Carrying capacity and meat availability for the Neanderthal groups in the upper valley of the Lozoya River (Madrid, Spain): a key region for the study of their ecosystems in Central Iberia

Archaeological and Anthropological Sciences (2025) 17:84 https://doi.org/10.1007/s12520-025-02195-6 RESEARCH Carrying capacity and meat availability for the Neanderthal groups in the upper valley of the Lozoya River (Madrid, Spain): a key region for the study of their ecosystems in Central Iberia Lucía Molino1 · Guillermo Rodríguez‑Gómez1,2 · Theodoros Karampaglidis3,4 · Beatriz Trejo1,2 · Jesús A. Martín‑González5 · Enrique Baquedano6,7 · Juan Luis Arsuaga1,2 Received: 20 October 2024 / Accepted: 19 February 2025 / Published online: 21 March 2025 © The Author(s) 2025 Abstract Located in the upper valley of the Lozoya River, Cueva del Camino (Madrid, Spain) is one of the richest Early Pleistocene paleontological sites in the Iberian Peninsula. The results of the work carried out over the last three decades have led to the interpretation of the site as a hyena den with intermittent human presence. The faunal assemblage of layer 05 of Cueva del Camino dates to about 90 ka (MIS 5c) and includes small, medium, and large mammals. The presence of lithic industry and Neanderthal remains provide valuable insights into the strategies of past human groups in their access to animal resources. This study aims to determine the ecological conditions and availability of meat resources in the large mammal paleocommunity of Cueva del Camino by estimating carrying capacity (CC) and meat availability (TAB) in the upper valley of the Lozoya River. The estimates show a predominance of species with extreme body masses (either very small or very large) for CC, while TAB is mostly concentrated in small species. To evaluate and contextualize these estimates, the results were compared with other Pleistocene paleoecosystems of the Iberian Peninsula and with modern ecosystems. The upper valley of the Lozoya River reflects similar conditions to some Pleistocene faunal assemblages in Sierra de Atapuerca, such as Gran Dolina and Galería, and to the Serengeti National Park in the case of modern ecosystems. Based on density estimates and population size, the upper valley of the Lozoya River closely resembles populations of contemporary hunter-gatherer groups, and its conditions may have been sufficient to support a Neanderthal group of approximately 34 individuals. Keywords Cueva del Camino · Pinilla del Valle · Late Pleistocene · Large mammals · Paleoecosystems · Human ecology Introduction Resource availability is an important factor concerning the survival and distribution of species. In the case of human populations, it is widely known that meat resources have played a pivotal role for a significant part of our evolutionary * Guillermo Rodríguez‑Gómez 1 2 3 Departamento de Geodinámica, Estratigrafía y Paleontología, Universidad Complutense de Madrid, C/ José Antonio Novais 12, Madrid 28040, Spain Centro UCM-ISCIII de Evolución y Comportamiento Humanos, Avd/ Monforte de Lemos, 5, Pabellón 14, Madrid 28029, Spain Departamento de Ingeniería Geológica y Minera, Universidad de Castilla-La Mancha, Av. de Carlos III 21, Toledo 45004, Spain history, especially for European Pleistocene lineages (Speth 1987; Roebroeks 2001; Hublin and Richards 2009; Ferraro et al. 2013). It is stated that meat resources constituted an important part of the Neanderthal diet (Richards et al. 2000; Bocherens et al. 2005; Hublin and Richards 2009; Richards and Trinkaus 2009; Churchill 2014; Smith 2015; Rendu 4 Department of Archaeology, Hebrew University of Jerusalem, Jerusalem 9190501, Israel 5 Departamento de Matemáticas y Computación, Universidad de Burgos, Plaza Misael Bañuelos S/N, Burgos 09001, Spain 6 Museo Arqueológico y Paleontológico de La Comunidad de Madrid, Plaza de Las Bernardas S/N, Alcalá de Henares, 28801 Madrid, Spain 7 Institute of Evolution in Africa, Calle de Covarrubias 36, Madrid 28010, Spain Vol.:(0123456789) 84 Page 2 of 22 et al. 2019; Marín-Arroyo and Sanz-Royo 2022). However, many studies show that they had a diverse diet and consumed large amounts of plant resources (Stringer et al. 2008; Cortés-Sánchez et al. 2011; El Zaatari et al. 2011; Henry et al. 2011, 2014; Hardy et al. 2012; Sistiaga et al. 2014; Estalrrich et al. 2017; Power et al. 2018; Fiorenza et al. 2020; Zilhao et al., 2020; Salazar-García et al. 2021). Assuming that large mammals were a food source for Pleistocene human groups, their abilities to obtain these would be conditioned by ecological traits, abundance of prey and competition with other large carnivores (Bermúdez de Castro, 1995; Fariña, 1996; Palmqvist et al. 2003; Vizcaíno et al. 2004, 2010; Raia et al 2007; Meloro and Clauss 2012; Rodríguez-Gómez et al. 2013, 2014a, 2017c, 2024a). Delving deeper into the ecological frameworks in which human groups developed is a useful way to provide more insight into their subsistence strategies and the exploitation of resources. This is considered as key in the study of the evolution of human behavior (e.g., Kahlke and Gaudzinski 2005; Stringer et al. 2008). For this reason, it is essential to emphasize the importance of the following concepts: carrying capacity (CC) and meat availability (TAB, total available biomass). These are two indexes of great utility when characterizing ecosystems and paleoecosystems (e.g., Schaller 1972; Coe et al. 1976; OwenSmith 1988; Hayward et al. 2007; Rodríguez-Gómez et al. 2013, 2014a, 2024a, b; Hatton et al. 2015; Rodríguez et al. 2014; Domingo et al. 2017a, b, among others). The concept of CC is widely used in life sciences and has been applied to a wide range of analysis levels varying from molecular to ecological studies (see Sayre 2008). In present ecosystems, CC has been used to study the conditions of ecological populations of large mammals and how they manage to preserve their populations (Schaller 1972; Owen-Smith 1988; Hayward et al. 2007). This study uses the third meaning of carrying capacity defined by Sayre (2008) as the "intrinsic limit of a population increase in organisms” (Sayre 2008, p. 120). When applied to paleoecological studies, it is useful to determine the trophic networks between predators and preys by obtaining accurate biomass estimations (Palmqvist et al. 2003; Barnosky 2008; Sayre 2008; Rodríguez et al., 2014; Rodríguez and Mateos, 2018; Kindler et al. 2020; Rodríguez-Gómez et al. 2022a, 2024a, b). In this study, CC is used as a synonym for the biomass of prey species that an ecosystem can sustain continuously, as proposed by Coe et al. (1976), i.e., without considering the carnivore biomass, in order to analyze the relationship between predator and prey biomass (see Rodríguez-Gómez et al. 2024a). It also should be taken into account that the concept of carrying capacity is often used as a synonym for meat resources available in ecosystems (e.g., Vidal-Cordasco et al. 2022, 2023). However, several studies support the use of the concept of available meat as the biomass that comes from ecosystems and that could be used sustainably by secondary consumers, Ar (...truncated)