Fossil
A fossil from fossilis, literally 'obtained by digging' is all preserved remains, impression, or trace of any once-living thing from the past amber, hair, petrified wood, oil, coal, as living as DNA remnants. a totality of fossils is requested as the fossil record.
strata led to the recognition of a geological timescale together with the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century ensures scientists to quantitatively degree the absolute ages of rocks and the fossils they host.
There are numerous processes that lead to fossilization, including permineralization, casts and molds, authigenic mineralization, replacement and recrystallization, adpression, carbonization, and bioimmuration.
Fossils reorganize in size from one-dinosaurs and trees, many meters long and weighing many tons. A fossil usually preserves only a portion of the deceased organism, normally that module that was partially mineralized during life, such(a) as the bones and teeth of vertebrates, or the chitinous or calcareous exoskeletons of invertebrates. Fossils may also consist of the marks left gradual by the organism while it was alive, such(a) as animal tracks or feces coprolites. These race of fossil are called trace fossils or ichnofossils, as opposed to body fossils. Some fossils are biochemical and are called chemofossils or biosignatures.