Fox dietary ecology as a tracer of human impact on Pleistocene ecosystems

Abstract

Nowadays, opportunistic small predators, such as foxes (Vulpes vulpes and Vulpes lagopus), are well known to be very adaptable to human modified ecosystems. However, the timing of the start of this phenomenon in terms of human impact on ecosystems and of the implications for foxes has hardly been studied. We hypothesize that foxes can be used as an indicator of past human impact on ecosystems, as a reflection of population densities and consequently to track back the influence of humans on the Pleistocene environment. To test this hypothesis, we used stable isotope analysis (δ 13 C, δ 15 N) of bone collagen extracted from faunal remains from several archaeological sites located in the Swabian Jura (southwest Germany) and covering a time range over three important cultural periods, namely the Middle Palaeolithic (older than 42,000 years ago) attributed to Neanderthals, and the early Upper Palaeolithic periods Aurignacian and Gravettian (42,000 to 30,000 years ago) attributed to modern humans. We then ran Bayesian statistic systems (SIBER, mixSIAR) to reconstruct the trophic niches and diets of Pleistocene foxes. We observed that during the Middle Palaeolithic period, when Neanderthals sparsely populated the Swabian Jura, the niches occupied by foxes suggest a natural trophic behavior. In contrast, during the early Upper Palaeolithic periods, a new trophic fox niche appeared, characterized by a restricted diet on reindeer. This trophic niche could be due to the consumption of human subsidies related to a higher human population density and the resulting higher impact on the Pleistocene environment by modern humans compared to Neanderthals. Furthermore, our study suggests that, a synanthropic commensal behavior of foxes started already in the Aurignacian, around 42,000 years ago.

A refined proposal for the origin of dogs: the case study of Gnirshöhle, a Magdalenian cave site

“…Furthermore, a retreat into glacial refugia would not necessarily require a shift in the trophic niche of the focal species, and hence under the refugium hypothesis, we would predict a diet composition similar to that of pre-LGM canids from southwestern Germany. Results of dietary reconstructions from the pre-LGM periods of the Swabian Jura 17 have shown that all studied canids belonged exclusively to one group with high δ 15 N values that primarily fed on megafauna. While we observed the same pattern in the Magdalenian 'wolf ' niche (niche A), canids from Gnirshöhle behaved differently, which led us to reject the refugium hypothesis.…”

Linking Human Perceptions and Spotted Hyena Behavior in Urban Areas of Ethiopia

“…Further, increased urbanization may facilitate the loss of connectivity between people and nature [4], which has clear consequences on potential human-carnivore interactions. While humans have shaped carnivore behavior since the Middle Paleolithic [5], recent global examples abound of a rapidly emerging scenario where large carnivores coexist with humans in densely populated urban settings and humans likely have strong effects on carnivore behavior [6]. This realignment of human-carnivore urban interactions is occurring across six continents, including coyotes (Canis latrans) in North America [3], leopards (Panthera pardus) in India [7], brown bears (Ursus arctos) in Eastern Europe [8], jaguarondi (Puma yagouaroundi) in South America [9], and spotted hyenas (Crocuta crocuta) in Africa [10].…”

Earliest evidence for hunter-gatherer impacts on raven diet and ecology in the Gravettian of Southern Moravia

“…Isotope data on dietary relationships and overlaps between red foxes -another privileged group of early adopter animals -and Upper Palaeolithic humans in Southwest Germany between ca. 40,000 and 30,000 years ago 29 has shown that synanthropism has deeper historical roots than previously assumed, emerging under favorable conditions already in hunter-gatherer contexts of the Late Pleistocene. The data on common ravenfeeding behavior during the mid-Upper Palaeolithic Pavlovian presented in this paper adds to this growing body of evidence on behavioral change in animals catalyzed by low-threshold ecosystem impacts of small-scale hunter-gatherer societies, providing the currently earliest example of raven synanthropism in human evolution.…”