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Human evolutionary theory has a history rife with racial biases in what might be considered its distant past that can appear glaringly obvious from our current vantage point. Despite the recognition that as a social activity science is always vulnerable to such biases (and science that attempts to uncover human origin stories all the more so), commitment to the scientific method can lead us to believe that we have improved on, overcome, or otherwise escaped these tendencies in our contemporary practices, whether through scientific contrition, changing social context, or better training and composition of research teams or as a result of advances in technologies and methodologies. This article adapts the evolutionary biology concept of introgression, which refers to the hybridization and repeated bidirectional backcross exchange of information between species, as a metaphorical frame to examine science itself and to trace the ways in which historic race biases from earlier, disowned human evolution research have been retained and selected for beneath the surface of current genomic research today. It takes as its focus the sequencing of the Neanderthal genome, first announced in 2006 and refined since, and the explosion of scientific research comparing that sequence to present-day human DNA from individuals around the world to illustrate the ways in which current research questions and findings in comparative evolutionary genomics draw on and dredge up earlier biases, albeit adapted to and disguised within contemporary social relations and power differentials. [ABSTRACT FROM AUTHOR]

Recent fossil discoveries of early human ancestors from paleoanthropological sites in Africa and elsewhere have demonstrated how various phases of human evolutionary history were much more complicated than previously thought. The fossil record is always far from complete, and in some time slices too scarce, to provide a very detailed picture of how we became who we are today. Inadequate sample size and unsampled time periods in the fossil record are major impediments to conducting comprehensive and more rigorous analyses to test new and existing hypotheses. However, there are also instances where a single specimen, such as the 3.8-million-year-old Australopithecus anamensis cranium (MRD-VP-1/1) from the Afar region of Ethiopia, can provide a wealth of information on the paleobiology, paleoecology, paleogeography, and phylogenetic relationships of a particular species. Such specimens are extremely rare in the fossil record, but when they are discovered, they can fundamentally increase our understanding of the anatomy of a species and clarify its relationships with other species. For example, MRD-VP-1/1 provides the first glimpse of the craniofacial anatomy of Australopithecus anamensis and demonstrates that this species retained a number of primitive features similar to those of its predecessors, while sharing derived features with its descendant, Australopithecus afarensis. This is new information that paleoanthropologists did not have until the discovery of MRD-VP-1/1. The mosaic nature of its morphology combined with its geological age places Au. anamensis at the root of the origin of the genus Australopithecus and as a possible ancestor of all later hominins. Although this species has been hypothesized as the linear ancestor of Au. afarensis , recent fossil discoveries from Woranso-Mille indicate that MRD-VP-1/1 probably represents a geographically isolated Au. anamensis population that may have followed an evolutionary trajectory different from its conspecific populations elsewhere. The contemporaneous presence of mid-Pliocene non- Australopithecus afarensis species at Woranso-Mille and in the Turkana Basin (Kenya) shows just how complex the earlier phases of human evolution were. These assumptions will require further investigation with increased sample sizes and better understanding of temporal and spatial distribution of different hominin species during the mid-Pliocene of eastern Africa. [ABSTRACT FROM AUTHOR]

Beginning with a chapter on evolutionary theory and another on technology, including dating technologies, he moves in Chapter 3 to the main thrust of the book: human evolution. Ian Tattersall has been at the forefront of paleoanthropological work on human evolution for 40 years and this book provides a lucid, compelling, and brisk tour of the fruits of this work. Richard Wrangham has suggested that early hominids solved this problem by cooking food, making the nutrients more available (2009. [Extracted from the article]

With a long history predating modern humans, big-game hunting has been implicated in catalyzing human evolution through nutritional and provisioning benefits. An alternative view argues for this practice as a costly signaling strategy geared toward increasing male fitness through prestige and status benefits. We examine this possibility across contexts that include early human evolutionary phases, as well as historical and contemporary time periods. Our interpretive exploration across several disciplinary literatures covers hunting in the hominin evolutionary past, extant hunter-gatherers, and finally, political and cultural big-game hunting and sport as recounted in historical and mythological narratives. In some of these, we find strong support for costly signaling as a beneficial strategy. Further, in contexts where subsistence is not an articulated motivation for hunting, we argue that benefits accrued through male-to-male signaling and resulting status as measured through prestige and dominance could be a key component of social hierarchies and, ultimately, fitness outcomes. [ABSTRACT FROM AUTHOR]

