For a paleogeography of childcare: Infant-carrying technics on a dynamic planet

What happens to the mundane practice of carrying infants if we situate it in the context of intensifying climate change and a deep past of geoclimatic instability? This article takes the resurgence of baby slings in the United Kingdom as an entry point into the deep, evolutionary history of child carrying and, in this way, as a prompt for an experiment in repurposing the field of paleogeography. This involves viewing the technics of the baby sling both as an aid to mobility and as a materialization of care relations. We extend this approach with the help of the cooperative breeding hypothesis which contends that communally shared childcare has been pivotal to human evolution and survival. We also draw upon theories that attend to the geologically dynamic landscapes of East Africa where humans evolved and the impact of long-term instabilities of global climate. Fusing these approaches while also accounting for critiques of evolutionary thought, we make a case that infant-carrying slings help facilitate a confident, outward-facing orientation both to worlds of complex social interactivity and to an Earth which is rifted, variegated and dynamic.


Introduction: 'Touch-and-go'
'It makes sense to me to keep them close . ... It's weird that we've gone away from that at any point.You know, from like [way back] people would wear shawls and things . . .even locally, you see old pictures with babies on their back when they are farming'.(Naomi) 'My mum . . .just kind of saying, "oh you need to . . .put him down in his pram you know" and "Oh your poor back".We were over at her house one time and we were going for a walk on the moors . . .and she just sort of looked at me and she said "I think I'll wear him [grandson]".She was a bit tired afterwards but she was really pleased with it . . .after that she changed her mind completely about slings . . . it was really nice, she got to wear him before she died'.(Christina) 'By the time we got into the car park . . .there was snow drifting in, it was absolutely chaos.So I thought 'right I'll get [baby daughter] inside', so I went to the car, I opened the back door, I got her out and it was snowing so hard I shoved her down my jumper.And I crossed the road like this to the front door and she was fast asleep and I thought 'oh''.(Jack) We begin our story locally.The aforementioned three excerpts come from a project carried out by one of us that looks at how carrying children in slings impacts upon family mobility (Whittle, 2019(Whittle, , 2022)).Based in Morecambe Bay and Sheffield in the north of England, the research brought into relief subtle shifts in the 'affective landscape of parenting' afforded by infant-carrying (Whittle, 2019: 146-148).As participants recounted, carrying infants close to the body -or 'baby-wearing' -brought together the practical advantages of hands-free, all-terrain conveyance with the sensual and affective pleasures of tactile contact.If not a panacea to the intense physical and emotional demands of caring for small humans, the recent upsurge of child-carrying slings in the study areas raised interesting issues around the way that combined pragmatic and affective affordances could be literally 'materialized' in simple devices.
The local aspects of the project, however, gestured towards grander scales.The constant allusion by participants to varied physical environments, such as hilly terrain and snowstorms in the aforementioned examples, served as reminders that landscapes of mobility are themselves uneven and shifting.To this we should add the prospect of still more unstable ground.Given the way that youthful activists are now insisting that their elders confront climate emergency, there is growing pressure to conceive of all intergenerational relationships in wider contexts of climatic uncertainty and change.From its concern with the relational implication of child-carrying in specific contemporary spaces, questions began to haunt the project of what it might mean to carry children into a turbulent, even catastrophic future.And as we began to confront changes now unfolding, we also found ourselves drawn to consider the geoclimatic instabilities of the past and the challenges they would have posed for looking after and conveying small humans.Spectral figures began to appear behind the baby-wearing families of Morecambe Bay and Sheffield, a great chain of caregiving bodies carrying children through deep time and across thresholds in the history of a dynamic planet.
As our opening quote exemplifies, many of the participants were aware of broader traditions of sling use.The idea that slings, wraps, pouches and cradle boards are routinely used in much of the nonaffluent world and have an extended human history is a staple of both popular literature advocating baby-wearing (Van Hout, 2008) and academic research into infant care (Schön and Silvén, 2007).'Infant carrying is a global but cross-culturally diverse practice', observes physiotherapist Chidozie Emmanuel Mbada et al. (2022: 535), before adding that it has become less common in the developed West as well as among some elites in the developing world.Evolutionary theorists, meanwhile, suggest that our infants 'are born with the expectation to be carried', a predisposition they claim we have inherited both from ancestral humans and the much longer lineage of primates (Berecz et al., 2020: 1).
Such spatial and temporal generalization of infant-carrying raises questions not simply about the current 'fashion' for holding and conveying babies close to the body (Berecz et al., 2020: 1) but also about the long-term attenuation of such practices in Western societies.Psychologists Regine Schön and Maarit Silvén (2007: 144-146) observe that significant changes in societal attitudes towards child-rearing parenting involving separate sleeping arrangements, tight discipline and avoidance of 'excessive' physical affection were well under way by the 18th century, although they also point towards older European 'cradle cultures'.Explanations offered for these changes are multiple, complex and hard to disentangle, and include the demands of industrial capitalism, the transition from extended to nuclear families, the rise of disciplinary societies and later, the medicalization of infant care.Less equivocal are observed transcultural differences in infant care, with studies showing pronounced variation in the amount of time infants are in close physical contact with caregivers between the contemporary West and other societies, especially those not heavily industrialized (Bánovský, 2023;Schön and Silvén, 2007: 144-146).An influential study showed that in two East African communities -one prominently hunter-gatherers, the other horticulturalists -babies spent some 79%-99% of their time being carried, held or touched.This compared with around 18% in a sample of Euro-American families (Hewlett and Lamb, 2002).
One manifestation of these changes, germane to our approach, is the rise of wheeled infant conveyances in the West: what we might see as the mobilization of the cradle or cot.The earliest recorded child-carrying carriage was commissioned by the Duke of Devonshire in 1733 (Bellis, 2020).By the 1830s, baby carriages were being manufactured in the United States, while perambulators or 'prams' gained popularity in Victorian England, boosted by Queen Victoria's patronage (Sewell, 1923).The basic template prevailed until aeronautical engineer Owen Maclaren built a collapsible aluminiumframed 'stroller' in the 1960s, which has subsequently been developed into a range of lightweight threeand four-wheeled buggies -some of which can be switched from prone to seated-position (Hann, 2002).
