This Canidae is important because it signals the so-called “wolf-event”, the faunal turnover marked by the massive expansion of diffusion areas or migrations of wolf-like dogs as a consequence to the climate changes of the Quaternary, characterised by the oscillation of the temperatures and the progressive growth of the aridity (2.5-2.4 million years ago circa). This entails the arrival in Europe of the representatives of the genus Canis: Canis etruscus is, in fact, the oldest species. It had a similar size to that of the modern wolf, it is likely that it was a social animal and therefore hunted in packs. Among the favourite prey of the canids were the "fake" deer of Nesti and the bush-antlered deer.

In the ecosystem of the Early Pleistocene of the Upper Valdarno, it is one of the most impressing predators. It belongs to the genus Homoterium and is part of the subfamily of the most famous genus Smilodon. It had a “sloped” appearance, like that of a hyena, because its forelimbs were longer than its hindquarters. The skull was robust and equipped with strong and quite long canines. Of this animal are known various species, among those, is the European crenatidens.

The Etruscan bear was a widespread Ursidae in Europe in the Early Pleistocene, once believed to be at the origin of the European and American Brown bears. The specimens of the begging of Pleistocene were small, similar to an Asian black bear, that could weight around 200 kilos. On the contrary, these specimens, that lived at the end of Pleistocene, could reach the dimension of a contemporary Brown bear. It was an opportunistic species, that colonized a great variety of habitats even though it was more suited to woodland environments. Its diet was omnivorous and it included a vast range of plants and animals, including fishes. This bear became extinct at the end of the Early Pleistocene when it was replaced by the ancestors of the modern Brown bear arriving from Asia.

The Auvergne Bear was a common species of bear in Europe and China during the entire Pliocene, with several subspecies. It was a small Ursidae typical to forest areas, similar to the existing Asian black bear especially in terms of teeth, even though they were smaller. The Auvergne Bear was the first representative of the genus Ursus, the direct ancestor of the Black bear, the Brown bear and the Cave bear in Europe and North America. In Europe, it gives rise at the end of Pliocene (2.6 million years ago circa) to the Etruscan bear.

This big hippopotamus is a late representative of the fauna of the upper Villafranchian age, in the Upper Valdarno (2-1.5 million years ago circa), when the landscape was characterized by forests and savannas, following the drying up and the lowering of the temperatures at the beginning of the Pleistocene (2.6 million years ago circa). Like modern hippos, it was a big herbivore and semiaquatic, the males had particularly long canines used as a defence mechanism but also to combat for territory. Is possible that this species of hippopotamus lived until circa 126,000 years ago, the beginning of the Late Pleistocene, even though the last fossils of this specie date back to circa 500,000 years ago.

This big animal is one of the five species of extinct Proboscidae that we can find in the Upper Valdarno. It belongs to the Elephantidae family, it comes from Africa and is a distant relative of the famous woolly mammoth. It was a big animal, some subspecies could reach a shoulder height of about 4 meters and an estimated weight of 11 tonnes, comparable to the African bush elephant, the largest living terrestrial animal. The molars of this animal show the changes of the climate in Valdarno, from a hot and humid climate, with a landscape mainly characterised by forests, to a more arid climate, characterised by open spaces. Mammuthus meridionalis was a herbivore with a varying diet and fed on leaves, the bark of trees and short plants and grass, differently from the older Proboscidea like the Auvergne mastodon and the Borson mastodon.

The Late Pliocene Rhino was a relatively slender animal, of a medium-large size compared to the coeval rhinos. This rhinoceros lived with other animals such as the Auvergne tapir, the Auvergne mastodon and the Borson mastodon. The low dental crown typical of a herbivore, suited to a diet of leaves, roots and bark, is a testimony to the hot and humid climate.

The Urus was the ancestor of domestic cattle: probably originated in India between 2 and 1.8 million years ago, at the beginning of the second half the Early Pleistocene, meanwhile, the first known remains in Europe date back to the beginning of Middle Pleistocene (800,000 years ago circa). It stood out from domestic cattle mainly for its size and the shape of its horns: it could reach a shoulder height of about 1.80 meters, the horns were robust and shaped like a lyre, straight with the point curved upwards, and very long. In winter the Urus gathered in big herds, meanwhile, in summer the herds were made up of female and small calves, the males lived in separate herds or alone. They lived primarily in the open spaces of swampy environments and humid forests.

The steppe bison represents the climate changes during the Pleistocene, that lead to cooling and drying of the environment and culminates in the so-called Ice Ages. This animal, found in the Upper Valdarno from the end of the Middle Pleistocene, originated in South Asia around the half of the Early Pleistocene. Similar to modern bison, with a shoulder height of about 2 meters and an estimated weight between 700 and 800 kilos, with horns as long as half a meter. The presence of thick hair, compared to modern bison, indicates an animal adapted to colder climates. Moreover, it fed predominantly on herbage in a steppe-like environment. This animal went extinct, like many other animals of that glacial period, at the end of Pleistocene in Europe and Asia and slightly later in North America, being replaced by the current species of bovids.

This Equidae is part of the animals of the so-called "Third Phase" of the Valdarno, that occurred at the end of the Middle Pleistocene and the beginning of the Late Pleistocene (between 300,000 and 100,000 years ago circa), where we see a progressive cooling and drying of the environment, with the creation of wide-open spaces of steppe and the arrival of animals that demonstrate this changes. This animal probably originated in North America at the beginning of the Calabrian (1.8 million years ago circa), and then emigrated to the Far East going through The Bering Strait.