Neanderthals in changing environments from MIS 5 to early MIS 4 in northern Central Europe – Integrating archaeological, (chrono)stratigraphic and paleoenvironmental evidence at the site of Lichtenberg

Highlights

• Integrative multidisciplinary approach of geo-biosciences and archaeology.

• Precise chronology connects Neanderthal occupation to distinct climatic phases.

• Neanderthals adapted to changing and also severely cold environments in northern Central Europe.

• Variability of tool size, raw material and tool use in response to climate changes.

• First numerical dates for early Weichselian interstadials in the type area.

Abstract

The resilience of Neanderthals towards changing climatic and environmental conditions, and especially towards severely cold climates in northern regions of central Europe, is still under debate. One way to address this is to investigate multi-layered occupation in different climatic intervals, using independently-compiled paleoenvironmental and chronological data. Unfortunately, most open-air sites on the northern European Plain lack a robust chronostratigraphy beyond the radiocarbon dating range, thereby often hampering direct links between human occupation and climate. Here we present the results of integrative research at the Middle Paleolithic open-air site of Lichtenberg, Northern Germany, comprising archaeology, luminescence dating, sedimentology, micromorphology, as well as pollen and phytolith analyses. Our findings clearly show Neanderthal presence in temperate, forested environments during the Mid-Eemian Interglacial, MIS 5e and the latest Brörup Interstadial, MIS 5c/GI 22 (Lichtenberg II). For the previously known occupation Lichtenberg I, we revise the chronology from the former early MIS 3 (57 ± 6 ka) to early MIS 4/GS 19 (71.3 ± 7.3 ka), with dominant cold steppe/tundra vegetation. The early MIS 4 occupation suggests that Neanderthals could adjust well to severely cold environments and implies recurring population in the region between MIS 5 and MIS 3. The artefact assemblages differ between the temperate and cold environment occupations regarding size, blank production, typology and tool use. We argue that this distinctness can partially be explained by different site functions and occupation duration, as well as the availability of large and high-quality flint raw material. Raw material availability is in turn governed by changing vegetation cover that hindered or fostered sediment redeposition as a provider of flint from the primary source of the glacial sediments nearby.

Introduction

The “stereotype” Neanderthal is mostly perceived as a human species that lived in the cold and harsh climatic environments of the past glacial periods in Eurasia. But were Neanderthals indeed adapted to cold environments? This question has been a matter of debate in prehistory, biology and physical anthropology for a long time (e.g., Aiello and Wheeler, 2003; Churchill, 2008; Rae et al., 2011; Skrzypek et al., 2011; White and Pettitt, 2011). One way of addressing this open question is to analyze Neanderthal occupation at the northern extreme of their habitat, more precisely the northern part of Central Europe.

