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Older dates may change by a few million years up and down, but younger dates are stable.
For example, it has been known since the 1960s that the famous Cretaceous-Tertiary boundary, the line marking the end of the dinosaurs, was 65 million years old.
Repeated, and tough, regimes of testing have confirmed the broad accuracy of the fossils and their dating, so we can read the history of life from the rocks with confidence. Educators have permission to reprint articles for classroom use; other users, please contact [email protected] reprint permission. Currently, he is studying certain basal dinosaurs from the Late Triassic and the quality of different segments of the fossil record.
He holds the Chair in Vertebrate Paleontology at the University of Bristol, UK, in addition to chairing the Masters program in paleobiology at the university.
These demonstrate that, of course, we do not know everything (and clearly never will), but we know enough.
Darwin and his contemporaries could never have imagined the improvements in resolution of stratigraphy that have come since 1859, nor guessed what fossils were to be found in the southern continents, nor predicted the huge increase in the number of amateur and professional paleontologists worldwide.
All these labors have not led to a single unexpected finding such as a human fossil from the time of the dinosaurs, or a Jurassic dinosaur in the same rocks as Silurian trilobites.
Paleontologists now apply sophisticated mathematical techniques to assess the relative quality of particular fossil successions, as well as the entire fossil record.
Early geologists, in the 1700s and 1800s, noticed how fossils seemed to occur in sequences: certain assemblages of fossils were always found below other assemblages. Since 1859, paleontologists, or fossil experts, have searched the world for fossils.
In the past 150 years they have not found any fossils that Darwin would not have expected.