Summary. Palaeontology also means palaeobiology. Thus, the knowledge of the modern environment, including its biological community, represents the best tool to interpret the ancient environments and their fossils. More and more frequently, palaeontology needs other disciplines to obtain detailed and refined data of stratigraphy, ecology and climatology.

Stratigraphy concerns the study of the rocks in chronological order. Biostratigraphy is a classic tool to identify the arrangement of the sedimentary rocks. The identification of the fossil content provides a relative dating together with other data coming from analyses of geochemistry (isotopes), magnetostratigraphy, that can be modified into radiometric datings. Archaeology provides good examples of such applications of the palaeontology.

Ecology and palaeoecology represent the study of links between organisms/environments and fossils/ancient environments, respectively. Useful tools are numerous organisms that can fix well defined elements in their skeletal parts (shells, bones, etc.). Such skeletal parts can be found as fossils. Good examples are represented by small crustaceans (ostracods) that fix in their calcareous carapaces heavy metals, so indicating modern and ancient pollution.

Palaeontology also is helped by geochemistry that through isotopic analyses (delta C13) identifies continental-to-marine environments in stratigraphic successions.

Climatological and palaeoclimatological studies highlight several organisms that define cold-to-warm conditions. The present time faunal and floral distributions can easily verify such conditions. The fossils can demonstrate these conditions. However, palaeontology needs geochemistry that through isotopic analyses (O16/O18) evidences climatic changes in stratigraphic successions.

However, one of the most famous examples of integrated studies (palaeontology, geochemistry, magnetostratigraphy, sedimentology, etc.) is represented by the identification of the K/T boundary, i.e. the geological moment representing the mass extinction of 65 MY ago). This extinction produced famous victimes (dinosaurs, rudists, ammonites, etc.). It is also present in the Karst, at Padriciano and in Slovenia. Such event is testified by the disappearance and subsequent appearance of some fossils, but also by geochemical data (Ir anomaly, negative shift of delta C13) and magnetostratigraphy. Among these data, Ir anomaly also testifies the meteorite impacts occurred 65 MA ago (Yucatan, Mexico).