Mobile containers in human cognitive evolution studies: Understudied and underrepresented.

Mobile carrying devices-slings, bags, boxes, containers, etc.-are a ubiquitous tool form among recent human communities. So ingrained are they to our present lifeways that the fundamental relationship between mobile containers and foresight is easily overlooked, resulting in their significance in the study of human cognitive development being largely unrecognized. Exactly when this game-changing innovation appeared and became an essential component of the human toolkit is currently unknown. Taphonomic processes are obviously a significant factor in this situation; however, we argue that these devices have also not received the attention that they deserve from human evolution researchers. Here we discuss what the current archeological evidence is for Pleistocene-aged mobile containers and outline the various lines of evidence that they provide for the origins and development of human cognitive and cultural behavior.

Playing with language, creating complexity: Has play contributed to the evolution of complex language?

We argue that enhanced play may have contributed to the emergence of complex language systems in modern humans (Homo sapiens). To support this idea, we first discuss evidence for an expansion of playing behavior connected to the extended childhood of modern human children, and the potential of this period for the transmission of complex cultural traits, including language. We then link two of the most important functions of play-exploration and innovation-to the potential for cumulative cultural evolution in general and for the emergence of complex language in particular. If correct, the shorter childhood of Neanderthals-involving restrictions on time to experiment and innovate-may have restricted their language (and other symbolic) system/s. Consequently, fully investigating the role that play may have had in the transmission of language and the development of symbolic cultures in both modern humans and Neanderthals provides a new avenue of research for Paleolithic archaeology and related disciplines.

Early human symbolic behavior in the Late Pleistocene of Wallacea.

Wallacea, the zone of oceanic islands separating the continental regions of Southeast Asia and Australia, has yielded sparse evidence for the symbolic culture of early modern humans. Here we report evidence for symbolic activity 30,000-22,000 y ago at Leang Bulu Bettue, a cave and rock-shelter site on the Wallacean island of Sulawesi. We describe hitherto undocumented practices of personal ornamentation and portable art, alongside evidence for pigment processing and use in deposits that are the same age as dated rock art in the surrounding karst region. Previously, assemblages of multiple and diverse types of Pleistocene "symbolic" artifacts were entirely unknown from this region. The Leang Bulu Bettue assemblage provides insight into the complexity and diversification of modern human culture during a key period in the global dispersal of our species. It also shows that early inhabitants of Sulawesi fashioned ornaments from body parts of endemic animals, suggesting modern humans integrated exotic faunas and other novel resources into their symbolic world as they colonized the biogeographically unique regions southeast of continental Eurasia.

42,000-year-old worked and pigment-stained Nautilus shell from Jerimalai (Timor-Leste): Evidence for an early coastal adaptation in ISEA.

In this paper, we describe worked and pigment-stained Nautilus shell artefacts recovered from Jerimalai, Timor-Leste. Two of these artefacts come from contexts dating to between 38,000 and 42,000 cal. BP (calibrated years before present), and exhibit manufacturing traces (drilling, pressure flaking, grinding), as well as red colourant staining. Through describing more complete Nautilus shell ornaments from younger levels from this same site (>15,900, 9500, and 5000 cal. BP), we demonstrate that those dating to the initial occupation period of Jerimalai are of anthropogenic origin. The identification of such early shell working examples of pelagic shell in Island Southeast Asia not only adds to our growing understanding of the importance of marine resources to the earliest modern human communities in this region, but also indicates that a remarkably enduring shell working tradition was enacted in this area of the globe. Additionally, these artefacts provide the first material culture evidence that the inhabitants of Jerimalai were not only exploiting coastal resources for their nutritional requirements, but also incorporating these materials into their social technologies, and by extension, their social systems. In other words, we argue that the people of Jerimalai were already practicing a developed coastal adaptation by at least 42,000 cal. BP.

Long range inland-coastal networks during the Late Magdalenian: evidence for individual acquisition of marine resources at Andernach-Martinsberg, German Central Rhineland.

