This is supposed to be hard-headed pragmatism." The main "result" of this system, however, is merely the widespread acceptance of evolution.
A significant development of recent years has been the fact that many evolutionary geologists are now also recognizing this problem.
They no longer ignore it or pass it off with a sarcastic denial, but admit that it is a real problem which deserves a serious answer. which starts from a chronology of index fossils, and imposes them on the rocks.
The use of "index fossils" to determine the geologic age of a formation, for example, is discussed in an interesting way in an important recent paper by J. Each taxon represents a definite time unit and so provides an accurate, even 'infallible' date.
If you doubt it, bring in a suite of good index fossils, and the specialist without asking where or in what order they were collected, will lay them out on the table in chronological order." That is, since evolution always proceeds in the same way all over the world at the same time, index fossils representing a given stage of evolution are assumed to constitute infallible indicators of the geologic age in which they are found.
The fossils, in turn, are arranged on the basis of their assumed evolutionary relationships.
Thus the main evidence for evolution is based on the assumption of evolution.
Scientists know exactly how long it will take for half the quantity of the element to change, and this state is known as its half-life.
After another half-life has passed, the element will have decayed to a quarter of its original amount.
Sometimes, scientists already know the age of the fossil because fossils of the same species have been found elsewhere and it has been possible to establish accurately from those when the dinosaur lived.