crossed the ice bridge to Eurasia, and then dispersed to North America. 30 million years ago.
Beginning of the Pliocene Epoch
5,000,000 BC - 04/16/2013
This was a time of global cooling after the warmer Miocene. The cooling and drying of the global environment may have contributed to the enormous spread of grasslands and savannas during this time. The change in vegetation undoubtedly was a major factor in the rise of long-legged grazers who came to live in these areas.
FIrst human like animals
2,000,000 BC - 04/16/2013
Studies show we are related to an ancestor that looked like a squirrel. The ankle bones show that it had a mobile ankle joint like primates today that live in trees. 2 million years ago.
Beginning of the Pleistocene epoch and ice ages
1,000,000 BC - 04/16/2013
Many genera and even species of Pleistocene conifers, mosses, flowering plants, insects,mollusks, birds, mammals, and others survive to this day. Yet the Pleistocene was also characterized by the presence of distinctive large land mammals and birds.
Last ice age
10,000 BC - 04/16/2013
Around 130,000-110,000 years ago the Earth's climates were generally much like those of today, though somewhat warmer and moister in many regions. As the cold grew more severe, the Earth's climate also became drier because the global 'weather machine'.
10,000 years ago.