Recent re-examination of the osseous material assemblage from Andernach-Martinsberg, Central Rhineland, has resulted in the identification of an implement manufactured from cetacean bone (probably whale). Argued to be the proximal half of a foreshaft, this artefact is not only one of few such projectile elements to be identified in Magdalenian deposits in northern Europe, but also demonstrates that the exploitation of marine raw materials for use in manufacturing projectile elements is not restricted to southern France, instead extending to at least inland Germany. Additionally, in conjunction with the appearance of marine molluscs and engravings of seals at Andernach, it can now be forcefully argued that this region formed part of an inland-coastal network during the Late Magdalenian and allows us for the first time to suggest that we can identify the movements of individuals transporting valued marine sourced raw materials and their personal experiences across this vast region.

Archaeological evidence for thinking about possibilities in hominin evolution.

The emergence of the ability to think about future possibilities must have played an influential role in human evolution, driving a range of foresightful behaviours, including preparation, communication and technological innovation. Here we review the archeological evidence for such behavioural indicators of foresight. We find the earliest signs of hominins retaining tools and transporting materials for repeated future use emerging from around 1.8 Ma. From about 0.5 Ma onwards, there are indications of technical and social changes reflecting advances in foresight. And in a third period, starting from around 140 000 years ago, hominins appear to have increasingly relied on material culture to shape the future and to exchange their ideas about possibilities. Visible signs of storytelling, even about entirely fictional scenarios, appear over the last 50 000 years. Although the current evidence suggests that there were distinct transitions in the evolution of our capacity to think about the future, we warn that issues of taphonomy and archaeological sampling are likely to skew our picture of human cognitive evolution. This article is part of the theme issue 'Thinking about possibilities: mechanisms, ontogeny, functions and phylogeny'.

Beyond the main function: An experimental study of the use of hardwood boomerangs in retouching activities.

Retouched lithic tools result from the functional modification of their edges following knapping operations. The study of the later stages of the reduction sequence is fundamental to understanding the techno-functional features of any toolkit. In Australia, a gap exists in the study of the chaîne opératoire of lithic tools shaped or re-shaped through percussion retouching. In our previous works (Martellotta EF., 2021, Martellotta EF., 2022), we have presented evidence for the use of hardwood boomerangs for retouching purposes in Australian Aboriginal communities. Through a detailed experimental protocol, the present study demonstrates how boomerangs can function as retouchers. We found that the use-wear generated on the boomerang's surface during retouch activity is comparable to retouch-induced impact traces observed on Palaeolithic bone retouchers, as well as to experimental bone retouchers generated in our replication experiments. Finally, we explore the role that microscopic lithic chips embedded in the retouchers' surface play in the formation process of retouching marks. Our results address the need for a deeper investigation of percussion retouching techniques in Australian contexts, opening the possibility that uncommon objects-such as boomerangs-could be used for this task. This concept also highlights the broader topic of the highly diverse multipurpose application of many Indigenous tools throughout Australia. At the same time, the study reveals a deep functional connection between osseous and wooden objects-a topic rarely investigated in archaeological contexts.

From small holes to grand narratives: the impact of taphonomy and sample size on the modernity debate in Australia and New Guinea.

Our knowledge of early Australasian societies has significantly expanded in recent decades with more than 220 Pleistocene sites reported from a range of environmental zones and depositional contexts. The uniqueness of this dataset has played an increasingly important role in global debates about the origins and expression of complex behaviour among early modern human populations. Nevertheless, discussions of Pleistocene behaviour and cultural innovation are yet to adequately consider the effects of taphonomy and archaeological sampling on the nature and representativeness of the record. Here, we investigate the effects of preservation and sampling on the archaeological record of Sahul, and explore the implications for understanding early cultural diversity and complexity. We find no evidence to support the view that Pleistocene populations of Sahul lacked cognitive modernity or cultural complexity. Instead, we argue that differences in the nature of early modern human populations across the globe were more likely the consequence of differences in population size and density, interaction and historical contingency.

