Current understanding of the history of life is probably close to the truth because it is based on repeated and careful testing and consideration of data.The rejection of the validity of fossils and of dating by religious fundamentalists creates a problem for them: Fossil sequences were recognized and established in their broad outlines long before Charles Darwin had even thought of evolution.Fossils document the order of appearance of groups and they tell us about some of the amazing plants and animals that died out long ago.Fossils can also show us how major crises, such as mass extinctions, happened, and how life recovered after them.
The discovery of means for absolute dating in the early 1900s was a huge advance.I think it’s fair to say that any educated person over the age of 10 or so has probably heard of carbon dating.But I realized the other day that even as an adult with a fair amount of scientific knowledge, I could not articulate exactly how or why carbon dating works.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.
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.