Documentation by Jeannet is, in contrast, much better in this respect. The Mayer-Eymar fossil collection is presently located in the Natural History Museum in Basel. Fossils allow us to trace the evolution from simple to more complex forms throughout Geologic History. 430 ma, mammals 210 ma, angiosperm 125 ma, and primates 60 ma. In some cases, the fossil record reveals a continuous evolutionary history of a lineage, as with the marine invertebrates.
Fossils serve as time markers.
The life-time of a species typically lasts from one hundred thousand to millions of years. A species, once extinct, can never arise again. In the last 700 millions years, and especially in the last 550 million years, various fossil groups have been identified as especially useful index fossils, that replace each other through the geologic record. Fossils are also good indicators of the environmental conditions in which the rock formed, especially the place and the position where the organism was fossilized. Fossils allow to reconstruct past water depth, temperature, salinity, and many other factors.