Just as early perambulators belonged to an era and a social positioning in which horse-drawn vehicles prevailed, the foldaway buggy fitted snuggly into the more socially inclusive and increasingly globalized automotive regime of the latter 20th century.Yet automobility itself has come to manifest an ambivalent relationship to physical environments whose looming instability it has helped induce (see Urry, 2004).Like the four-wheel drive vehicles in which they are often conveyed, many latemodel baby buggies are designed for uneven surfaces.Weather-shielded, seat-belted and riding on shock absorbers, the early-millennial infant, it might appear, is being readied for whatever turbulence lies ahead.But the environmental defiance and rugged individualism of the all-terrain buggy, we suggest, are far from the only mobility option for conditions of topographic and existential inconstancy.
Our concern with securing the child for a bumpy ride is likewise geographically and historically situated.But as we have indicated, our scope is a broader geography and a longer, more jarring history than that of wheeled infant mobility.In this article, we explore connections between 21st century baby sling users and their hominin 1 predecessors who, it has been surmised, learned to bind infants to their hips or backs, long ago, in the east of the African continent (Berecz et al., 2020;Nowell, 2021: 33-34).Whereas our proximate baby-wearers face a choppy exit from the epoch geologists refer to as the Holocene, their deep-time counterparts must have carried their children through the vacillating climatic conditions of the Pleistocene and perhaps the still-earlier Pliocene (Hrdy, 2009a: 230).And yet, although these infant caregivers are worlds apart, the basic functionality of the sling may well have barely changed, as if the technics of care have themselves folded in time like a pelt or swatch of fabric.
It is worth keeping in mind that of the various species comprising the genus Homo -current estimates range between 9 and 17 -Homo sapiens are the sole survivors.Until the waning of the last ice age, notes anthropologist Sarah Blaffer Hrdy (2009b: 6), the survival of our own species was 'touchand-go'.'Touch-and-go', for us, speaks not only to the precariousness of the human genus throughout most of its roughly two-million-year span but also evokes the connection between tactility and mobility that characterizes the baby sling.And a practical and affective technics for conveying human youngsters, we speculate, may have played a significant role in surviving the geoclimatic upheavals of the last couple of million years.
Hrdy's work is central to our argument.Over several decades, she and associated researchers have been making the case that a definitive characteristic of humans is the collective way they raise their infants -an argument fusing insights from psychology with evolutionary biology.Unlike near-relative great apes, Hrdy contends, human mothers routinely share care and provisioning of their offspring with others: a variation on a more general practice biologists refer to as cooperative breeding (Cant, 2012).It is onto this basic behavioural and evolutionary framework that we speculatively graft the input of infant-carrying technics.A detachable means of tethering a child to any of its caregivers, we propose, facilitates processes of cooperative rearing.Moreover, the positioning of the child high on the body of its carrier is believed to amplify the opportunity for infants to observe and participate in the social interaction of their seniors (Bánovský, 2023;Knowles, 2016).In this way, we attest to the value of a deep temporal perspective on questions of human infant mobility and the spaces of care and affection in which it is implicated -a move that would hardly surprise our physical geography colleagues.As human geographers, however, we want to do more than simply strap our own analysis onto the pre-existing body of evolutionary anthropology.What contemporary human geography and cognate disciplines invested in relational ontologies bring to an understanding of deep temporal childcarrying, we propose, is an attunement to the way affective relations, the materiality of social objects and the more expansive physicality of inhabited spaces come together.How do loving and caring dispositions come to be 'materialized' both in human bodies and in the extra-somatic devices humans construct, we ask, and how are these 'matters of care' (Puig de la Bellacasa, 2011; 2017) implicated in diverse and shifting landscapes?
It also matters, we argue, that the likely site at which the child-carrying devices were first devised was topographically diverse and geologically active; that the technics of infant mobility emerged in the context of an Earth that is itself mobile.Here we draw upon the complex topography hypothesis advanced by geophysicist Geoffrey King, archaeologist Geoff Bailey and others which proposes that the tectonically active environment of the East African Rift Valley played a crucial role in early hominin evolution (King and Bailey, 2006; see also Clark et al., 2018).Not only did the Rift Valley provide important resources for a ground-dwelling primate, this approach also suggests the challenge of 'scrambling across a complex 3D terrestrial landscape' played a formative role in the evolution of hominin bipedal locomotion (Winder et al., 2013: 8).
Despite the resonance of negotiating 3D terrain and the more general question of putting social and physical dynamics into conversation, it is still relatively unusual for human geography to delve into geological and evolutionary timescales.Too often, human geographers and fellow critical social thinkers assume that addressing such grander spatio-temporal scales implies a depreciation of 'placebased', 'lived' or 'embodied' experience (Clark and Gunaratnam, 2017;Clark and Szerszynski, 2021: 35-38).To address such concerns, we take inspiration from historian-anthropologist Gabrielle Hecht's (2018) notion of 'interscalar vehicles' to affirm the possibility of articulating between situated human lives and the extensive reaches of geological existence.The baby sling is such a vehicle, we propose, that literally and metaphorically enfolds, knots or binds the most intimate human acts to the enormity of the dynamic Earth.
At a juncture when Earth system change is high on scientific and political agendas, we are interested in the wider disciplinary implications of such a hitching together of tiny, impressionable bodies and a planet on which 'variability abounds at nearly all spatial and temporal scales' (Steffen et al., 2004: 295).If, according to philosophers Gilles Deleuze and Felix Guattari's (1994) reading of the work of historian Fernand Braudel, all 'history is a geohistory' (p.95), then perhaps it is time to consider whether all of human geography is at least potentially paleogeography.It seems to us that paleogeography -the Earth science subfield concerned with the changing configurations of continents, magnetic fields and other planetary components in deep geological time (Meinhold, 2019;Ross, 1999) -might take on new meanings both as the category of the 'paleo' expands to embrace transformation of the geophysical Earth currently underway and as social and cultural thinkers become more willing to dig deep into the prehistory of our matters of concern (see Barnosky, 2014).