Children and innovation: play, play objects and object play in cultural evolution.

Cultural evolutionary theory conceptualises culture as an information-transmission system whose dynamics take on evolutionary properties. Within this framework, however, innovation has been likened to random mutations, reducing its occurrence to chance or fortuitous transmission error. In introducing the special collection on children and innovation, we here place object play and play objects - especially functional miniatures - from carefully chosen archaeological contexts in a niche construction perspective. Given that play, including object play, is ubiquitous in human societies, we suggest that plaything construction, provisioning and use have, over evolutionary timescales, paid substantial selective dividends via ontogenetic niche modification. Combining findings from cognitive science, ethology and ethnography with insights into hominin early developmental life-history, we show how play objects and object play probably had decisive roles in the emergence of innovative capabilities. Importantly, we argue that closer attention to play objects can go some way towards addressing changes in innovation rates that occurred throughout human biocultural evolution and why innovations are observable within certain technological domains but not others.

Space to play: identifying children's sites in the Pleistocene archaeological record.

Identifying the residues of children's activities in deep time contexts is essential if we are to build a comprehensive understanding of human cognitive and cultural development. Despite the importance of such data to human evolution studies, however, archaeologists have only recently begun to look for prehistoric children's material culture, and the identification of children's spaces is completely absent for deep time contexts. This paper draws together sociological and historical data regarding the universal need of Homo sapiens children for 'secret' places - places away from parental control. These spaces are important for the behavioural development of children and are universal in modern contexts. This paper demonstrates that these features can be identified in prehistoric archaeological records - and as such - researchers will have new datasets with which to interrogate the role of children in the development of their respective societies.

Homo neanderthalensis and the evolutionary origins of ritual in Homo sapiens.

There is a large, if disparate, body of archaeological literature discussing specific instantiations of symbolic material culture and the possibility of ritual practices in Neanderthal populations. Despite this attention, however, no single synthesis exists that draws upon cognitive, psychological and cultural evolutionary theories of ritual. Here, we review the evidence for ritual-practice among now-extinct Homo neanderthalensis, as well as the necessary cognitive pre-conditions for such behaviour, in order to explore the evolution of ritual in Homo sapiens. We suggest that the currently available archaeological evidence indicates that Neanderthals may have used 'ritualization' to increase the successful transmission of technical knowledge across generations-providing an explanation for the technological stability of the Middle Palaeolithic and attesting to a survival strategy differing from near-contemporary H. sapiens. This article is part of the theme issue 'Ritual renaissance: new insights into the most human of behaviours'.

It's in the bag: mobile containers in human evolution and child development.

Mobile containers are a keystone human innovation. Ethnographic data indicate that all human groups use containers such as bags, quivers and baskets, ensuring that individuals have important resources at the ready and are prepared for opportunities and threats before they materialize. Although there is speculation surrounding the invention of carrying devices, the current hard archaeological evidence only reaches back some 100,000 years. The dearth of ancient evidence may reflect not only taphonomic processes, but also a lack of attention to these devices. To begin investigating the origins of carrying devices we focus on exploring the basic cognitive processes involved in mobile container use and report an initial study on young children's understanding and deployment of such devices. We gave 3- to 7-year-old children (N = 106) the opportunity to spontaneously identify and use a basket to increase their own carrying capacity and thereby obtain more resources in the future. Performance improved linearly with age, as did the likelihood of recognizing that adults use mobile carrying devices to increase carrying capacity. We argue that the evolutionary and developmental origins of mobile containers reflect foundational cognitive processes that enable humans to think about their own limits and compensate for them.

Portable art from Pleistocene Sulawesi.

