Camp dels Ninots
Location: Caldes de Malavella (la Selva, Girona)
Cronology: Upper Pliocene
Director: J. Agustí, G. Campeny and B. Gómez
Camp dels Ninots is located in the western part of the town of Caldes de Malavella (Girona). Its name is due to silicifications, in particular opal (SiO2nH2O) since its growth generates several rounded shapes called menilites, popularly known as "ninots" (puppets).
The Camp dels Ninots site is a phreatomagmatic volcanic eruption of Pliocene age (3.1 Ma) which subsequently formed a lake. Such volcanic structures are called "maar". The specific geological conditions, corresponding to lake sedimentation, make it ideal for the preservation of fossils. The appearance of complete skeletons mostly in anatomical connection leads us to consider the site, according to the German term, a fossil-Lagerstätte.
The set of recovered fossils and plant and animal remains provides direct data concerning to the biological environment and climate of the northeast of the Iberian Peninsula during the Upper Pliocene and allows to compare them to climate changes produced in Europe in the last 3 million years.
The lake formed inside the volcano offered optimal conditions for the establishment of ecological dynamics. The animals which died around it were submerged by the water and their bodies were deposited at the bottom of the lake. The characteristics of these waters, sometimes mineral saturated, created the optimal conditions for an excellent conservation of the skeletons that we have discovered.
The faunal remains consist in macrovertebrates, turtles, amphibians, fish and rodents. The macrovertebrates are represented by tapirs (Tapirus arvernensis), bovines (Alephis tigneresi) and rhinoceros (Stephanorhinus jeanvireti). Turtles are represented by the species Mauremys leprosa and Chelydropsis cf. pontica. The fossil assemblage is completed with amphibians like the sharp-ribbed salamander (Pleurodeles cf. sp.), webbed newts (Lissotriton aff. helveticus) and green frogs (cf. Pelophylax perezi), freshwater fish of the group of cyprinids (Leuciscus sp. Luciobarbus sp.) and isolated remains from the rodent Apodemus atavus. All this fauna allows us to study and explain how the environment was and which were the relationships established between these different animal species.
The coexistence of Stephanorhinus jeanvireti and Alephis tigneresi, and the paleomagnetic data obtained from all the stratigraphic sequences of the maar, give us a normal polarity (Gauss) for all the sequence with two inverse changes (Kaena and Mammoth), with a sedimentation rate that takes place in 200 ka, situating the fossil layers in 3.1 Ma, near the MN15-MN16 transition.
The flora is abundant and is composed by vegetal macroremains such as leaves imprints, fruits and trunks in the lacustrine clays and pollen remains captured in the sediment. These data correspond to a subtropical climate and landscape, plenty of laurisilva (laurel forest).
In conclusion, systematic fieldworks at the Camp dels Ninots site are revealing a real treasure for international palaeontology and palaeobotany. The large quantity, variability and well-preservation of the recovered assemblage properly make it a fossil-Lagerstätte. Its exceptionality does not only offer a unique opportunity to study an ecosystem from the Pliocene, but it provides paleoenvironmental data to help us understand climate change dynamics developed until today.