The Paleontological Collections provide irreplaceable documentary evidence of Italy’s territorial heritage with findings of fundamental importance in recomposing the nation’s stratigraphic record. The four collections illustrate the organisms that filled the lands and seas over a time-span from the Paleozoic Era (approx. 570,000,000 years ago) until today. The 96,000 fossils of invertebrate and vertebrate animals include specimens of various taxonomic groups, such as Fish, Reptiles, Trilobites, Ammonites, Clypeasters, Graptolites, Rudists, and Echinoids. The approximately 3,000 fossils of large Cenozoic Mammals from Latium, Tuscany, and Sicily were essential in reconstructing continental environments of the Quaternary period.

The Plant Collections include around 600 finds from various sites in Italy, such as the flora from Monte Jano of the Carboniferous Epoch in Tuscany and Sardinia, plant fossils unearthed in the Roman countryside from the Quaternary Period, and findings of Pteridophytes and Spermatophytes from Paleozoic rock layers in Germany and Poland. The specimens on display in the Hall of Sciences were found mainly in Central Italy and in rural areas around Rome in particular.

As long as the Pleistocene lasted—from 2,580,000 to 11,700 years ago—as most of the Northern Hemisphere, Central Italy was affected by extreme climatic variations, with alternating cold glacial phases and mild interglacial phases that had a significant impact on territorial biodiversity, geomorphology, and hydrography, partly due also to volcanism and tectonics. Fauna typical of warm climates, such as elephants and hippopotami, alternated with cold climate species, such as mammoths and giant deer.

Long, mild interglacial phases permitted the wide distribution of large herbivores typical of temperate and humid environments, such as the floodplains in the Roman countryside formed by the Tiber and Aniene rivers in whose sediments these large mammals fell prey and fossilized for subsequent discovery. The main fossiliferous deposits are found in different parts of Rome and its suburbs, particularly in the lower Aniene Valley (Casal de’ Pazzi, Saccopastore, Sedia del Diavolo, Monte delle Gioie, Ponte Mammolo) and along the Roman road Via Aurelia (Polledrara, Malagrotta, Via Aurelia, Torre in Pietra, Castel di Guido). The results obtained from the study of these sites have enabled the reconstruction of the complex geological and climatic history of an area whose environmental conditions also favored the human settlement documented by the presence of stone-working sites and other anthropological findings. The most famous are the two Homo neanderthalensis skulls unearthed in 1929 and 1935 at Saccopastore Quarry on the eastern bank of the Aniene River, now part of Rome’s Nomentano neighborhood.