Fossils
- Created by: sxdewinder`
- Created on: 09-05-15 11:37
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- Fossils
- Formed from Gradual Replacement by minerals
- 1)Things like teeth, shells, bones etc, which don't decay easily, can last a long time when buried
- 2)They're eventually replaced by minerals as they decay, forming a rock like substance
- 3)The surrounding sediments also turn to rock, but the fossil stays distinct inside the rock and eventually someone digs it up
- Formed from Casts and Impressions
- 1)Sometimes fossils are formed when an organism is buried in a soft material like clay
- 2)The clay hardens around it and the organism decays, leaving a cast of itself
- 3)Things like footprints can be pressed into these materials when soft, leaving an impression when it hardens
- Formed from Preservations in places where no decay happens
- 1)In amber and tar pits there's no oxygen or moisture so decay microbes can't survive
- 2)In glaciers its too cold for the decay microbes too work
- 3)Peat bogs are too acidic for decay microbes
- No one knows how life began
- There are various hypotheses suggesting how life came into being
- These hypotheses can't be supported or disapproved because there's a lack of valid and reliable evidence
- Formed from Gradual Replacement by minerals
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