PaleoAnthropology

Book Review of Diet, Activity, and Social Practice. Addressing Everyday Life in Human Skeletal Remains

Kyle Pontieri — Tue, 24 Oct 2023 00:00:00 +0200

Book review.

Obituary: In Memory of William Howard Kimbel (1954–2022)

Shara Bailey, Amy Rector — Tue, 24 Oct 2023 00:00:00 +0200

Dr. William ("Bill") H. Kimbel passed away on April 17, 2022. Bill was a much-admired and internationally renowned scholar of paleoanthropology, best known for his field work in Hadar, Ethiopia. His contributions to understanding the origin, evolution, and anatomy of Australopithecus afarensis and early Homo shaped how paleoanthropologists interpet the fossil record. With his regular work in the Ethiopia National Museum and Hadar, Bill also supported the community of students, scholars, and colleagues in Ethiopia. Through his research, public outreach, and student training, Bill’s scientific rigor has been a benchmark against which all paleoanthropological work is measured. He was a beloved colleague, mentor and friend who is deeply missed.

Obituary of Sally McBrearty (1949-2023)

Christian A. Tryon — Tue, 24 Oct 2023 00:00:00 +0200

Obituary.

Introduction to the Special Issue

Robert Acio Benitez, John Murray, Susan Antón — Tue, 24 Oct 2023 00:00:00 +0200

This is the first part of a special issue on niche construction, plasticity, and inclusive inheritance in the context of the extended evolutionary synthesis. In this part there are seven contributions:

Benitez, R.A., Murray, J.K., Anton, S.C.: Introduction to the special issue: niche construction, plasticity, and inclusive inheritance: rethinking human origins with the extended evolutionary synthesis, part 1
Lala, K.N., O’Brien, M.J.: The cultural contribution to evolvability
Smail, I.E.: Community niches and evolution of generalist primates: a preliminary assessment of Plio-Pleistocene Cercopithecidae
Stock, J.T., Will, M., Wells, J.C.K.: The extended evolutionary synthesis and distributed adaptation in the genus Homo: phenotypic plasticity and behavioral adaptability
Sterelny, K.: Niche construction, cumulative culture, and the social transmission of expertise
Goodrum, M.R.: Reconceiving paleoanthropology in the era of the modern evolutionary synthesis
Tattersall, I.: Let sleeping syntheses lie

The Cultural Contribution to Evolvability

Kevin Lala, Michael J. O'Brien — Mon, 17 Oct 2022 00:00:00 +0200

Abstract. Evolvability is an emerging and synthetic topic that is making an impact in a variety of evolutionary fields. Although several definitions of evolvability have earned currency, most share a focus on the capacity or potential of systems to evolve. The suggestion that this capacity depends in part on the complexity of the focal organism’s development, and hence that different organisms evolve in fundamentally different ways, is a key point of contention in debates over the importance of evolutionary developmental biology and the merits of an extended evolutionary synthesis. Here we sketch the important contributions that human and nonhuman cultural processes make to the capacity to evolve and suggest that the cultural contribution to evolvability is key to understanding human and hominin evolution.

Keywords: adaptation, culture, evolvability, extended synthesis, learning, niche construction

Community Niches and Evolution of Generalist Primates: A Preliminary Assessment of Plio-Pleistocene Cercopithecidae in Africa