Currently, numerous sites suggest that Neanderthals settled in northern Central Europe during the Eemian Interglacial and during the first half of the last glacial cycle (Gaudzinski-Windheuser and Roebroeks, 2014; Hein et al., 2020; Litt and Weber, 1988; Nielsen et al., 2017; Richter, 2016; Thieme and Veil, 1985; Toepfer, 1958; Weber, 1990). However, the chronology of most late Middle Paleolithic sites is either poor and/or controversial (Jöris, 2004; Mania, 2002; Pastoors, 2001, 2009; Veil et al., 1994), and many of them are not dated at all. The majority of those sites are classified as late Middle Paleolithic by typological means only (Kegler and Fries, 2018; Richter, 2016). Due to this lack of precise site chronologies, even though we know that Neanderthals occupied the northern regions, we lack evidence of whether they stayed there only during warmer periods of the last interglacial - glacial cycle or if they also persisted through cold stadial conditions. So far, the only indication for the latter is the site of Salzgitter-Lebenstedt, Lower Saxony/Germany (Tode, 1982). At this site, the finds originate from layers containing cold climatic vegetation remains (Pastoors, 2001; Pfaffenberg, 1991; Selle, 1991), and are associated with glacial fauna. The presence of cranial and post-cranial Neanderthal remains (Hublin, 1984), clearly link Neanderthals to the accumulation of archaeological and faunal remains at the site. They hunted reindeer and manufactured bone tools from mammoth ribs (Gaudzinski, 1998, 1999). However, the dating of the site still lacks resolution. Uncertain ages at the upper limit of the ¹⁴C time scale, together with contrasting stratigraphic interpretation, place the site either in the Marine Isotope Stage (MIS) 5a/4 (Jöris, 2004) or MIS 4/3 transition (Pastoors, 2001, 2009). Furthermore, the integrity of the lithic assemblage is unclear, as the artefacts were found in several geological layers (Pastoors, 2001). Evidence for occupation during warmer early last glacial interstadials only comes from two sites of the northern Central European Plain so far. The first site is Neumark-Nord 2/0 (Laurat and Brühl, 2006), Saxony-Anhalt/Germany dating to either MIS 5c or 5a (Richter and Krbetschek, 2014; Strahl et al., 2010). The second site is Königsaue (Mania and Toepfer, 1973), Saxony-Anhalt/Germany. Neanderthal occupation is here associated with peat layers at a paleo-lakeshore, dating most probably to MIS 5a (Jöris, 2004; Mania, 2002; Mania and Toepfer, 1973; but see Hedges et al., 1998 for a potential MIS 3 age of the site). However, with the scarce evidence outlined above, it is currently not possible to reconstruct the timing of human presence in northern Central Europe, as well as behavioral response to short-term climatic shifts.

To address these issues, we need to contextualize the northern Neanderthal occupations using detailed paleoenvironmental reconstructions, derived from the same chronostratigraphic frameworks as the archaeological material, preferably with a temporal resolution on the millennial scale of Greenland Interstadials (Rasmussen et al., 2014). Since the Middle Paleolithic period is mostly outside the radiocarbon range, this kind of precision is usually reserved for loess regions, where highly-resolved sediment-paleosol sequences occur (Locht et al., 2016). Beyond the loess belt, at the northern margin of the Neanderthal habitat and the European Plain, occupation is conceived to have been most particularly affected by climatic fluctuations (Depaepe et al., 2015; Hublin and Roebroeks, 2009; Roebroeks et al., 2011). Across these landscapes, however, shallow sediment deposits in unison with frequent cryoturbation features often hamper the establishment of such a precise chronostratigraphic framework (Hein et al., 2020; Wiśniewski et al., 2019). Instead, the dating resolution commonly does not exceed the much coarser scale of Marine Isotope Stages (Lisiecki and Raymo, 2005a).

Here we present new results of our recent research at the late Middle Paleolithic open-air site complex of Lichtenberg, Lower Saxony/Germany (Veil et al., 1994), which was initially discovered in 1987 and excavated until 1993 by the Niedersächsisches Landesmuseum, Hannover, Germany. Lichtenberg represents a Neanderthal site at the potential northern limit of their geographic range (Nielsen et al., 2017). The site yielded one of the most prominent late Middle Paleolithic assemblages of the northern Central European Plain, as well as a sediment sequence encompassing deposits from MIS 5e through MIS 3 (Veil et al., 1994). Neanderthal occupations at Lichtenberg were associated with a paleo-lakeshore (Hein et al., 2021). Therefore, the long-lasting highly resolved sediment sequence composed of intercalated organic and clastic sediments is an ideal location to study climatic and environmental shifts, and to investigate the Neanderthal population dynamics at the northern limit of their habitat.

Our multidisciplinary investigations combine archaeological investigations with detailed sedimentological, chronological and paleoenvironmental studies of the find-bearing and associated non-find bearing layers of the sequence. Our research focusses on the following aims: (1) Can we connect Neanderthal occupations of northern Central Europe to a chronological resolution of Greenland Interstadial-Stadial level and thus to changing climatic conditions? (2) Did Neanderthals inhabit specific environments only, or did they adapt to different environmental conditions? (3) To which extent do archaeological assemblages vary in different environments and climates? And, most importantly, (4) did Neanderthals live in northern Central Europe only during warmer, forested phases of the last glacial, or could they also cope with cold climatic conditions and open landscapes in the stadials of the Early Weichselian and the Pleniglacial?