Selection and transport of materials for tools is ubiquitous throughout our species' evolutionary history. Yet our understanding of early human material culture is heavily skewed toward lithic technology. This poses challenges when reconstructing our technical origins, as organic raw materials, especially plants, likely played a significant role despite their absence from the record until 300 kya. Studies of plant-tool use by living apes can serve as a proxy to reconstruct such aspects of human behavior. Employing archaeological methods, we investigated raw material procurement for termite-fishing tools by three chimpanzee (Pan troglodytes schweinfurthii) populations in Tanzania: Gombe, Issa, and Mahale. All communities exploited plant sources from the immediate vicinity of termite mounds, as well as farther away, and reused them. However, at Issa, more parts were sourced per plant, with the number of removals decreasing as distance from the mound increased. These disparities are likely caused by environmental differences. Issa apes might try to minimize transport costs in what is a comparably more open and drier habitat with fewer suitable sources available near mounds. Despite similar raw material types being available, Issa and Mahale chimpanzees exclusively used bark for tool manufacture, while at Gombe, various materials were employed; these differences may reflect cultural variants. Our study highlights how environmental and cultural factors shape chimpanzee technology and identifies similarities to raw material selection processes inferred for Oldowan tool users. The archaeology of the perishable, even if at its infancy, is providing a new framework for reconstructing archaeologically invisible aspects of early human behavior and our own technological origins. [ABSTRACT FROM AUTHOR]

Biological market theory has in recent years become an important part of the social evolutionist's toolkit. This article discusses the explanatory potential and pitfalls of biological market theory in the context of big picture accounts of the evolution of human cooperation and morality. I begin by assessing an influential account that presents biological market dynamics as a key driver of the evolution of fairness norms in humans. I argue that this account is problematic for theoretical, empirical, and conceptual reasons. After mapping the evidential and explanatory limits of biological market theory, I suggest that it can nevertheless fill a lacuna in an alternative account of hominin evolution. Trade on a biological marketplace can help explain why norm-based cooperation did not break down when our Late Pleistocene ancestors entered new, challenging social and economic environments. [ABSTRACT FROM AUTHOR]

Host immune tactics at the level of the single cell have a very large effect on disease progression and host survival. These cell-level defense mechanisms, known as cell-autonomous immunity, are among the most important determinants of human survival, yet are millions to billions of years old, inherited from our prokaryotic and single-celled ancestors. An understanding of how cell-autonomous immunity has evolved in primates is crucial to understanding the human evolutionary story, not only because multiple infectious agents thought to have strongly affected human genomic evolution are excellent manipulators of cell-autonomous immunity, but because these defenses are found in every cell in every physiological system. The ubiquity of cell-autonomous immunity highlights a biological reality not commonly addressed in human evolutionary studies—that pathogens can mediate the evolution of all body cells and, therefore, all body systems, affecting human evolution in a cell-type-specific fashion. Here we explore these very ancient tactics in light of evolutionarily important human pathogens and illustrate inter-primate differences in the potential of such defenses. Often considered an independent physiological system in human evolutionary biology, the immune system is ubiquitous, integrated into every other aspect of human physiology. It is, effectively, the entire organism. We argue, therefore, that immunity and pathogen-mediated natural selection are considerations in the examination of the evolution and function of any human physiological system or trait. [ABSTRACT FROM AUTHOR]

Domestication is one of the most interesting and challenging processes in human and animal evolution. The fundamental change in subsistence strategies from hunting and gathering to farming that took place for the first time in the Levant more than ten thousand years ago profoundly changed human culture and biology, and set the groundwork for population growth, migrations, the rise of civilizations, and wealth disparities (Bocquet-Appel 2011 ; Gignoux, Henn, and Mountain 2011 ; Kohler et al. 2017). [ABSTRACT FROM AUTHOR]

One of the defining features of human evolution is our demographic success. As of August 2019, the world's population exceeds 7.7 billion. The human capacity for population growth has profound effects on people's lives today, but it is also one of the remarkable stories of our evolutionary past. Although most research and public attention has centered on the past 200 years, when growth has increased exponentially, global population growth prior to that was not trifling. Before the industrial era, humans populated all of the world's environments with more than a billion people. Importantly, it was deep in the past when the biological and social underpinnings were established that allow humans to excel as reproducers and survivors. The evolutionary trends in fertility and survival that gave rise to human demographic success were fundamentally shaped by our ability to cooperate. This essay focuses on how the human dietary niche and life history presented novel opportunities for cooperation that tied younger and older generations together in ways that gave us our demographic edge. [ABSTRACT FROM AUTHOR]