Irene Smail — Mon, 17 Oct 2022 00:00:00 +0200

Niche construction theory has increasingly received attention in paleoanthropology as a new focus for considering the evolutionary consequences of hominin tool-use and cultural adaptation starting in the Pleistocene. Modern humans excel at dramatic landscape modification, allowing us to regulate the effects of natural selection on our own species while simultaneously imposing novel selective forces on other living organisms. The long-standing effects of this current and past niche construction by our species makes it challenging to explore the timing and effects of hominin behavioral adaptations using modern analogues alone. In this paper I employ a community ecological approach to address evolutionary trends within a group of generalist primates—the Cercopithecidae—from Pliocene and early Pleistocene localities in Ethiopia, Kenya, and South Africa. Principal component analysis is used to model the dental ecomorphological niches of fossil cercopithecid species and taxocenes (a closely related subset of the faunal community), along with a comparative sample of extant cercopithecids from sub-Saharan Africa. Differences in the dental morphological niches of modern cercopithecid taxocenes can be attributed to variation in habitat conditions. Taxocenes appear more similar at local scales and co-occurring cercopithecids are relatively evenly dispersed in their dental morphological niche space, suggesting that they are able to maximize their available niches while avoiding competition within these taxocenes. Fossil taxocenes in eastern Africa (Hadar, Shungura, and Koobi Fora formations) also tend to occupy similar niches to one another and exhibit minimal spatial or temporal variation in their dental morphological niches. These eastern African taxocenes are distinct from those in South Africa (Makapansgat, Sterkfontein, Swartkrans, and Kromdraai), both in their overall niche positions and in measures of dispersion. Despite high species richness, cercopithecid taxocenes in the early Pleistocene of South Africa occupied restricted niches with more closely packed species, a pattern with no modern African analogue. The loss of this South African niche and an overall niche shift between early Pleistocene and modern cercopithecid taxocenes in Africa likely reflects a combination of climatic and habitat factors along with increasing impacts from tool-using hominins during the later Pleistocene. These results provide an important comparative pattern for considering how Pliocene hominins may have responded to environmental and habitat variation. Further, given the challenges of interpreting hominin behavioral evolution during this period, community paleoecological approaches like the one taken here can be useful for identifying changes in other mammalian groups in response an expanded hominin niche.

The Extended Evolutionary Synthesis and Distributed Adaptation in the Genus Homo: Phenotypic Plasticity and Behavioral Adaptability

Jay Stock, Manuel Will, Jonathan C.K. Wells — Mon, 17 Oct 2022 00:00:00 +0200

The extended evolutionary synthesis (EES) emphasizes integrative approaches to understanding distributed adaptability, incorporating development and intergenerational effects, inclusive inheritance and niche construction. We have previously argued that components of the EES, including enhanced phenotypic plasticity, life-history variation, social learning, behavioural flexibility, and niche construction, are characteristics of the hominin lineage that accommodated both environmental variation and the colonization of new environments (Wells and Stock, 2007). Over the past decade we have gained considerable resolution in our understanding of spatio-temporal variation in fossil hominin phenotypic variation, material culture, and behaviour, and a refined understanding of the intergenerational and developmental mechanisms driving phenotypic diversity within our species. This paper reviews evidence for phenotypic and behavioural diversity within the genus Homo to evaluate the hypothesis that our evolution is characterized by a shifting distribution of adaptability across different adaptive systems described by the EES, which we broadly group as physiology and development and cultural evolution. Adaptation that is distributed towards physiological and cultural mechanisms allows for more rapid adaptability in stochastic environments and protects the genome from the costs of adaptation which generally involve a reduction in genetic diversity and hence potential future adaptability. Predictions of distributed adaptability are proposed in relation to: a) biology and morphology, b) habitual behaviour, and c) feedback between behavioral change and biology. To evaluate these predictions in relation to a) we consider evidence for shifts in phenotypic plasticity and morphological variation, including the emergence of body and brain size variation, limb proportions, skeletal robusticity, and regional variation in plasticity and canalization within the body, and how these relate to environmental factors and dispersals. Predictions of behavioral change b) are considered in light of the emergence of spatial, temporal, and environmental variation in archaeological assemblages in the late Middle and Late Pleistocene as indicators of local adaptability, cognition and niche construction. Finally, we consider the relationships between dispersals and material culture, plasticity in response to cultural change, and variation in the microbiome in relation to c). Current evidence suggests a mosaic pattern of the evolution of distributed adaptation and selection within our genus. In early Homo there is evidence of phenotypic diversification and increasing plasticity that precedes evidence of increased cognitive, behavioral, and cultural variation of Middle and Later Pleistocene Homo. This can be interpreted as representing a shift towards the distribution of adaptability, first onto mechanisms based on phenotypic plasticity, and later onto cognition, cultural buffering of environmental stress, and enhanced niche construction. Phenotypic plasticity was likely an important component of adaptability to environmental stress, but also served to buffer development of the brain, an extended life history, and social learning.