The ability to produce recognizable depictions of objects from the natural world-known as figurative art-is unique to Homo sapiens and may be one of the cognitive traits that separates our species from extinct hominin relatives. Surviving examples of Pleistocene figurative art are generally confined to rock art or portable three-dimensional works (such as figurines) and images engraved into the surfaces of small mobile objects. These portable communicative technologies first appear in Europe some 40 thousand years ago (ka) with the arrival of H. sapiens. Conversely, despite H. sapiens having moved into Southeast Asia-Australasia by at least 65 ka, very little evidence for Pleistocene-aged portable art has been identified, leading to uncertainties regarding the cultural behaviour of the earliest H. sapiens in this region. Here, we report the discovery of two small stone 'plaquettes' incised with figurative imagery dating to 26-14 ka from Leang Bulu Bettue, Sulawesi. These new findings, together with the recent discovery of rock art dating to at least 40 ka in this same region, overturns the long-held belief that the first H. sapiens of Southeast Asia-Australasia did not create sophisticated art and further cements the importance of this behaviour for our species' ability to overcome environmental and social challenges.

Bows and arrows and complex symbolic displays 48,000 years ago in the South Asian tropics.

Archaeologists contend that it was our aptitude for symbolic, technological, and social behaviors that was central to Homo sapiens rapidly expanding across the majority of Earth's continents during the Late Pleistocene. This expansion included movement into extreme environments and appears to have resulted in the displacement of numerous archaic human populations across the Old World. Tropical rainforests are thought to have been particularly challenging and, until recently, impenetrable by early H. sapiens. Here, we describe evidence for bow-and-arrow hunting toolkits alongside a complex symbolic repertoire from 48,000 years before present at the Sri Lankan site of Fa-Hien Lena-the earliest bow-and-arrow technology outside of Africa. As one of the oldest H. sapiens rainforest sites outside of Africa, this exceptional assemblage provides the first detailed insights into how our species met the extreme adaptive challenges that were encountered in Asia during global expansion.

Specialized rainforest hunting by Homo sapiens ~45,000 years ago.

Defining the distinctive capacities of Homo sapiens relative to other hominins is a major focus for human evolutionary studies. It has been argued that the procurement of small, difficult-to-catch, agile prey is a hallmark of complex behavior unique to our species; however, most research in this regard has been limited to the last 20,000 years in Europe and the Levant. Here, we present detailed faunal assemblage and taphonomic data from Fa-Hien Lena Cave in Sri Lanka that demonstrates specialized, sophisticated hunting of semi-arboreal and arboreal monkey and squirrel populations from ca. 45,000 years ago, in a tropical rainforest environment. Facilitated by complex osseous and microlithic technologies, we argue these data highlight that the early capture of small, elusive mammals was part of the plastic behavior of Homo sapiens that allowed it to rapidly colonize a series of extreme environments that were apparently untouched by its hominin relatives.

An Enduring Shell Artefact Tradition from Timor-Leste: Oliva Bead Production from the Pleistocene to Late Holocene at Jerimalai, Lene Hara, and Matja Kuru 1 and 2.

In this paper, we describe 485 Oliva spp. shell beads recovered from four archaeological cave sites Jerimalai, Lene Hara, Matja Kuru 1, and Matja Kuru 2, located in Timor-Leste, Island Southeast Asia. While Pleistocene-aged examples of modified marine shells used for personal ornamentation are common in African and Eurasian assemblages, they are exceedingly rare in Southeast Asia, leading some researchers to suggest that these Modern Human societies were less complex than those found further west. In Timor-Leste, the lowest Oliva bead to be recovered was directly dated to ca. 37,000 cal. BP, making it the oldest piece of personal ornamentation in Southeast Asia. Morphometric, taphonomic, use wear, and residue analyses of these beads alongside modern reference specimens, and experimentally made examples indicate that the Oliva shells were modified to be strung consecutively (as in a necklace), and while their mode of production changed remarkably little over the thousands of years they were utilised, an increase in their deposition around 6,000 cal. BP suggests that there was a change in their use coinciding with sea-level stabilisation. These tiny beads demonstrate that early Island Southeast Asian societies produced the same kinds of symbolic material culture we have come to expect from the more intensively studied African/Eurasian region, and that limited sampling and poor recovery methods have biased our perspectives of this region.