Fossils are usually first revealed by the process of erosion, or by quarrying. They are found in sedimentary rocks which have been formed from mud and sand laid down millions of years ago. The remains of animals and plants are buried in the layers of rock. These sedimentary rocks are often buried deep beneath layers of other rocks that do not contain fossils. They are often exposed in sea cliffs, where the rock is worn away by the waves. Mining and quarrying also expose the deeper layers of rock, and many fossils are found in the loose material at the foot of rock faces.
Where are most dinosaurs discovered?
Most fossils have been found in Europe and North America, but they have also been found in most other parts of the world. In recent years, huge numbers of new and exciting fossils have been discovered in China, including huge new sauropods and several of the small dinosaurs which seem to have given rise to modern birds.
Fossils of mammals are not so old as those of the dinosaurs, and they are found in other regions. In particular, fossils of early man and the ancestors of mankind have been found in Africa.
Could we ever reconstruct an extinct animal?
We know that it is very unlikely that a dinosaur can be brought to life because its DNA is no longer complete. However, there are other possible ways of re-creating more recent animals.
Woolly mammoths are often found buried in the permanently frozen ground of Siberia and Alaska, and attempts have been made to extract DNA from the carcasses. It is hoped that this material could be inserted into the egg cells of a modern elephant, so a mammoth could be born again.
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