https://padlet.com/crumptat26/jna6xl9xb2q2bykk en-us 2023-04-25 23:12:57 UTC 2025-12-21 20:58:28 UTC hello@padlet.com crumptat26 https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895202 Earth's early atmosphere was primarily made up of gases emitted during the planet's formation 4.6 billion years ago. These gases included hydrogen, helium, methane, ammonia, and water vapor. Hydrogen, helium, methane, ammonia, and water vapor were among these gases. By releasing chemicals like carbon dioxide, nitrogen, and sulfur dioxide into the atmosphere, volcanic activity also contributed to its state. ]]> 2023-04-25 23:16:53 UTC https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895202 crumptat26 https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895287 During this time, Earth's crust cooled and the first continents formed. The atmosphere was primarily composed of methane, and no oxygen gas was present. Simple living cells emerged in the oceans, which did not require oxygen to survive. Cyanobacteria, which used photosynthesis to produce oxygen, emerged around 2.7 billion years ago and gradually increased the amount of oxygen in the atmosphere.]]> 2023-04-25 23:16:58 UTC https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895287 crumptat26 https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895423 Cyanobacteria appeared and multiplied, using photosynthesis to produce oxygen. Over several hundred million years, oxygen gradually accumulated in the atmosphere, changing it into the 21% oxygen condition it is in today. This event was a major turning point in Earth's history, allowing for the evolution of multicellular life.]]> 2023-04-25 23:17:07 UTC https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895423 crumptat26 https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895442 The Age of Oxygen refers to a period when oxygen levels in the atmosphere rose significantly due to the emergence and proliferation of photosynthetic organisms, most notably trees, causing oxygen levels in the atmosphere to rise dramatically. During the Carboniferous Period, oxygen levels in the atmosphere rose to as high as 35%, resulting in a cooler climate and the growth of extensive forests and wetlands. This period, known as the Age of Oxygen, is considered one of the most significant events in Earth's history, along with the emergence of oxygen on Earth, as it paved the way for the evolution of complex multicellular life forms.]]> 2023-04-25 23:17:10 UTC https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895442 crumptat26 https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895531 Earth has been largely warm throughout the last 290 million years, with changes in the atmosphere having an impact on the climate. Oxygen levels increased enough for animal life to exist. Polar regions were home to a wide variety of plants and animals between 200 and 45 million years ago, when the polar ice sheets were either minor or nonexistent. The Eocene Epoch, which lasted 65 million years ago, was the warmest period of that time, resulting in the emergence of palm trees as far north as Canada and dawn redwood forests that covered Ellesmere Island near the North Pole. The climate and environment at this time played a role in creating the Earth we live on today.]]> 2023-04-25 23:17:13 UTC https://padlet.com/crumptat26/jna6xl9xb2q2bykk/wish/2567895531