WHAT’S IN A NEANDERTHAL: A COMPARATIVE ANALYSIS Taylorlyn Stephan Oberlin College Dept. of Anthropology Advised by Prof. Amy Margaris TABLE OF CONTENTS I. Abstract – pg. 3 II. Introduction – pg. 3-4 III. Historical Background – pg. 4-5 a. Fig. 1 – pg. 5 IV. Methods – pg. 5-8 a. Figs. 2 and 3 – pg. 6 V. Genomic Definitions – pg. 8-9 VI. Site Introduction – pg. 9-10 a. Fig 4 – pg. 10 VII. El Sidron – pg. 10-14 a. Table – pg. 10-12 b. Figs. 5-7 – pg. 12 c. Figs. 8 and 9 – pg. 13 VIII. Mezmaiskaya – pg. 14-18 a. Table – pg. 14-16 b. Figs. 10 and 11 – pg. 16 IX. Shanidar – pg. 18-22 a. Table – pg. 19-20 b. Figs. 12 and 13 – pg.21 X. Vindija – pg. 22-28 a. Table – pg. 23-25 b. Fig. 14 – pg. 25 c. Figs. 15-18 – pg. 26 XI. The Neanderthal Genome Project – pg. 28-32 a. Table – pg. 29 b. Fig. 19 – pg. 29 c. Figs. 20 and 21 – pg. 30 XII. Discussion – pg. 32- 36 XIII. Conclusion – pg. 36-38 XIV. Bibliography – pg. 38-42 2 ABSTRACT In this analysis, I seek to understand how three separate lines of evidence – skeletal morphology, archaeology, and genomics – are used separately and in tandem to produce taxonomic classifications in Neanderthal and paleoanthropological research more generally. To do so, I have selected four sites as case studies: El Sidrón Cave, Mezmaiskaya Cave, Shanidar Cave, and Vindija Cave. El Sidrón, Mezmaiskaya, and Vindija all have detailed archaeological records and have yielded Neanderthal DNA. Shanidar is one of the oldest and most well-documented Neanderthal sites. Alongside the four sites listed above, the findings of the full-coverage Neanderthal genome will be used as a “site” of sorts to understand how genetics can inform and supplement morphological and archaeological data. Ultimately, the data presented here is more useful to contextualize the meta- interactions between paleoanthropological subdivisions rather than to answer, “what is a Neanderthal?”. INTRODUCTION In order to explore the limits of Neanderthal morphology, behavior, and genetics, we must first acknowledge traditional definitions of Neanderthals. The Smithsonian Institution defines them as “members of Homo neanderthalensis; our closest extinct human relative”. The European Nucleotide Archive, which hosts all of the genome sequences derived from Neanderthals, classifies the organism of origin as Homo sapiens neanderthalensis. But among anthropologists, the reigning definition of Neanderthals tends to omit a taxonomic name in favor of labeling them as: “Late Pleistocene human populations living in Europe and parts of Western Asia until approximately 30,000 years ago…this hominid group was morphologically different from its contemporaries and from later human populations”.30 Traditional morphology guidelines paint Neanderthals as short and squat people, possessing large and wide noses, thick and pronounced brow ridges, and sometimes even brains larger than modern humans.6, 24, 26, 28, 34 Despite these common descriptive approximations of Neanderthal morphology, there is no consensus in paleoanthropology regarding what exactly defines a Neanderthal. No current numerical standards decisively defining the limits of Neanderthal morphology yet exist, and it is even difficult to find clearly photographed Neanderthal skeletal and cultural remains. In recent years, our understanding of Neanderthal behavior has changed rapidly. Historically, Neanderthals were associated with the Mousterian lithic (stone tool) industry and were believed to deliberately bury their dead.3, 40, 70, 71, 73, 82 Recent evidence shows that they produced art and jewelry.48, 81 But irrefutable evidence of language and more sophisticated tool building currently remain elusive All citations in this document will follow the format dictated by the journal Science. The only differences are that journal 3 titles are not abbreviated and the bibliography is in alphabetical order. Science published the draft sequence of the Neanderthal genome and since then has published many significant findings on Neanderthal culture and biology. for most extinct hominins classified as Neanderthals; capabilities that have sometimes been used to define all modern humans excluding their Neanderthal contemporaries. But as I will discuss, archaeological evidence is often used to support a previous species designation rather than explicitly define one in the way that morphological and anatomical data are used. The latest form of evidence in paleoanthropology, ancient DNA, promises to objectively find the genetic basis of human evolutionary history and link anatomical observations. Yet, as we will see, genomic data only complicate and contradict previous morphological and archaeological-based classification of Neanderthals. Additionally, paleogenomics is also subject to computational and statistical