This would make the world about 5,650 years old in Ussher's day and about 6,000 years old now.Although Ussher also based his calculations on a painstaking analysis of many other literary sources as well as the Bible, his was not a scientific investigation.A fossil can be studied to determine what kind of organism it represents, how the organism lived, and how it was preserved.However, by itself a fossil has little meaning unless it is placed within some context.
By comparing fossils of different primate species, scientists can examine how features changed and how primates evolved through time.
Geologists divide this age into major and minor units of time that describe the kinds of geological processes and life forms that existed in them.
Earth's geologic record was formed by constant change, just like those that occur routinely today.
By combining multiple geochronological (and biostratigraphic) indicators the precision of the recovered age can be improved.
Geochronology is different in application from biostratigraphy, which is the science of assigning sedimentary rocks to a known geological period via describing, cataloguing and comparing fossil floral and faunal assemblages.