The Story of Earth Notes 5,000 Million Years Ago: A newborn star Dust and rocks surround the sun, no Earth has formed yet. 4,540 Million Years Ago: Gravity pulls the rocks and dust together to form Earth. Earth is 1200 degrees Celsius, with Carbon Dioxide, Nitrogen, and Water Vapor in the air A planet the size of Mars called Theia collides with Earth Gravity pulls the Earth back together and forms the moon. 3,900 Million Years Ago: Debris from the solar system bombards Earth. The meteorites contain small amounts of salt and water. The water accumulates on the solid ground forming oceans The moon is so close it is causing huge waves. 3,800 Million Years Ago: Tiny islands come up from the water. Volcanoes are erupting and the lava hardens to form land. The land gets bigger and eventually becomes our continents. More meteorites hit Earth, releasing minerals and amino acids. Water contains lots of chemicals that created microscopic bacteria. 3,500 Million Years Ago: Stromatalites evolve and can do photosynthesis, producing oxygen, filling the ocean with O2. Oxygen is transforming the atmosphere. 1,500 Million Years Ago: Oxygen levels rise The core pushes plates around 30 degrees Celsius and days are 18 hours long 750 Million Years Ago: Volcanoes release CO2, which combines with water to form acid rain The rain causes the temperature to drop to -50 degrees Celsius and the Earth freezes 650 Million Years Ago: A layer of ice 3 meters thick surrounds the Earth The ice reflects all of the sunlight and heat from the sun back into space. 620 Million Years Ago: Volcanoes break through the ice and release CO2, which causes the temperature to rise. As the ice melts, oxygen trapped in the ice is released. 600 Million Years Ago: Earth warms up Bacteria thrives in the oceans Days are 22 hours long. 540 Million Years Ago: Lots of life in the ocean Bacteria have evolved into prehistoric slugs. The first animals with backbones appear. Lots of worms, sponges, plants, and “sea monsters” in the ocean. 460 Million Years Ago: Ozone The sun has deadly radiation, so nothing is living on the land. Oxygen from our atmosphere and the radiation from the sun combine to create ozone. Ozone builds up and blocks the harmful radiation on Earth 375 Million Years Ago: Plants and Fish Plants are covering the land. Fish are rapidly evolving Tiktaalik: a fish with bones that make it capable of lifting itself out of the water, primitive lungs 360 Million Years Ago: Amphibians Animals are moving from the ocean to the land First amphibians Huge dragonflies, millipedes, spiders, and other insects 320 Million Years Ago: Reptiles First reptiles appear 300 Million Years Ago: Lots of plants and animals As they die, their remains are covered by lava and other sediment. This begins forming the coal and oil we use today. 250 Million Years Ago: Rise of early mammals and larger reptiles. The Earth erupts and ash, Carbon dioxide, and lava cover the land 90% of all life dies Minerals from the ash cause algae to thrive, causing the oceans to turn pink. Methane from the Earth is escaping and causing the temperatures to rise. 200 Million Years Ago: There is one landmass called Pangaea Temperature is stabilizing and plant life is returning Dinosaurs are thriving and they don’t have much competition. 190 Million Years Ago: Pangaea begins to break apart. Fish are filling the oceans. The dead fish layer the seafloor and are covered by sediment. The pressure from the rocks will create the oil that we use today. 180 Million Years Ago: The North American Plate is moving away from the European plate, 2 cm per year, forming the Atlantic Ocean. Animals from all over are populating the new ocean. The seafloor is pushing and pulling creating underwater mountains. 65 Million Years Ago: Dinosaurs are still thriving. An asteroid hits the Gulf of Mexico with the force of millions of nuclear bombs, destroying everything in its path. Many meteorites also hit the earth, causing earthquakes and tsunamis, The surface of the Earth reaches 275 degrees Celsius Most plants and animals die Mammals are able to survive by living underground and eating almost anything. 47 Million Years Ago: 24 degrees Celsius and days are 24 hours long. The planet is almost as we know it today. The atmosphere is much like our own. Ancestors of primates, Darwinius ida India is colliding with Asia, causing the land to buckle and creates the Himalayan Mountains. When snow from the mountain range melts, it forms many rivers in Asia. 20 Million Years Ago: Our planet is as we know it today. The land masses are mostly where they are today. 4 Million Years Ago: A rift opens up on the East coast of Africa, which forms a range of mountains. These mountains block rain from reaching the center of the continent and the Sahara Desert is formed. Our ancestors are forced to walk on two feet instead of four in search of food. 1.5 Million Years Ago: The earliest species of humans is on the planet. They walk on two feet and don’t drag their knuckles. 70 Thousand Years Ago: A species of humans cross the Red Sea, out of Africa. Their population increases and they spread to other parts of the world. 40 Thousand Years Ago: An ice wall is spreading and the temperature drops incredibly. The Earth enters an ice age. The ice sculpts the Earth, forming all sorts of land and water features. 20 Thousand Years Ago: The ice is causing the seas to shrink. A land bridge is formed between Siberia and the Americas. Humans travel over the bridge and start populating North America. 14 Thousand Years Ago: The ice begins to retreat to the Arctic’s and the Great Lakes are formed in the process. 6 Thousand Years Ago: The ice has fully retreated and is now completely in the Arctic’s. Present: Humans are fully evolved as we know them today and live in the world as we know it.