Niche Construction, Cumulative Culture and The Social Transmission of Expertise

Kim Sterelny — Mon, 17 Oct 2022 00:00:00 +0200

This paper defends the following main claims: (i) in the discussion of cumulative culture, the importance of specific causal recipes has been overstated,and the imortance of broad-channel skills, and skills not tied to specific motor procedures has been understated; (ii) by the late Pleistocene, and probably earlier, hominin lives depended on broad channel skills and expertise. (iii) critical skills included those requiring specific physical procedures (toolmaking, hide preparation (and the preparation and use of other soft materials) but also more cognitive skills like tracking, local natural history, navigation. (iv) As these more cognitive skills are not ied to distinctive motor sequuencs, in-principle they cannot be learned by observing and reproducing the motor sequences of models. Even for those skills that do encompass specific physical skills, imitation of a model’s specific motor sequences is at most only one aspect of skill acquisition. The importance of imitation and other copying has been much over-stated in discussions of cumulative culture. (v) Rather than imitation or some other form of copying, the crucial cognitive capacity required for cumulative culture is the ability to integrate information streams from multiple social and physical channels. (vi) The reliable transmission of the cognitive capital of one forager generation to the next is supported by an adaptive, efficient learning niche.

Reconceiving Paleoanthropology in the Era of the Modern Evolutionary Synthesis

Matthew Goodrum — Mon, 17 Oct 2022 00:00:00 +0200

The Modern Synthesis was not widely adopted by paleoanthropologists until the 1950s, but the perception has been that this event had important theoretical and methodological consequences for the study of hominid evolution. This paper presents a general historical overview of the state of evolutionary theory within paleoanthropology during the early twentieth century, the key events that led to the integration of the Modern Synthesis into paleoanthropology, and the major consequences this had. Among the most important effects were the rejection of Neo-Lamarckian and orthogenetic mechanisms to explain hominid evolution. The Modern Synthesis emphasized genetics, the centrality of natural selection as the driving force of evolution, the notion that populations are highly variable, and that evolution produced gradually evolving lineages where the boundary between ancestor and descendant species is fuzzy. The Modern Synthesis encouraged the reform of hominid taxonomy, which resulted in the dramatic reduction of hominid taxa, and influenced hominid phylogeny through such ideas as the single species hypothesis. However, historians of science and paleoanthropologists have raised questions regarding the specific influences of the Modern Synthesis and the extent to which major developments in paleoanthropological theory and practice since 1950 should be attributed to the Modern Synthesis or to a more complex range of developments.

Let Sleeping Syntheses Lie

Ian Tattersall — Mon, 17 Oct 2022 00:00:00 +0200

As the twentieth century neared its midpoint, paleoanthropology was in dire need of revitalization and some coherent concept of evolution. Sadly, as introduced to paleoanthropology by Ernst Mayr in 1950, the Modern Evolutionary Synthesis proved disastrous in this role. Far from aligning the study of human evolution with the rest of paleontology, Mayr’s reductionist intervention merely alienated paleoanthropologists of all stripes from the systematics that must underpin all evolutionary biological inquiry; and it ultimately resulted in a minimalist taxonomy that did not admit adequate taxa to express systematic diversity within the rapidly expanding hominin fossil record. Since Mayr’s intervention, evolutionary biology has moved on, and it is clearly necessary to incorporate important subsequent advances (punctuated equilibria, genomics, epigenetics, multilevel selection, etc.) into paleoanthropological/paleontological practice. But to do so by grafting them onto the reductionist Synthesis will simply take us farther down the blind alley in which we are already mired, while doing nothing to fix the serious systematic problem. It is also necessary to be cautious in applying key components of the proposed Extended Evolutionary Synthesis to paleontological contexts. Developmental plasticity is, for example, always a potential complication when determining species in the fossil record; but as applied to hominins it has been taken to preposterous extremes, for example in justifying the shoehorning of a ludicrous variety of morphologies into the catch-all “species in the middle” Homo erectus: all in obeisance to the shade of Mayr, who likely had never seen an original hominin fossil.

13th Annual Meeting of the European Society for the study of Human Evolution Abstracts Aarhus, 21-22 September 2023

ESHE: European Society for the study of Human Evolution — Tue, 24 Oct 2023 00:00:00 +0200

ESHE Abstracts 2023.