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.
He has written some 30 books on dinosaurs and paleobiology, ranging from professional tomes to popular kids’ books. Learn the facts in Evolution 101, browse the resource library, read about evolution in the news, or discover a wealth of materials to help educate others about evolution and related concepts—it’s all right here!
online directory of dinosaur exhibits fro around the world. t=sub_pages&cat=8 Many natural history museums and universities worldwide offer public participation programs in dinosaur events, such as fossil hunting or fossil cataloguing. The list is too long to mention here, so a couple of examples are provided to get you going on your search for programs in your area: Explore U. fossil collecting locations that are detailed on this site.
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.
Results from different techniques, often measured in rival labs, continually confirm each other.
Every few years, new geologic time scales are published, providing the latest dates for major time lines.New discoveries have filled in the gaps, and shown us in unimaginable detail the shape of the great ‘tree of life’.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.A key point is that it is no longer necessary simply to accept one chemical determination of a rock’s age.Age estimates can be cross-tested by using different isotope pairs.These demonstrate that, of course, we do not know everything (and clearly never will), but we know enough.