Some of Darwin's views on descent with modification were developed alongside his adoption of a number of concepts inspired by the domain that we would now call science and technology. Focusing on the period from Darwin's circumnavigation journey to the publication of the Origin in 1859, this essay explores the rich manuscript and published documentation left by Darwin to trace in detail his exposure to contemporary technologies and notions of invention. It argues that the parallel Darwin established on several occasions between the history of life on earth and human inventions was more than a metaphor. According to Darwin's radical evolutionary perspective, life and invention—including his own theory explaining descent with modification—belonged to the same domain. It further argues that Darwin's technology of life approach allowed him to make room for a plurality of causes driving evolutionary change, while at the same time avoiding the question of the origin of life. This same approach helped him to mold his scientific persona, while marking his distance from a mixed population of naturalists that included materialists as well as exponents of speculative German natural philosophy, although these were all frequent sources of reflection during his most creative years. [ABSTRACT FROM AUTHOR]

Global exposures to air pollution and cigarette smoke are novel in human evolutionary history and are associated with at least 12 million premature deaths per year. We investigate the history of the human exposome for relationships between novel environmental toxins and genetic changes during human evolution in six phases. Phase I: With increased walking on savannas, early human ancestors inhaled crustal dust, fecal aerosols, and spores; carrion scavenging introduced new infectious pathogens. Phase II: Domestic fire exposed early Homo to novel toxins from smoke and cooking. Phases III and IV: Neolithic to preindustrial Homo sapiens incurred infectious pathogens from domestic animals and dense communities with limited sanitation. Phase V: Industrialization introduced novel toxins from fossil fuels, industrial chemicals, and tobacco at the same time infectious pathogens were diminishing. Thereby, pathogen-driven causes of mortality were replaced by chronic diseases driven by sterile inflammogens, exogenous and endogenous. Phase VI: Considers future health during global warming with increased air pollution and infections. We hypothesize that adaptation to some ancient toxins persists in genetic variations associated with inflammation and longevity. [ABSTRACT FROM AUTHOR]

Discussions about the evolution of human social cognition usually portray the social environment of early hominins as highly hierarchical and violent. In this evolutionary narrative, our propensity for violence was overcome in our lineage by an increase in our intellectual capacities. However, I will argue in this article that we are at least equally justified in believing that our early hominin ancestors were less aggressive and hierarchical than is suggested in these models. This view is consistent with the available comparative and palaeoanthropological evidence. I will show that this alternative model not only does not support long-held views of human origins, but also has important consequences for debates about the evolution of our capacity for normative guidance. 1 Introduction 2 Philosophical Motivation 3 The Puzzle of Hominin Evolution 4 The Mosaic Hypothesis 5 Evidence for the Model 6 Palaeoanthropological Support 7 Philosophical Consequences [ABSTRACT FROM AUTHOR]

The novice will gain an appreciation for an interplay between cooperation and cultural evolution, as well as a fresh perspective on the origins of inequality. What distinguishes Sterelny's account is his multiple, positive feedback loops approach and his ability to see the nuances of cooperation. Readers familiar with this topic will gain insights into the author's method of explaining via positive feedback loops, his challenge to traditional theories, and his conclusions drawn from subtle conceptual distinctions. [Extracted from the article]

An introduction is presented in which the editor discusses various reports within the issue on topics including archaeology, evolutionary anthropology, and ethnology.

The development of the ability to throw projectiles for distance, speed, and accuracy was a watershed event in human evolution. We hypothesize that throwing first arose in threat displays and during fighting and later was incorporated into hunting by members of the Homo lineage because nonhuman primates often throw projectiles during agonistic interactions and only rarely in attempts to subdue prey. Males, who threw more often than females in both combat and hunting, would have been under stronger selection than females to become proficient at the ability to throw, intercept, and dodge projectiles as throwing skills became critical to success in combat and hunting. Therefore, we predict that males, more than females, should display innate anatomical and behavioral traits associated with throwing. We use data from a variety of disciplines to discuss: the sex differences in throwing speed, distance, and accuracy; sex differences in the development of the throwing motion; inability of training or cultural influences to erase the sex differences in throwing; sex differences in the use of throwing in sports, combat, and hunting; and sex differences in anatomical traits associated with throwing that are partly responsible for male throwing superiority. These data contradict the view held by many commentators that socialization rather than innate sex differences in ability are primarily responsible for male throwing superiority. We suggest that throwing is a male adaptation. [ABSTRACT FROM AUTHOR]

