A warm and humid paleoecological context for the Neanderthal mountain settlement at the Navalmaíllo rockshelter (Iberian Central System, Madrid)

Neanderthals have been claimed to have had a selective adaptation to rugged, wooded landscapes that would have partially compensate their high basal metabolic rate and locomotor energetic costs through reducing search time and increasing diet breadth. The archaeological site of the Navalmaíllo rockshelter (Pinilla del Valle, Madrid), located in a mountain environment in central Iberian Peninsula, has been interpreted as a repeated short-term occupation hunting camp by Neanderthal groups, mainly focused on primary access to large bovids and cervids. Navalmaíllo rockshelter has also furnished fish, toads, frogs, tortoises, lizards and snakes remains. This association of amphibians and reptiles suggests a much warmer climate (þ 2.8ºC) for layer F than at present, with similar temperatures during the summer but higher temperatures throughout the remaining months. Rainfall was slightly more abundant (þ180.6 mm) than today, with a more contrasted regime during the year, with rainier winters and drier summers. A two-month period of aridity is observed during summer, representing a similar duration to present-day climatic conditions. Reconstructed landscapes are mainly constituted by open areas with dry grassland and rocky or stony areas, evolving laterally to humid meadows, probably close to the aquatic and peri-aquatic areas, such as rivers or ponds with riverside vegetation. Woodland environments are lso well represented around the site, with medium scrublands to forest formations. Fish complete this reconstruction by documenting the presence of a pre-mountain well-developed river system characterized by relatively cold, permanent, oxygen-rich, and running waters. Such reconstruction is in disagreement with previous pollen interpretation for Layer F that suggested a very open and cold environment. Our new interpretation suggests that the Neanderthal occupation of the Navalmaíllo rockshelter occurred during a somewhat temperate and humid period, probably within the later part of the Marine Isotope Stage 5, effectively favouring the presence of a high biodiversity around the site.C.S.-B. was supported by a FPI Predoctoral Scholarship (PRE 2020-094482) associated to the project CEX 2019-000945-M-20-1 with the financial sponsorship of the Spanish Ministry of Science and Innovation. A.F. was beneficiary of a post-doctoral grant APOSTD/2021/110, granted by the Generalitat Valenciana and co-financed by the Fondo Social Europeo (FSE). AMM was supported by the Agencia de Gestio d’Ajuts Universitaris i de Recerca (AGAUR) and the Departament d’Empresa i Coneixement de la Generalitat de Catalunya (grant 2021FI_B200207). “L'FSE inverteix en el teu futur”. A.C.D.-G. was beneficiary of a postdoctoral grant (POP-UCM CT17/17-CT18/17) funded by the Complutense University of Madrid. This research was conducted as part of competitive projects PGC 2018-094125-B-100 (MCIU/AEI/FED-ER,UE), PGC 2018-093925-B-C32 (MICINN-FEDER), 2017SGR1040 IPHES-URV and 2017SGR859 IPHES (AGAUR), PGC 2018-093612-B- 100 and PID 2021-122533NB-I00 (Ministerio de Ciencia e Innovacion y Agencia Estatal de Investigacion), and funded by the I þ D activities program for research groups run by the Education Secretariat of the Madrid Regional Government (H2019/HUM-5840). The study was also partly funded by the MAR, Grupo Mahou and Canal de Isabel II-Gestion. The Institut Catal a de Paleoecologia Humana i Evolucio Social (IPHES-CERCA) has received financial support from the Spanish Ministry of Science and Innovation through the “María de Maeztu” program for Units of Excellence (CEX 2019-000945-M).With funding from the Spanish government through the "Severo Ochoa Center of Excellence" accreditation CEX 2019-000945-M.Peer reviewe