Fossils/Fossil record-
Fossils are evidence of organisms that lived in the past. They may be direct (i.e. bones, teeth, shells, pollen) or indirect (i.e. footprints, teeth marks, nests).
Through fossils we are able to discover the ancestry of present animals from extinct animals, we are also able to determine the time of a significant environmental change (e.g. ice age)
Fossils become trapped in sedimentary or volcanic rock, which produce layers of different fossils, showing different species from different time periods in each. Primitive fossils are found in older sediment. A new fossil type/rock layer marks a change in environment, creating new niches and selection pressures thus new species.
Fossil Record- The collection of fossils of all sorts that provides a record of extinct life.
Relative/Actual Dating-
Relative- Refers to a general time period, e.g. 0.5 1 million years ago.
These methods do not employ the use of isotopes to date fossils.
Thermoluminescence-......
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