Humans are the only species capable of powerful and accurate overhand throwing. However, the evolution of this ability remains underexplored. Here we draw on several lines of evidence—anatomical, archeological, cross-species comparisons, and ethnographic—to develop a scenario for the evolution of throwing. Throwing has deep roots in the primate lineage. Nonhuman primates throw projectiles during agonistic interactions but rarely to subdue prey. Thus, we argue that throwing first arose during agonistic interactions and was later incorporated into hunting by human ancestors. The fossil record indicates that anatomical adaptations for high-speed throwing in Homo first appeared about two million years ago. Once the effective use of projectile weapons became critical to success in combat and hunting, the importance of the ability to throw, intercept, and dodge projectiles would have resulted in stronger selection on males than females to become proficient at these skills because males throw projectiles more often than females in both combat and hunting. [ABSTRACT FROM AUTHOR]

Recent technological developments in scientific dating methods and their applications to a broad range of materials have transformed our ability to accurately date rock art. These novel breakthroughs in turn are challenging and, in some instances, dramatically changing our perceptions of the timing and the nature of the development of rock art and other forms of symbolic expression in various parts of the late Pleistocene world. Here we discuss the application of these methods to the dating of rock art in Southeast Asia, with key implications for understanding the pattern of recent human evolution and dispersal outside Africa. [ABSTRACT FROM AUTHOR]

For more than half a century, prehistorians have grappled with radiocarbon-based chronologies that are often contradictory and imprecise. Several key debates in the Paleolithic have their roots, at least partially, in basic issues of chronology. When did Neanderthals disappear? When did Homo sapiens disperse across Eurasia? How long was the overlap among several hominin groups? Without reliable time control, these questions are unanswerable, and unravelling the Paleolithic remains a distant and virtually unachievable goal. It is only recently that the extent of the problems with the application of radiocarbon dating near the limit of the method has become understood. Major challenges have arisen, ranging from inadvisable and poor selection of samples, on the one hand, to the analytical, chemical, and instrumental challenges of dating the low amounts of residual radiocarbon in these samples, on the other. Recent work has led to significant developments in the field. In this paper, we briefly review some of these developments, drawing on recent work undertaken at two sites, Bondi Cave (Georgia) and Kostenki 14 (Russia). By comparing new radiocarbon determinations against previous results, it is possible to begin to quantify quite how erroneous some of the previous chronometric models were. [ABSTRACT FROM AUTHOR]

A deeper understanding of the eastern Asian Late Pleistocene paleoanthropological record will contribute to some resolution of the modern human origins debate. Here, I review the current state of the Late Pleistocene behavioral record with a particular focus on the Korean and Japanese records. In addition to questioning the applicability of the three-stage (Lower/Middle/Upper) Paleolithic sequence in the region and advocating a two-stage model (Early/Late), I add a number of behaviors to the definition of the eastern Asian Late Paleolithic, traditionally defined based on the appearance of blade-tool technology. In particular, any definition of this cultural period for this region should include the appearance of tanged points, ground stone tools, trap-pit hunting, and importantly, watercraft. Tanged points and trap-pit hunting represent an expansion of the Late Paleolithic foragers' diet breadth and an increased effectiveness in hunting large game. As well, ground stone tools, which included ground axes used for felling trees and woodwork, probably contributed to the building of sturdy watercraft necessary to make oceanic voyages. Finally, I briefly discuss the arguments for and against the pre-50,000 ka occupation of eastern Asia by modern Homo sapiens with a focus on four specific sites that are proposed to support the pre-50 ka model: Huanglong Cave, Fuyan Cave, Luna Cave (all in China), and Callao (Philippines). [ABSTRACT FROM AUTHOR]

Archaeological discoveries suggest that human interest in odd objects emerged as early as the end of the Lower Paleolithic with Homo erectus , although it is still difficult to understand why early humans collected these objects. Several studies show that nonhuman primates are able to appreciate the physical characteristics of their tools, but their interest in the physical properties of nonutilitarian objects has, to our knowledge, never been tested. Here, objects of different brightness, color, and shape were proposed to five orangutans to test whether odd objects intrigue orangutans (Pongo pygmaeus) and whether they induce specific and noticeable behavior. This preliminary experiment shows that orangutans are responsive to the physical properties of nonutilitarian objects, particularly visually striking, bright, and colorful objects. Our experiment shows that these are the most manipulated pieces, regardless of their respective proportions. However, unlike (early) humans, orangutans did not show any tendency to preserve objects. [ABSTRACT FROM AUTHOR]

