Carbon dating age determination
Third, magnetism in rocks can be used to estimate the age of a fossil site.
This method uses the orientation of the Earth's magnetic field, which has changed through time, to determine ages for fossils and rocks.
However, the age of each fossil primate needs to be determined so that fossils of the same age found in different parts of the world and fossils of different ages can be compared.
There are three general approaches that allow scientists to date geological materials and answer the question: "How old is this fossil?
This is the principle of original horizontality: layers of strata are deposited horizontally or nearly horizontally (Figure 2).
Each time a new layer of sediment is deposited it is laid down horizontally on top of an older layer.
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.
Despite seeming like a relatively stable place, the Earth's surface has changed dramatically over the past 4.6 billion years.
Mountains have been built and eroded, continents and oceans have moved great distances, and the Earth has fluctuated from being extremely cold and almost completely covered with ice to being very warm and ice-free.