https://padlet.com/liquorls261/by4tn5c0wgrvrlwf en-us 2023-07-20 23:55:56 UTC 2023-07-21 04:13:17 UTC hello@padlet.com liquorls261 https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648834418 Earth formed about 4.6 billion years ago, and it ran with little to no atmosphere. It was a mix of very hot gasses and solids, and it had a surface made of entirely molten. Its circumstances are obviously not safe for humans today to live on, with hydrogen, sulfide, methane, and up to 200 times the amount of carbon dioxide then we have now. Luckily for us, the Earth's surface cooled and solidified later on, which allowed water to build up.]]> 2023-07-21 00:15:22 UTC https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648834418 liquorls261 https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648863671 Around 2.7 million years ago, bacteria began to appear on earth and flourish its oceans. Specifically, a bluish green microscopic organism called cyanobacteria was created. Cyanobacteria contributed greatly to helping make the Earth what it is today, by creating photosynthesis. As they gathered free oxygen from photosynthesis, 1% of today's 21% oxygen was formed.]]> 2023-07-21 00:58:33 UTC https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648863671 liquorls261 https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648905427 Stated earlier, cyanobacteria helped create photosynthesis and produce free oxygen. As time went on, these tiny organisms helped produce enough oxygen to react with the methane inside of the atmosphere. This cleared the methane haze up and changed the world forever, leaving the sky to turn blue.]]> 2023-07-21 01:53:12 UTC https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648905427 liquorls261 https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648933580 Between 700-550 million years ago, there was a significant increase of oxygen levels in the ocean and atmosphere. In-between these years, about one fifth of the 21% of oxygen was produced. This increase in oxygen favored the evolution of some organisms by providing them with energy, however, some other organisms were forced into extinction due to oxygen being extremely poisonous to them. Some scientists have said that the significant increase in oxygen helped contribute to the surge in sea life known as the Cambrian explosion around half a billion years ago. Trilobites and eurypterids began evolving around this time.]]> 2023-07-21 02:26:29 UTC https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648933580 liquorls261 https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648984584 Plants began to emerge at this time, and life again had a major effect on the Earth's atmosphere. Oxygen levels raised up to the near amount we currently have, about 20%. In-between this time period, forests grew on land and swamps filled low-lying areas. Usually when a plant or animal dies and starts to decay, microbes take care of it by decomposing it and combining oxygen with carbon to make carbon dioxide, producing a greenhouse gas. Thankfully, major amounts of dead plants were buried under swamps, out of contact with oxygen. This made the carbon dioxide levels drop significantly, and the Earth was much cooler than it was in its previous years.]]> 2023-07-21 03:46:10 UTC https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648984584 liquorls261 https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648997939 Over the past 290 million years, Earth has actually reached higher temperatures than it does today. Between 200 and 45 million years ago, polar ice caps were almost nonexistent, and winter was warmer around the globe. This was a safe environment for many plants and animals as they lived heavily in these regions. The warmest part out of all of these years was named the Eocene Epoch, with characteristics like the Arctic Ocean being barely frozen and palm trees growing very far up north.]]> 2023-07-21 04:13:17 UTC https://padlet.com/liquorls261/by4tn5c0wgrvrlwf/wish/2648997939