We view this as part of a broader conversation, particularly with archeaologists Shumon Hussain and Felix Reide's (2020) recent proposal for a 'paleoenvironmental humanities' which seeks 'to align the rich, long-term archeological datasets on human-environment interactions with issues, concepts, and concerns of the emerging environmental humanities and the climate change debate at large' (p. 6).At the same time, we are deeply aware, as are many researchers in the field, that Euro-modern accounts of human origins and the gathering of evidence to support these stories have been constitutively implicated in the violence of geopolitical and epistemic coloniality.As paleobiologist Pedro Monarrez et al. (2021) assert: 'Western paleontology did not develop independently from, or parallel with, racism and colonialism but has been intertwined with them throughout its history' (p.2).With this firmly in mind, however, we also affirm that deep-time perspectives on human evolution and planetary change offer resources that can help destabilize narratives that promote or assume European supremacy (Gunaratnam and Clark, 2012).A wide-angle lens on infant-carrying not only brings into relief a world of practices that have been occluded by certain western assumptions about infant care, as intimated earlier, but also raises questions about the implication of these Euro-modern conventions and related experiences in the unfolding of the current global environmental predicament.
Our exploratory paleogeography sets out from a scoping of how infant mobility fits into current concerns of human geography and neighbouring disciplines, taking this as an entry point to a review of what 'paleo-focused' disciplines have to say about hominin child-carrying practices.We then take a closer look at how the technics of the baby sling serve to materialize intimate expressions of love, care and sensuality, in the light of the cooperative breeding hypothesis.In the subsequent section, informed by the complex topography hypothesis, we explore the relationship between the evolution of child-carrying and the mobility of the Earth itself.By way of conclusion, we consider both drawbacks and advantages of thinking in evolutionary terms and point to the prospects of a repurposed paleogeography for navigating imminent thresholds in Earth systems.

Theorizing infant mobilites in the present and past
Even before taking the deep temporal plunge, the question of how we transport our offspring brings together multiple current concerns of human geography and cognate disciplines.It draws us into considerations of mobility, specifically in relation to reproduction, infancy and family life, which brings us to thematics of care, affection and sensuality and the material objects that support practices of moving and caring.A previous publication by one of us reviews and integrates key contributions from these literatures (Whittle, 2019).As this article shows, research on infant and family mobilities tends to focus on modes of 'wheeled' mobility prevalent in higher income regions, notably prams (Boyer and Spinney, 2016;Jensen, 2018) and cars (Dowling, 2000).Such work usefully shifts attention from powerful urban and corporate space-shaping actors towards more mundane and variegated familial groups.It helps us to move beyond parental experience to embrace child-centred perspectives and the agency of children -a growing concern that geographers (Holt, 2013) share with anthropologists and archaeologists (Hrdy, 2009a;Lillehammer, 1989;Nowell, 2021: 7-13).The call to 'rethink the right to the city as co-constituted through the relationships between spaces, prams, routines, routes, subjectivities and (non)humans encountered when out and about' (Clement and Waitt, 2018: 253) seems to us equally relevant to mobilities configured around contemporary baby-wearing (see Whittle, 2019: 141).There is also a lively interest in walking in human geography (Kärrholm et al., 2017;Lorimer, 2011;Stratford et al., 2020;Wylie, 2005), although such work has rarely considered conveying infants as a key component of pedestrianism.
While much 'wheel-based' literature attends to caring and affective aspects of infant mobility, we would stress that a turn to mobilities centred upon tactile contact significantly reconfigures the emotional and sensory dimensions of child-caregiver relations.In this regard, feminist concerns with the ethics, aesthetics and carnalities of care offer rich resources.Since at least the early 1980s, feminist researchers have been exploring 'ethics of care' as a counterpoint to prevailing critical concerns with justice, rights and utility, while contesting assumptions that women's 'natural fecundity' and nurturing impulses predispose them to caregiving roles (Gilligan, 1982;Tronto, 1987).Taken up in human geography, such themes have been elaborated into inquiries about how care is embedded in social networks and how it gets extended through time and space, along with more general questions about the role of intimacy and affect in the shaping of socio-spatial relations (Barnett, 2013;Conradson, 2003;Valentine, 2008).Here too there are important parallels with archaeological research into deep histories of care and compassion (Spikins et al., 2010).
As Gill Valentine (2008) proposes: 'the hinge that links geographies of sexualities, children, young people and parenting together is affective structures or intimate relations' (p.2102), an observation lending itself to reflecting on the literal 'hinging' between bodies performed by sling technics.The rhythm of caregiver's walking, the echo of heartbeats, sharing bodily warmth and skin-to-skin contact -what anthropologist Diana Adis Tahhan (2010Tahhan ( , 2013) ) refers to as 'skinship' -resonate with the sensuous, intercorporeal nature of care foregrounded by feminist scholarship (Diprose, 2002;Lupton, 2013).Such concerns are attuned to the asymmetrical gendering of caring relations, while acknowledging the multiple, polymorphous ways in which give and take between bodies plays out.So too should we heed the cautionary note sounded by feminist and queer theorists that caring for another can be misdirected, disappointing, overwhelming or otherwise 'unbearable' (Berlant and Edelman, 2014;Diprose, 2002: 190; see also Anderson, 2022).
Our understanding of baby slings as technics of care takes further cues from science and technology studies (STS) scholar Maria Puig de la Bellacasa's (2011, 2017) merger of feminist care ethics with the STS interest in extrusion of social agency into durable 'things'.She calls upon us to attend to the processes by which caring relations can become sedimented into everyday objects, devices and technologies.Supplementing Bruno Latour's (2004) 'matters of concern' with 'matters of care', Puig de la Bellacasa (2011) suggests, is especially urgent in the context of worlds that appear ever more precarious, damaged and 'aching' (p.100).Here we pick up resonances with Hecht's (2018) notion of tools, tactics and practices which connect up scales and narratives that seem otherwise incommensurate: 'interscalar vehicles' whose careful construction and deployment might just help us to 'de-escalate disaster' in rapidly changing physical worlds (p. 134, 115).
