Question: My class and I went on a recent trip and we learned a lot about fossils what is the oldest fossil I the world ?

Maria McNamara answered on 12 Nov 2019:

Well, the oldest putative fossils are from the Nuvuaggituk Supracrustal Belt in eastern Canada. They are tiny microscopic tubular fossils preserved in 3D in silica that are 4.28 billion years old, and have been interpreted as the oldest fossil microbial filaments – indeed the oldest fossils – in the world. However they are really controversial because the dating puts them as older than the Great Heavy Bombardment. This was a period of Earth history from about 4.1-3.9 billion years ago where the Earth experienced a really intense period of meteorite activity, heating up the crust so much that any primordial oceans would have evaporated, most likely killing any life present. Some palaeontologists don’t believe that the NSB structures have been dated accurately. We just have to wait and see what future analyses show.