Precambrian time, also known as the beginning of time began 4.6 billion years ago and ended 544 million years ago. Its climate switched from hot and cold periods all throughout Precambrian time. The tilt on earth’s axis causes an unstable climate. There was not much land and tons of water at that time. The super continent stretches from the top of the earth to to the bottom of it. It is located mostly on the eastern hemisphere. Small bacteria were the first animal life on Earth. Soon after that multicellular organisms formed. The first 3 categories of animals are sponges, annelids(worm-like organisms), and cnidarians(jellyfish- like organisms). Plants started to produce oxygen in a process called photosynthesis. At the end of the time period, there was an around-world ice age and the super continent broke into big pieces. Oxygen levels rose due to the ozone layer. That is what happened during Precambrian Time.