We approach slings as a supple and pliant 'concretization' of dispositions of care for an impressionable infant, while considering sling-enabled caregiving as both figure and practical means of negotiating with a not-necessarily compliant wider world.But as we set about spatio-temporally scaling up the knotted-together journey of child and caretaker, it soon becomes apparent that much contemporary thinking about mobility and care lacks the desired reach.As human geographer Andrew Baldwin et al. (2019) observe: 'the movements that concern the mobility paradigm are mostly to do with people, objectives, technologies, knowledge, and capital . ... the physical surface of the Earth over which movement is understood to occur, is for the most part inert' (p.292).With few exceptions, they note, studies of mobility fall short of the scalar and dynamical compass that would allow the mobilization of the planet itself to enter into accounts of people in motion (but see Clark, 2017;Szerszynski, 2016).A related point could be made about the evolutionary aspects of human mobility or locomotor activity.Analogously, while much contemporary work on ethics and technics of care stretches beyond human realms and into wider 'ecological' entanglements, it is rarer to see close consideration of a changeable Earth as a site of or an incitement to care (but see Clark, 2011) or to see sustained consideration of the evolution of human empathetic capacities.
Exit the social sciences conventionally concerned with 'modernity' and enter those disciplines that specialize in the 'paleo' domains, and unsurprisingly the emphasis shifts.In human biology, anthropology and archaeology, evolution of human locomotion, reproductive practices and child raising are such prominent concerns that we can offer only a brief overview here.As with the research we surveyed previously, much of this work is inflected by broadly feminist concerns, if not always explicitly (see Hager, 1997;Wylie, 1997).Taking issue with the 'Man the Hunter' paradigm that consolidated in the 1950s and 1960s, a model that largely relegated prehistoric women to sexual receptivity, childraising and hearth-bound domestic drudgery, several generations of mostly but not exclusively female paleoanthropologists countered by stressing the active, inventive and flexible roles played by women in the hominin story (Hager, 1997;Zihlman, 1997).
Central to this turn was a reassessment of the contribution of female foraging as complex, knowledge-intensive and nutritionally indispensable.Foraging, reported paleoanthropologist Lori Hager (1997), required the skill of 'orienting oneself in three-dimensional space' (p.8) -a point to which we will return.With the attribution of increasing mobility and versatility to prehistoric women came growing interest in how they conveyed their offspring.Along the way, research into child-carrying has had to reckon with the uneven survival of hides, fabric and other perishable organic materials relative to stone tools (Berecz et al., 2020), while also contending with the male hunting paradigm's prioritizing of technics associated with acts of aggression over those that facilitated care.
Much of this scholarship is speculative, and key claims are highly contested.Evolutionary theorists contextualize human or hominin infant-carrying within the broader frame of primate evolution -proposing that 'our' practices are variations on the theme of ventral (on the back) conveyance of fur-clinging infants, which has been a definitive chartacteristic of primate behaviour for much of the last 55 million years (Ross, 2001).At a certain point, most often associated with upright walking or bipedalism and thinning of body fur, ventral carrying was succeeded by lateral (or side) carrying of infants with manual support from the caregiver (Bánovský, 2023;Nowell, 2021: 33-34).The timing and dynamics of this shift are complicated, not least by evidence that hominins continued to be occasional tree climbers -with markedly different challenges for infant-carrying than ground-based locomotion -for several million years after they became upright walkers (Berecz et al., 2020).
When and why lateral carrying of infants came to be supplemented by supporting devices is likewise controvertible.Biological anthropologist Cara Wall-Scheffler et al. compared the energetic expenditure of walking long distances carrying an infant in the arms with journeys made using a sling that left the arms free.A significant difference -savings of around 16% -led them to conclude that the energetic drain of carrying an infant would be such that some sort of carrying device would have been required soon after the development of bipedalism and definitely to allow long distance travel, especially that out of Africa and across Asia (Wall-Scheffler et al., 2007: 841; see also DeSilva, 2011).
There are, however, concerted arguments for a later uptake.Associating sling invention with the evolution of the human brain and language skills, biologist Berecz et al. (2020) favour a starting point around the time of the emergence of Homo erectus some two million years ago.Archaeologist April Nowell largely concurs.'There is no evidence of fibre technology before Neandertals', she argues, 'and certainly nothing about early hominin material culture suggest carriers were in use before H. erectus at the earliest' (Nowell, 2021: 34).
While the timing of sling invention remains contentious, the broader terms of the debate inherit much from the disenthrallment with 'Man the Hunter' narratives.For those researchers reconsidering women's roles, it has long made sense to credit female foragers with the earliest tool invention (Hager, 1997: 6).In the mid-1970s, feminist anthropologist Elizabeth Fisher (1979) surmised that the first cultural device was a sling or bag for carrying foraged foodstuffs: a basic model that could well have been extended to conveying infants (see Le Guin, 2019).It is worth recalling, however, that stone tools retain much of their centrality in human origin stories, with recent discoveries extending the earliest stone tool use to 3.3 million years ago, some half a million years before Homo's currently calibrated appearance (Maslin, 2017: 23-24).Questions remain as to why hominins capable of shaping stone could not have requisitioned hides, plant fibres or other available materials to help support a child on the hip.
Perhaps the thorniest issue in the evolution of hominin child-carrying is the relationship between the conveyance of infants and developments of brain capacity and, by extension, intelligence.Giving birth to larger-brained, bigger-skulled babies poses what evolutionary theorists refer to as the 'obstetrical dilemma' of requiring a broadening of the pelvis which would in turn compromise bipedal locomotion (Isler and Van Shaik, 2012).Infant-carrying in general, and sling-assisted carrying in particular, it has been argued, helps resolve this problem by facilitating the extended gestation of the infantwith further skull enlargement -outside the womb (Taylor, 2010: 127-134;Knowles, 2016).Recent research, however, contests claims for a trade-off between pelvic breadth and erect walking (see Berecz et al., 2020;Nowell, 2021: 23-28).Although operating outside our disciplinary comfort zone, we are inclined to follow Hrdy and fellow cooperative breeding theorists whose explanation for expanding brainpower prioritizes not a technical breakthrough but the socio-cognitive inventiveness associated with collaborative child-rearing.'Creatures may not need big brains to evolve cooperative breeding, but hominins needed shared care and provisioning to evolve big brains' asserts Hrdy.'Cooperative breeding had to come first' (Hrdy, 2009a: 277; see also Burkart et al., 2009;Isler and Van Shaik, 2012).