biases, comparable to the consequences of solely using morphological and behavioral landmarks. In this analysis, I seek to understand how three separate lines of evidence – skeletal morphology, archaeology, and genomics – are used separately and in tandem to produce taxonomic classifications in Neanderthal and paleoanthropological research more generally. To do so, I have selected four sites as case studies: El Sidrón Cave, Mezmaiskaya Cave, Shanidar Cave, and Vindija Cave. El Sidrón, Mezmaiskaya, and Vindija all have detailed archaeological records and have yielded Neanderthal DNA. Shanidar is one of the oldest and most well-documented Neanderthal sites. Alongside the four sites listed above, the findings of the full-coverage Neanderthal genome will be used as a “site” of sorts to understand how genetics can inform and supplement morphological and archaeological data. Ultimately, the data presented here is more useful to contextualize the meta- interactions between paleoanthropological subdivisions rather than to answer, “what is a Neanderthal?”. HISTORICAL BACKGROUND Neanderthal bones were the first set of fossilized hominins to ever be found and identified as belonging to an ancient extinct human lineage. The Neanderthal type fossil was uncovered in 1856 by German miners in Neander Valley. Among the fragments were: a skull case, femurs, arm bones, ribs, and scapulae.76 Type fossils are the original remnants of a species uncovered and are used as the standard for all other species identifications. In retrospect, scholars realized that fossils from Belgium and Gibraltar (1829) were also Neanderthals rather than long-dead arthritic humans.76 To date, Neanderthal remains have been exclusively found in Europe and Asia unlike their contemporaries, anatomically modern Homo sapiens (AMH), of which are found across the world. To explain this unequal population distribution, two models have emerged: the regional continuity and replacement models. Put forth by the physical anthropologist Wolpoff, the regional continuity model states that 4 later members of Homo evolved from independently from regional hominin groups.14, 30 This model supports clinal variation and genetic drift seen in smaller populations. The replacement model, championed by paleontologists including Stringer and Andrews, is less popular than the regional continuity hypothesis. The latter suggests that all modern Homo sapiens are descended from archaic Homo sapiens that recently migrated out of Africa; overtaking Neanderthal and other Homo populations residing in Eurasia.11, 74 Further complicating ideas about Neanderthal evolutionary origins are paleoanthropologists (like Harvati et al) who believe that Neanderthals are an exception to the regional continuity model based on their extreme morphology.11, 29 Fig. 1: Neanderthal geographic distribution Credit: Open Access METHODS To address the questions posed in the abstract, I will utilize morphological landmarks, archaeology, and genomics in this analysis. The following methodology can be used as a guideline to explain how I will interpret the published data. Morphological Landmarks Skeletal morphology is used to ascertain phenotypes and variation within a population. Biological anthropologists use morphology to set species limits based on accepted parameters of variation. To best understand how changes in skeletal form influence hominin species definitions, 5 cranial landmarks of interest based on qualitative and quantitative analyses will used to explore the limits of Neanderthal species classifications. There are eight general categories of craniofacial landmarks used to evaluate Neanderthal morphology.28 The first is the shape and orientation of the infra-orbital region – which is typically classified as “inflated” in Neanderthal specimens. Second is the degree of antero-inferior glabella projection relative to the brow ridge and is used in differentiating pre- and early Neanderthals. Third, the position and sagittal orientation of the face is used; generally relatively forward. A strong juxtamastoid eminence is expected, which results in the crest of the digastric fossa border. Occipital plane convexity, or occipital “bunning” is a fifth classical Neanderthal trait. Reduced mastoid processes, high mid-facial prognathism, and large piriform (nasal) apertures are the final groups of Neanderthal skeletal classifications.28 Despite these categories, morphological-based speciation presents a number of difficulties. Landmark descriptions are subject to human bias, fossil availability and preservation conditions, what kind of tools and measurement system was utilized, and small sample sizes. There is no way to circumvent these constraints, so in this study, all data obtained from morphological analyses