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Big Bang
About 13.7 Billion years ago all the matter in the universe was compacted into an extremely tiny point. This point rapidly expanded into an explosion and is still expanding today. Some evidence that backs this up is that we know the galaxies are moving away from each other, and the furthest galaxy is moving away at the fastest speed which shows that it is still expanding. -
First stars are born
Astronomers have discovered that the first stars were formed approximately 550 million years after the big bang. Astronomers can predict this by looking at the most ancient light in the universe, as stars were the first form of light. -
First galaxies form
The first galaxies were thought to have formed 500 millions years after the big bang, but recently scientists have found a galaxy further away that looks to have formed 300 millions years earlier. Because scientists now have better technology, new discoveries are made more often so there is a possibility there may be a galaxy that formed earlier than this. -
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The milky way galaxy forms
The milky way started forming 12 to 13 billions years ago or roughly 500,000 years after the big bang. After this the Universe cooled for a bit and all there was, was gas spread throughout. The gas slowly came together and become large enough clumps, heating up and starting the nuclear fusion that powers stars. The Milky Way is often referred to as a cannibal galaxy, because during formation it swallowed up smaller galaxies. to get bigger. It is believed that most other galaxies do this aswell. -
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The solar system forms
The solar system that we live in consists of a medium sized star (the sun) with 8 planets orbiting it. About 5 billion years ago, a giant cloud called a nebula was floating in our galaxy. This cloud began to collapse and the atoms separated and began to bounce off each other generating a lot of heat. Eventually, they reached a temperature at which the atoms began to fuse, in a process called nuclear fusion. As they did a tiny bit of matter transformed into a lot of energy, and our star was born. -
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First single celled organisms
We don't know exactly when life first appeared on earth. What we do know is that 3 billions years ago there was definitely some form of life. There are some rocks that were around 3.8 million years ago that have marks on them that scientists believe could have been made by primitive microorganisms. If this is true then life on earth originated soon after the meteorite attack. -
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First multi-celled organisms
multi celled organisms evolved from single celled organisms about 2 billion years ago. More than 250 fossils were recently found in Gabon. Until recently it was believed that complex life forms dated back 600 million years ago. -
First animals with shells and hard parts
The fossil remains of the first animals with shells date to about 520 millions years ago. Some scientists in Santa Barbara analyzed these fossils called the Early Cambrian. They also found out that there was a huge diversity of animal life in the ocean at that time and that many of the major animal groups that are still alive today also appeared then. -
First vertebrates
The first vertebrates were fish in the ocean and were around approximately 500 millions years ago. Being vertebrates means that they have a backbone, which allows them to swim faster and get away from predators. All fish in the ocean today share these common ancestors. -
Life still confined to the sea, seaweed is the only plant
About 600 million years ago seaweed was one of the first plants with more than one cell. During the Proterozoic period seaweed had to evolve to live in freezing temperatures and deep in the ocean where there's no sunlight for photosynthesis. -
First signs of land plants and animals
Researchers found that land plants first starting growing on earth about 700 million years ago and land fungi about 600 million years earlier. Prior to this study it was believed that the earth was covered with barren rocks and some bacteria.
The first animals on earth date back 600 millions years. Primitive metazo, is the name of the three groups of sponges, cnidarians (corals, sea anemones and jellyfishes) and worms. -
First insects and spiders
Insects date back 400 million years. We don't know much about them because everything we know about ancient life comes from fossils and insects don't have many hard bones to fossilize. Most evidence we have comes from insects preserved in tree sap. They occasionally get caught in the sap dripping from the trees. This sap hardens over time and the insect can stay there for millions of years. -
Amphibians dominant
Amphibians were once the most dominant animals on earth. It may be strange because now they are some of the smallest animals and don't look very dangerous, 300 million years ago some of them would reach up to 15 feet long which isn't massive now but was huge back then. They were so big they would terrorize smaller animals and were the apex predators of their ecosystem -
Mammal-like reptiles appear
Mammal like reptiles are aslo called Synapsids. Synapsids evolved from basal amniotes and are one of two groups of amniotes, the other group is sauropsids a group that includes modern day reptiles and birds. -
Dinosaurs abundant, first birds appear
Dinosaurs first appeared about 240 million years ago. They dominated the near-tropical earth during the Jurassic period. The Archaeopteryx was the first dinosaur like bird which first appeared about 150 million years ago, towards the end of the Jurassic period. There were also pterosaurs, they were flying reptiles and are the largest ever vertebrates to ever fly. -
Dinosaurs extinct, increase in diversity of mammals of all kinds
The diversity of mammals rapidly grew straight after dinosaurs went extinct. New analysis of fossil records show that placental mammals grew in the 10 million years after dinosaurs went extinct, this is because a lot of predators to mammals disappeared with the dinosaurs. Mammals clearly took advantage of this period and increased rapidly in population and size. -
Bibliography
("What Is Seaweed? - Plant History - Quatr.Us") "Curiocity". explorecuriocity.org. N.p., 2016. Web. 10 Nov. 2016. "Fossils Insects - 400 Million Years Of Evolution". museumvictoria.com.au. N.p., 2016. Web. 9 Nov. 2016. Strauss, Bob and Bob Strauss. "300 Million Years Ago, Giant Amphibians Ruled The Earth". About.com Education. N.p., 2016. Web. 9 Nov. 2016. "Jurassic Period - Zoomdinosaurs.Com". Enchantedlearning.com. N.p., 2016. Web. 9 Nov. 2016. -
Bibliography
"Mammal Diversity Exploded Immediately After Dinosaur Extinction". Ucl.ac.uk. N.p., 2016. Web. 10 Nov. 2016. "Anatomically Modern Human". En.wikipedia.org. N.p., 2016. Web. 10 Nov. 2016. Wethington, Nicholos and Nicholos Wethington. "How Did The Milky Way Form? - Universe Today". Universe Today. N.p., 2016. Web. 16 Nov. 2016. "The Habitable Planet Unit 1 - Many Planets, One Earth // Online Textbook". Learner.org. N.p., 2016. Web. 12 Nov. 2016. -
Bibliography
"Khan Academy". Khan Academy. N.p., 2016. Web. 16 Nov. 2016. "Synapsid". En.wikipedia.org. N.p., 2016. Web. 17 Nov. 2016. "Complex, Multicellular Life From Over Two Billion Years Ago Discovered". ScienceDaily. N.p., 2016. Web. 17 Nov. 2016. -
Anatomically modern humans appear
Anatomically modern humans evolved from archaic humans in the middle of the stone age about 200,00 years ago. The existence of anatomically modern humans marked the dawn of the subspecies to Homo sapiens, Homo sapiens sapiens which all humans alive today belong to. -
Bibliography
("BBC - GCSE Bitesize: The Big Bang Theory") "When Were The First Stars Born?". Canadian Space Agency website. N.p., 2016. Web. 9 Nov. 2016. Astronomy, Science. "First Galaxies Born Sooner After Big Bang Than Thought". Space.com. N.p., 2016. Web. 9 Nov. 2016. "Geologist Analyzes Earliest Shell-Covered Fossil Animals". The UCSB Current. N.p., 2016. Web. 9 Nov. 2016. "The 500 Million Year History Of Vertebrates". Bookbuilder.cast.org. N.p., 2016. Web. 9 Nov. 2016.