Evidence for the primacy of distributed and flexible caring relations in nudging forward hominin cognitive evolution suggests that we consider the physical attachment of infants to caregivers in the broader context of their affective attachment to multiple caring others.In the following section, we examine how child-carrying slings function as 'materializations' of cooperative childcare and its associated cognitive-affective dispositions.

Baby slings as technics of cooperative childcare
Among societies that have persisted with infant-carrying, there is much observed difference in styles, devices and practices: variations that have been attributed to both infant care customs and environmental factors such as climate (Schön and Silvén, 2007: 145-147).Across much of Africa, infantcarrying on the back is the norm, for example, side or lateral slings are more common in East Africa and on Pacific and Indian Ocean islands, while front-carrying positions are popular in resurgent Western traditions (Mbada et al., 2022).What cooperative breeding theory directs our attention to, however, is the matter of who is doing the caring and carrying -and the implications of this for the experience of the child.
It is worth noting that child-carrying technics are not as prominent in Hrdy's cooperative breeding narrative as they are in accounts with a more technical or locomotor focus.But they do pop up at opportune moments, for example, in an account of a Hadza mother strapping her infant to a 'protesting unrelated girl' and in a captioned photograph of !Kung babies slung to the back of older children (Hrdy, 2009a: 205, 274).The anecdote and image drive home Hrdy's point that infant caring is characteristically distributed beyond the immediacy of child-mother couplets.This too was apparent in the findings of our Morecambe Bay-Sheffield sling-use study (Whittle, 2022).Neither the grandmother from our second opening quote nor the father who spontaneously adopted babywearing in a snowstorm were exceptional.Resistance to slings among relatives and others more habituated to prams and pushchairs was frequently reported, although as the following excerpts suggest, experiencing the benefits of slings can encourage their adoption: 'because I'm there all the time . . .she does struggle to settle with other people but as soon as she goes in the sling, wherever she is she settles.So . . .my husband and my Mum has done it as well, despite the fact she didn't really agree with it, she's put her in the sling and she settles straightaway . . .it's brilliant'.(Claire) 'I think there's a . . .growing awareness and acceptance at the nursery . . .that sling is . . .a useful tool and that parents are into it . . .So . . .when Fionn arrived to . . .get him to sleep they put him in a sling a little bit.So they want to get some nursery slings and they've asked us if we could leave Fionn's sling there for them to use'.(Brendan) If we are to situate such experiences in a broader evolutionary context, it is important to note that they gesture not only beyond our era but also beyond our species and genus.While prosthetic infantcarrying aids may be human innovations, cooperative breeding -or routine nonparental care of offspring -is well-documented in a range of species including insects, fish, birds and mammals (Cant, 2012).While small primates such as marmosets are consummate cooperative breeders or 'alloparental' carers, among the great apes, care of offspring and food provisioning is overwhelmingly performed by the mother (Hrdy, 2009a: 92-99).Hominins diverge from great apes both in their willingness to share infant support among a range of community members and in the regularity with which food is collectively distributed.The combination of alloparenting and shared provisioning, Hrdy and others suggest, made it possible for hominin mothers to bear children at shorter intervals than their great ape relatives, while enabling the energetically 'expensive' evolutionary innovation of larger brains (Hrdy, 2005(Hrdy, , 2009a: 275-277;: 275-277;Burkart et al., 2009).
But this makes it sound rather mechanical.What Hrdy and her colleagues emphasize is that collective breeding both enables and encourages the infant to 'appeal' to potential carers.From almost the moment of birth, human infants are communicatively responsive to faces, sounds and gestures.In this way, newborns contribute actively to making their own care 'bearable' to others, and from then on, they rapidly acquire capacities for 'reading' the minds and moods of potential caregivers, which serves to increase the likelihood of being looked after (Hrdy, 2009a: 37-57, Hrdy andBirkett, 2020).These 'hypersocial' capabilities, it is argued, are at the very core of what makes us human, the cognitive foundations of all our other collective, intersubjective achievements (Hrdy, 2004).
All of which means that the male-female pair-bonding axial to the Man the Hunter paradigm is decentered and complexified.What tips the evolutionary balance is the presence of extramaternal caretakers -allomothers or alloparents -especially but not only female kin (Hrdy, 2009a: 250-264).Evidence shows that relative to other primates, hominin post-reproductive female longevity is exceptional.Surviving grandmothers, it is argued, may have been every bit as helpful as spear-wielding male partners, especially given the value of the lifelong foraging experience of aging females under environmentally challenging circumstances.In sum, 'vigorous senior women earned more descendants by feeding grandchildren' (Hawkes et al., 1998(Hawkes et al., : 1336;;cf Kachel et al., 2011).Keeping in mind that for humans and other primates, infant transport is second only to lactation as an energetic demand on mothers (Gettler, 2010), it also makes sense that elder kin would have shared carrying duties.And especially in the case of both older and younger 'allocarers', the energy-saving contribution of the sling might have been crucial: recalling our grandmother in the opening quote, tired yet content after carrying her grandchild across the moors.This is more than a matter of allomothering.Both the behavioural and physiological appeal of care-attracting capabilities look to have crossed gender divides -and continue to do so.Evidence suggests that close contact with infants triggers hormonal as well as emotional responses in all humans.In the case of mature males, researchers note, this results in discernible lowering of testosterone levels, which in turn encourages affectionate rather than aggressive behaviour (Hrdy, 2001(Hrdy, : 95-96, 2009a: 99;: 99;Gettler, 2010).Our observed willingness of contemporary males to 'wear' infants, it seems, is more than a late modern trend.As anthropologist Lee Gettler (2010) observes, direct male care of infants is much more prevalent in many human populations than in other primates, especially great apes.Elaborating on the idea that sexual divisions of labour were less entrenched earlier in human evolution, Gettler (2010) concludes 'early Homo males were, at very least, likely candidates to carry young in the course of foraging outings, leading to a reduction of maternal metabolic costs ' (p. 14).