In this paper we present a reconceptualization of the social dimension of the human niche and the evolutionary process that brought it into existence. We agree with many other evolutionary approaches that a key aspect of the human niche is a social environment consisting primarily of cooperating and altruistic individuals, not a Hobbesian social environment of "war of all against all." However, in contrast to the conception of this social environment as consisting of individuals who, in Boyd and Richerson's words, "cooperate with large groups of unrelated individuals," we propose that it is more accurately described as consisting of cooperating individuals who currently are often nonkin but who, until relatively recently in human existence, were primarily, and in many cases almost exclusively, kin. In contrast to the conception of this social environment coming into existence by way of a process of selection within and between groups, we propose that it is the result of selection operating on traditions originated by ancestors and transmitted to their descendants. We use our fieldwork in three areas of the world (New Guinea, Ecuador, and Canada) to illustrate this process and how current social environments can be roughly placed on a continuum from traditional to nontraditional. [ABSTRACT FROM AUTHOR]

Evolutionary theory predicts rigorous competition in nature and selfish behavior is thus seen as its inevitable consequence. Evidence of altruistic and cooperative behavior therefore appears at odds with evolutionary theory. However, evolutionary psychology suggests that past environments may be different from the current environments that humans inhabit. Here it is hypothesized that competition in two past environments might have led to strategies that favored altruism and cooperation toward nonkin. First, the expansion of the human brain is seen as requiring long-term, quality parental investment to sustain it. Altruistic displays could well have signaled an ability and willingness to provide such parental investment in a potential mate and been favored as a result. Second, the development of extra-somatic weapons is seen as leading to competition within hominin groups becoming more costly as disputes would have become lethal. A cooperative strategy could have achieved greater net fitness if the benefits of reduced involvement in such lethal disputes exceeded the costs of cooperation. Genes associated with human altruism and cooperation toward nonkin could thus have increased in frequency and come to be expressed in modern human populations despite the environments in which they evolved no longer being fully evident in the modern world. [ABSTRACT FROM AUTHOR]

We propose that plant foods containing high quantities of starch were essential for the evolution of the human phenotype during the Pleistocene. Although previous studies have highlighted a stone tool-mediated shift from primarily plant-based to primarily meat-based diets as critical in the development of the brain and other human traits, we argue that digestible carbohydrates were also necessary to accommodate the increased metabolic demands of a growing brain. Furthermore, we acknowledge the adaptive role cooking played in improving the digestibility and palatability of key carbohydrates. We provide evidence that cooked starch, a source of preformed glucose, greatly increased energy availability to human tissues with high glucose demands, such as the brain, red blood cells, and the developing fetus. We also highlight the auxiliary role copy number variation in the salivary amylase genes may have played in increasing the importance of starch in human evolution following the origins of cooking. Salivary amylases are largely ineffective on raw crystalline starch, but cooking substantially increases both their energy-yielding potential and glycemia. Although uncertainties remain regarding the antiquity of cooking and the origins of salivary amylase gene copy number variation, the hypothesis we present makes a testable prediction that these events are correlated. [ABSTRACT FROM AUTHOR]

This article explores a scientific technology—mitochondrial analysis—that underlies contemporary technoscientific phenomena such as genetic ancestry tests, ethnic diversity projects, and national genome projects. The article focuses on the figure of "Mitochondrial Eve," the most recent common matrilineal ancestor of modern humans, who lived in Africa a few hundred thousand years ago. Introduced by Rebecca Cann, Mark Stoneking, and Allan Wilson in 1987, Mitochondrial Eve became the object of an intense scientific and cultural debate, appearing in numerous journal articles and on the cover of Newsweek magazine, as well as in media commentaries on gender roles and popular culture. Through a critical reading of the press coverage of the mitochondrial debate between 1987 and 2000, this article explores an evolving set of cultural emotions, including hope, celebration, suspicion, and anxiety that shaped the idea of human ancestry during the debate. The article argues that the introduction of "Y-chromosome Adam" in 1995 marked a key shift in these affective negotiations, as it engendered a strictly heteronormative and symbolically white dynamic that rendered safe the feminist and multicultural potential suggested in early commentaries. The article concludes by considering how the affective politics of the mitochondrial debate inform the affective politics of today's biotechnologies. [ABSTRACT FROM AUTHOR]

The article investigates the impact of human microevolution and biocultural implications of Atlantic slave trade by an analysis of the genetic structure of the Angolares of Sao Tome Island in the Gulf of Guinea.

