Fossils

• Fossils are the remains of organisms for millions of years ago, which are found in rocks
• Fossils may be formed

  • from parts of organisms that have not decayed because on or more of the conditions needed for decay are absent
  • when parts of an organism are replaced by minerals was they decay
  • as preserved traces of organisms, such as footprints, burrows and rootlet reaces
• Many early forms of life were soft-bodied, which means they have left few traces behind.