Then there is the contribution of infants themselves.As we have seen, a point of convergence among researchers exploring contemporary 'infant geographies' and those working in the field of the evolution of human child-raising practices is a concern with the experience, perspective and agency of children themselves.Both the cooperative breeding paradigm and our own observations suggest that there is a lot more going on in sling use than simple substitution for the loss of the fur that other infant primates cling to.Moist skin, proposes Mel Cyrille (2018), has adhesive properties.This is aided by the child's own efforts -for their primate relatives, human infants are 'active clinging young' (Berecz et al., 2020).Still more important is the active contribution of infants in soliciting care: the intimate investment that, as Hrdy (2009a: 72-73, 119-121) reminds us, cannot be taken for granted even from the mother. 2Even very small children, cooperative breeding theorists note, are adept at emitting and interpreting signals that indicate another's potential to provide care -a skill that has been observed in infants born sightless (Hrdy, 2009a: 60;Hrdy and Birkett, 2020).More than any other capability -it is this hyperbolic capacity to read and respond to affective states of numerous fellow beings, argues Hrdy (2009a: 28-29), that has made us the genus and species we are.
If, as Hrdy (2009a) concludes, 'infants nurtured by multiple caretakers grow up not only feeling secure but with better-developed and more enhanced capacities to view the world from multiple perspectives' (p.132), it is the sling that literally offers the platform for the profuseness of juvenile hominin experience.What is extruded and concretized in the technics of the sling is the affordance of sharing a world of complex affective communication -an intensity of sensory immersion of the infant that is unmatched by the experience of lying in cradles, prams or even state-of-the art buggies.As a 'matter of care', what matters most is the combination of inward-facing tactile contact and outward-facing communicativity: the feeling of being at once physically secure and constantly challenged by the complexity of grown-up sociality.More than an energy-saving device that allows ambulant carers to swing their arms and more than a means of sharing body warmth, we contend, the child-carrying sling is a technic for fostering curiosity -a facilitator of self-amplifying socio-cognitive development.

Sustaining life on terra mobilis
The fact that 'we' Homo sapiens exist at all suggests the arrangement was effective, even if survival was a more fortuitous byproduct than primary intention.In this section, we look more closely at temporal and spatial factors, including changes in the Earth, that come into relief as our geographical horizons expand.As we saw earlier, much research on early hominin child-carrying still seems to assume relatively even terrain, while infant mobility research in human geography has addressed variable terrain but without a deep temporal perspective.An approach that contextualizes human evolution in landscapes contoured by active tectonics, we suggest, usefully brings these perspectives together.
The complex topography hypothesis proposes that the dynamic environment of the Rift Valley offered multiple attractions for rapidly evolving primates, including fresh-water, fertile soils, diverse ecosystems and platforms from which to observe and trap prey (King and Bailey, 2006).Researchers further link this milieu to the evolution of bipedalism, making a case for scrambling as the vital intermediary between primate arboreal locomotion and hominin erect walking.It is not the demands of moving across grassy plains, primatologist Isabelle Winder et al. (2013) argue, but the challenge of clambering over rugged ground that best explains the anatomical features of early bipedal hominins and their divergence from other primates.Climbing over rocky terrain, they explain, took advantage of the upper-limb grasping ability of tree-dwellers, while selecting for arched, weight-bearing feet with lever or springing functions.Only later, as lower limbs grew more suited to striding, did hominins venture onto the savannah.In short, 'transition from climbing in a complex 3D arboreal environment to scrambling across a complex 3D terrestrial landscape' makes more sense than fast-forwarding from forest to flatland (Winder et al., 2013: 8).From a reproductive point of view, complex topography theorists add, Rift Valley landscapes offered both a profusion of high-quality brain-feeding nutrients to the skilled forager and a range of nesting sites relatively safe from predators, affordances which Winder et al. (2013) suggest facilitated the appearance of the modern human life history with its extended childhood and shorter interbirth intervals.They also propose that enhanced propensity for carrying, assisted by shortening arms, was a useful byproduct of other developments.
The 'scrambling' aspect of the complex topography hypothesis, we speculate, has implications for considering carrying practices in general and infant-carrying in particular.With regard to the task of gathering, the routine requirement for conveying foodstuffs from foraging grounds to hard-to-access base camps lends support to the foregrounding of carrying devices.Likewise, the demands of clambering suggest that benefits of infant-carrying aids might be as much about freeing up hands as about more energy-efficient striding.So too must we keep in mind that this topography was rugged and variegated because it was geologically active.To speak of mobility over the terrain in question is to invoke terra mobilis (Clark and Szerszynski, 2021: ch 6): the ongoing activity of seismic and volcanic processes, shifting hydrology and slope morphology, the pulsing of fire and ecological succession.For a primate whose physiology required constant hydration, water bodies were likely to have been essential (Stein, 2007), presenting the challenge of carrying both water and infants.This would also have been a matter of navigating hydrological landscapes in transition, for as geologists remind us '(f) reshwater lakes within rift valleys were repeatedly created and destroyed by continuous morpho-tectonic adjustments' (Gani and Gani, 2008, see also Maslin and Christensen, 2007).Although it has long encountered spirited resistance from defenders of the 'savannah hypothesis', the idea that early hominins spent much of their time around and immersed in water bodies is also being reassessed in the light of the growing emphasis on tectonically active topography (Calvin, 2002: 148, 88-89;Stein, 2007).This in turn situates infant-carrying technics in a context of wading, fording rivers and encountering intermittent flooding, as a complement to the demands of rock climbing.
In the still bigger picture, we should recall Hrdy's assertion, in reference to Pleistocene climate fluctuation, that hominin survival was 'touch-and-go'.Formulated around the same time as the active tectonics paradigm, the abrupt climate change hypothesis spotlights the devastating rapidity of past global climate change.'Our ancestors lived through hundreds of such episodes', notes evolutionary psychologist William Calvin (2002: 3) '-but each became a population bottleneck, one that eliminated most of their relatives (see also Burroughs, 2005: 99, 136).Cooperative breeding, suggests Hrdy, was a key to the survival of the hominin lineage that eventually branched into Homo sapiens.However, she also notes that any claim that 'the late Pliocene-Pleistocene crucible of unpredictable climate change with recurring periods of food shortage' served as a stimulus for shared child-rearing and collective provisioning among ancestral humans raises questions about why nonhuman primates did not adopt similar strategies (Hrdy, 2009a: 230).