The authors argue that differentiation of hominids from great apes cannot be based strictly on a 'Pan troglodytes' model. An examination of four features of chimpanzee society reveals that other nonhumans also engage in analogous behaviors, which is relevant for reconstructions of hominid behavioral evolution.

One specimen of Ardipithecus ramidus, ARA-VP-6/500, is the earliest and also among the most complete fossil hominids ever recovered. Although it took more than a decade to extract, prepare, and analyze (along with a number of other less-complete specimens), the thoroughness of its recovery and preparation has yielded surprising revelations about its environment as well as new knowledge about the divergence of our earliest human ancestors from the last common ancestor they shared with chimpanzees. Decades of groundbreaking discoveries in developmental biology have also transformed our understanding of the evolutionary process itself, especially the need to view the significance of adult anatomical structures holistically. Today, no such structure can be reasonably understood without direct reference to its likely mode of morphogenesis. The twenty-first-century convergence of these two special sources of information requires a radical revision of how our early hominid forebears set the stage for our own subsequent evolution. Although we usually attribute our complex social structure to our massive brain, current evidence suggests that the reverse might have been true almost as far back as the original emergence of our clade. [ABSTRACT FROM AUTHOR]

I address Elliott Sober's reconstruction of the confirmation of evolution and offer a seemingly minor but important correction. I then survey evolutionary thought in Darwin as well as both before and after Darwin to demonstrate my modified reconstruction. Finally, I explain how this correction reflects the richness of evolutionary thought. [ABSTRACT FROM AUTHOR]

There is a growing consensus in early hominin studies that savannas did not play a significant role in the emergence of human evolutionary processes. Early hominins have been reported to be associated with densely wooded environments and sometimes forest, thereby reducing the importance of a shift from closed to open ecosystems in shaping these processes. In the second half of the twentieth century, two versions of the savanna hypothesis emerged: one depicted savannas as grasslands, the other as seasonal mosaic environments. Research has shown that the former is no longer tenable, but an increasing amount of paleoecological information provides compelling support for the latter. Here a critical review of the available paleoecological evidence is presented, and it is concluded that the savanna hypothesis not only has not been falsified but its heuristics are stronger than ever before. [ABSTRACT FROM AUTHOR]

A century of research has led to the recognition of multiple levels of technological variability in the Levantine Middle Paleolithic (MP) that cannot be resolved through single-cause explanatory models. Recent ecological models argue for continual occupation of the region and competitive coexistence of Neanderthal and modern human populations. Current paleogenetic studies underline the feasibility of the latter scenario. The Levantine MP offers a perspective on the interface of historical circumstances and long-term evolutionary mechanisms that structured in-tandem trajectories of technological and behavioral changes as well as insights into the dynamics of nondirectional behavioral complexities in the archaeological record. [ABSTRACT FROM AUTHOR]

The 145th symposium of the Wenner-Gren Foundation took place June 1-8, 2012, in Häringe Slott near Stockholm, Sweden. The primary goal of the symposium was to reframe discussions of behavioral evolution among Neanderthals and early modern humans. We hoped to replace conventions of a single scale of evolutionary progress (in which the primary benchmark is "modern human behavior") with a more Darwinian framework that could allow for independent evolutionary trajectories in different areas. The 15 participants included archaeologists researching material culture and subsistence in Eurasia, Africa, and China; physical anthropologists; a demographer; a geneticist; modelers of cultural evolution; and a climatologist. Participants were asked to draw on evidence in their areas of expertise, focusing on evolutionary trends in both modal tendencies and levels of variation/diversity within various regions during the interval in which the Middle Stone Age and Middle Paleolithic developed, spread, and eventually disappeared. It was agreed that there is compelling evidence for very different trajectories of cultural evolution in different parts of the world but that we are not yet in a position to fully evaluate and understand the outcomes of the parallel cultural evolutionary pathways among modern Homo sapiens in Africa and Neanderthals in Europe. Answering questions this large in scope requires synthesis on a large geographic scale comparable to studies by climate scientists and biogeographers. Conventional approaches to collecting, reporting, and analyzing archaeological and skeletal data do not lend themselves to rigorous tests of alternative evolutionary models. At the same time, the intellectual tools needed to research these questions are well developed, and answers are within reach. [ABSTRACT FROM AUTHOR]