While there is no simple answer, Hrdy (2009a: 250-254) draws attention to the pivotal role of the mother's matrilineal kinfolk -grandmothers, great-aunts and others -a contribution enabled by increasing hominin lifespans compared to other primates.In turn, this relative longevity may have come down to hominin foragers learning to exploit a widening range of food sources and developing ways to pass on this information and skill to younger group members (Hrdy, 2009a: 256-257).At the same time, Hrdy (2009a: 270-272) adds, providing opportunities for bonding between infants and older kin would likely have played a part in cultivating shared caretaking propensities.Here too, as we glimpsed earlier, human babies are active participants, deploying sophisticated capacities for eye contact, imitation and reading others' intentions that far outstrip fellow primates (Hrdy, 2001: 98).
If this penchant for intercommunicative 'hypersociality' helped forge specifically hominin trajectories through epochs of whiplash climate change, we can see how child-carrying devices -by facilitating foraging and enhancing infant participation in the world of intensive social exchange -may have played a significant 'supporting' role.We would also stress the importance of experiences of the physical environment that exceed mere survival, while recalling the diversity and dynamism of the Rift Valley milieu.A child perched on a caregiver's hip or back while they went about provisioning journeys would have likely experienced both a profusion of activities -climbing, wading, digging, picking, small-game hunting -and an exceptional range of landforms and lifeforms.Such mobile, multisensory encounters would not only have stimulated infant cognitive development but, from the secure vantage point of tactile contact, also would have likely inspired confidence and trust amid changeable environments.In other words, if '(c)are-taking inscribes new pathways in the brain' (Hrdy, 2001: 76-77), this would have been enhanced by the fact that caretaking was performed literally along intriguing and invigorating pathways.
Working with more contemporary hunter-gatherer communities in the 1950s, psychologist Jean Liedloff noted how child-raising among the Amazonian Yequana people involved constant contact with caregivers while they engaged in sensorially rich daily activities.Of the Yequana infant, she observed, 'a great quantity and variety of experience come to him through his adventures in the arms of a busy person' (Liedloff, 1986: 44).Linking such experience to the deep continuum of human evolution, Liedloff (1986) argued that everyday encounters with the sensory stimuli of '(t)hunder and lightning, barking dogs, deafening roars of waterfalls, splitting trees, flaring fires, surprise dousings in rain or river water' for a small child held by or strapped to its mother built the foundation of youthful confidence in the face of a challenging physical world (p.46).Conversely, she noted the debilitating effect on the 'civilized' child of being routinely detached from its primary caregiver's body and parked alone in a cot or pram, bereft of sensory immersion in the 'stream of life' (Liedloff, 1986: 83). 3  Add rocky outcrops, volcanoes and seismicity to the mix, and Liedloff comes close to picturing what we see as formative experiences of small hominins slung to caretakers amid the rugged geographies of Plio-Pleistocene East Africa.If rift valleys served as refuges during bouts of rapid climate change, so too, observe King and Bailey (2006), did they function as pathways for successive waves of migrating humans -across and out of Africa.This insight invites closer conversation with Hrdy's (2009a) point that 'cooperative breeding was to permit a hunting and gathering ape to spread more widely and swiftly than any primate ever had before' (p.89) and with our own foregrounding of infant-carrying aids.
If, in one sense, child-carrying slings are vehicles for the spatial traversal of complex, dynamic terrain, Hrdy's account also evokes vehicles of another kind, those that help connect bodies over multiple generations.In a literal sense, we envision slings and related technics of child-mobility as interscalar vehicles, helping hominins both to negotiate the surface of a changeable Earth and binding together a chain of caring bodies across vast, eventful reaches of time (see Clark, 2017).Indeed, we might say that infant-carrying aids help give or generate time itself, at least for our genus, through their contribution to the opening up and sustaining of futurity -perhaps as pressing a challenge in the current geoclimatic juncture as it was during Plio-Pleistocene climatic swings.

Towards a paleogeography of child-carrying
Using a borrowed sling, a contemporary mother experiences the tactile qualities and hands-free affordances of babywearing, without realizing the practice may have barely changed since the ramblings of H. erectus.A 21st century grandmother straps on her grandchild, unaware of the contribution of postmenopausal matrilineal kin to hominin survival during Pleistocene climatic upheaval.A suburban father bundles his baby daughter under his clothing to shelter her from driving snow, perhaps reprising a primordial response to protecting a child from rain, ash or smoke.Each of these contemporary infant caregivers feels a tug of familiarity, although there may be a rupture of many generations in the tradition they are reprising.
To contemporary human geographers, the idea that assumptions of a unilinear and progressively modernizing human trajectory might be thrown off course by the reappearance of ancient practices is unlikely to be especially perturbing.Such complications of here and there, now and then, are familiar contours of relational thought.But the accompanying tone of post-foundationalism, anti-essentialism and the valorisation of plural ontologies tends to discourage taking the originary stories of the paleodisciplines as fertile ground for critical thinking, especially when evolutionary discourses seem to imply that inaccessibly anterior developments set standards for what is admissible in the present.The linking of certain reproductive strategies with evolutionary success in the work of Hrdy and others, we note, has attracted criticism for naturalizing liberal ideologies -by privileging what science studies scholar Donna Haraway (1992) referred to as an 'investing strategic self' (p.350).Hrdy's evolutionary take on the family has likewise been targeted for taking adaptive utility or survival as the measure of humans and other species (Laracy, 2011).Not only does the couplet of infant-carrying technics and cooperative breeding risk essentialising a particular vision of what it means to be human by this logic, but current concerns with decentring 'the anthropos' also prompt us to consider whether the story we have been telling conveys a certain human exceptionalism.These questions need to be taken seriously, we suggest, not just because they highlight risks of this way of thinking, but because addressing such concerns can also accentuate the strengths of an evolutionary and paleogeographic approach to infant mobilities.
It is worth recalling that despite some misgivings, Haraway (1992: 359, 350-351) commended Hrdy's project for the way it emphasized female proactive sexuality and collective agency.But as we touched upon earlier, subsequent work on alloparenting has further unsettled gendered divisions of labour, both by widely redistributing 'mothering' roles and by foregrounding the breadth of activities caregivers can engage in while carrying children.More difficult to work around is the persistence of themes of survival, adaptability and fitness in evolutionary anthropology -or the logic of 'earning descendants'.However awed we might be by the way ancestral humans endured Plio-Pleistocene climatic instability, and whatever anxieties we may have about Earth system upheavals now underway, it is important to consider recent critical work that troubles the centrality of survival and the related intensity of investment in the figure of the child.Alongside literary studies scholar Rebekah Sheldon's (2016) timely interrogation of the trope of reproductive futurity, queer theorists such as Lee Edelman (2004) have posed searching questions about the way that child-enthralled future visions serve to devalue tactics, dispositions and desires that are neither focused on the child nor deferred to some future moment, while geographer Ben Anderson (2022) cautions against prioritizing infant-caregiver bonds in the theorization of attachment.Such critiques have informed our own prioritization of affective, expressive and tactile encounters -and helped us to conceive of both short-and long-term survival less as an end in itself and more as a sometime byproduct of a suite of intimate gestures performed for their own pleasure and satisfaction.
Moreover, while child-carrying practices are the crux of this article, we see no reason why the intercorporeal, empathic and multi-sensual experiences at the core of caring for small humans might not be generalized far beyond infant-caregiver relations.Indeed, this is what the notion 'of our peculiarly "hypersocial"' intersubjective aptitudes points towards (Hrdy, 2005: 87).It also resonates with the idea, prominent in theories of care, that caring relations tend to be set in motion by a fundamental receptivity or opening of the self, and only later -if at all -do they settle into more regulated or calculated sets of exchanges.So too should we recall Hrdy's point that hominin 'big brains' were more likely a collateral effect of shared care and provisioning than a causal factor, a point that we would extend to survival or 'living on' more generally.As Hrdy makes it clear, '(n) atural selection has no way to foresee eventual benefits.Future payoffs cannot be used to explain the initial impetus' (Hrdy, 2009a: 30).
We also note that identifying peculiar or unique characteristics of our own species and genus is not the same thing as advancing human exceptionalism.Whereas much contemporary human geography highlights differences between human groups and shies away from identifying categorical traits of humanness, the cooperative breeding paradigm -along with human evolutionary theory more generally -concerns itself with the specific and definitive features of the extended hominin family.But evolutionary conceptions of the human oblige researchers to take seriously the capabilities, achievements and developmental pathways of other-than-human forms of life -as we have seen in the acknowledgement that cooperative breeding is a strategy that spans multiple biological lineages.A focus on infant-carrying also opens up speculative questions about the possibility of ancestral humans taking cues from the way other species carry their young, together with more accessible evidence of our species making use of their child-carrying devices to convey the young of other, companion or domesticated species.And although we cannot assume any deep, evolutionary resonances, it is worth noting the international outburst of knitting 'pouches' for orphaned, injured and traumatized animals during the 2019-2020 Australian bushfires (Paul, 2020).
Still more important for us is the way that developing the insights of the other paleo-disciplines into a revitalized 'paleogeography' opens relational approaches to the deep temporal transformations of the Earth.Rather than anchoring the arc of human evolution in a stable ground, attention to the dynamism of the early hominin environment offers a reminder that origins tend to be complex, shifting and equivocal, and in the case in question, quite literally rifted.
Baby-carrying slings bring together the security of tactile contact with a raised, outward-facing orientation to the social milieu, an idea we have fused with the claim of cooperative breeding theorists that socially distributed childcare encourages curiosity, confidence and receptivity in our young.Hrdy's (2009a) evidence that 'children who are accustomed to multiple caregivers grew up less likely to fear strangers' (p.134) is one we have sought to extrapolate to the strangeness or selfestranging dynamics of the Earth.As Hrdy herself observes of foraging communities worldwide, and as Indigenous spokespeople have long insisted, this sense of trust and security extends well beyond the immediately 'human' sphere.For all the challenges posed by shifting, changeable milieux, foragers 'tend to share a view of their physical environment as a "giving" place occupied by others who are also liable to be well-disposed and generous' (Hrdy, 2009a: 133).Or as botanist and Potawatomi nation member Robin Wall Kimmerer reminds us, not only does a deeply inscribed sense of the generativity of the living Earth help Indigenous peoples endure episodes of eco-climatic hardship and extremity, it can also offer support in the face of ecological degradation.'Even a wounded world holds us', she reflects, 'giving us moments of wonder and joy' (Kimmerer, 2013: 327).
In this way, we position our thoughts on the technics of infant-carrying within the broader paradox that socio-cognitive attributes deeply inscribed in hominin evolutionary pathways could be a key to flexible responses to human-induced change in Earth systems.Our point is not simply that slings may be useful as post-Holocene physical upheaval impairs the relatively even and regular surfaces that support wheeled vehicles -for some of us, at least -in well-resourced regions.They are also good to think with and through.Baby-wearing technics, we suggest, enabled a combination of tactile security with the ongoing exposure of a receptive, hyper-alert infant primate to the panorama of terra mobilis over million-year timescales.While such devices are unlikely to play more than a supporting role in sociotechnical responses to Earth system change, they are exemplary 'interscalar vehicles' for navigating between the intimacies of human care and the grand challenges of learning to live with post-Holocene planetary instability.It is in this regard that we propose technics of infant mobility as a generative point of entry into a reimagined paleogeography: a field we envision as being hospitable to the disciplines that currently specialize in evolutionary thinking but also attuned to human geography's own potential contribution to the wide-angle storying of our extended hominin family.
By helping fold and stretch our imaginations, baby slings invite us to consider how contemporary socio-spatial questions about 'orienting oneself in three-dimensional space' have deep temporal precursors: antecedents that bring into focus the ongoing geological formation of those spaces.While our deep dive into infant-carrying serves as a reminder that early childhood experience may be crucial for preparing young people to respond flexibly and confidently to the geoclimatic transformations now underway, we have been keen to temper this point with cautionary notes about offloading the burden of planetary salvation onto younger generations.If what a small child encounters as they move through the world is formative, then what matters -at least as much as how they are supported and conveyed -are the activities going on around them.And the activities we would hope they witness ought to already include the wide-ranging, richly-textured, hands-on work of collectively engaging with rapid planetary change.

Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.