CARTA: Comparative Anthropogeny: Technology

CARTA: Comparative Anthropogeny: Technology

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[MUSIC] We are the paradoxical ape, bipedal, naked, large brained, long the master of fire, tools, and language, but still trying to understand ourselves. Aware that death is inevitable, yet filled with optimism. We grow up slowly. We hand down knowledge. We empathize, and deceive.

We shape the future from our shared understanding of the past. Carta brings together experts from diverse disciplines to exchange insights on who we are and how we got here. An exploration made possible by the generosity of humans like you. [MUSIC] Hi. Today I'd like to talk about what makes humans unique. Many people would point to the sophisticated technologies that we have, like this Saturn V rocket that have spread our species around the globe and even carried us into space.

For good or ill humans are now one of the major causal forces acting on Earth's biosphere and technology is the reason. Any serious attempt to understand human evolution must consider our long and formative engagement with technology. First, we need to take a step back and ask exactly what we're talking about here. What is technology anyway? Everyone can agree that things like rockets and computers are examples of technology but what about bodily techniques? Sophisticated meditative practices? What about social engineering? Are these technologies? Are they arts, sciences? What's the difference? Technology has been defined as everything from a set of hardware to a system of abstract rules for problem-solving. For example, language and number systems have been described as cognitive technologies.

BF Skinner envisioned a technology of behavior and Foucault enumerated technologies of production sign systems, social controls, and the self. Potential meanings of technology thus ranged from the smartphone in your pocket to all of human culture and cognition. Since we need to agree on terms here is a conventional social science definition of technology. Technology is an integrated system of hardware, people, skills, knowledge, social relations and institutions applied to practical tasks. I think this captures a lot of what is interesting and distinctive about human technology, but it leaves the critical question of what exactly constitutes a practical task undefined. They were essentially asking us to make a subjective and valuating judgment about what qualifies as practical.

For current purposes, I'd like to make this definition a little more precise by grounding in an evolutionary theory and particularly the way in which technology and biology have co-evolved to shape human minds, bodies, and environments. Humans inhabited technological niche that we ourselves have constructed. Take this scene from the famous Shibuya Crossing in Tokyo. Arguably, there's not a single natural thing in sight.

Even the bodies of these people have been transformed by our long history of reliance on technology. From reduction of the jaws and teeth and guts through external processing of food to our manipulative hands and arms and the large energy-hungry brain. The other thing I want you to notice is how many people there are. Human children with their big fancy brains take longer to mature and much more parental support than any other ape.

Yet, there are more than seven billion of us, and precious few of them. Paradoxically, human women have the shortest inter-birth interval and the highest total fertility of all the apes. Simply put, human mothers should not be able to afford this rate of reproduction. The reason they can is because they receive support from others: fathers, grandparents, siblings, other members of the community, and so on in what has been termed the human biocultural reproductive strategy. For this to be possible, these others must be producing more than the bare minimum needed to support themselves.

Chimpanzees basically don't do this. They have a production and consumption that basically track each other with very little difference throughout their lifespan. Humans, on the other hand, have a very long, costly childhood in which we consume a lot more than we produce, but eventually, we do learn to produce a real surplus. This is enabled by culturally accumulated knowledge and skills for material production.

In other words, what I would call technology. This can lead to a powerful biocultural feedback cycle, where technology increases production, which enables sharing, which supports extended development, long lifespans, and population growth, which allows in turn for a large brain and heavy learning investments which enable further technological elaboration and so on. This feedback cycle has produced a human-constructed technological niche, populated with increasingly complex systems for material production. This evolutionary grounding finally allows us to be a bit more specific about what we mean by practical tasks. What I'm proposing is that technological systems are practical in the very concrete sense that they support the material production underwriting our species' entire biocultural reproductive strategy.

This evolutionary framing allows us to focus on key features of technological systems, including the fact that they are socially reproduced, deeply collaborative, and they concern material goals to enact physical changes in our environment. The key distinction I'm making here is between materially instrumental tasks that are intended to achieve physical changes in the world and communicative tasks that seek to alter the thoughts, behaviors, or experiences of the self and others. Human culture clearly encompasses both of these kinds of goals, but technology is here defined by its focus on the material goals, materially instrumental goals. In this sense, there could be technologies for the production of communication tools, such as books, musical instruments, or computer networks, but there would be no technologies for effective storytelling or musical composition or rhetoric or social messaging.

Systematic approaches in these communicative demands might better be termed arts or sciences rather than technologies. But that's not our focus here. This distinction may seem semantic, but it's important because material and communicative goals tend to have very different functional demands and design constraints. Material goals are shaped by physical situations and materials which may be relatively invariant across time and space.

Communicative goals, on the other hand, must address human psychology in the context of specific cultural systems of meaning. They will thus tend to implicate different cognitive processes, learning strategies, and cultural evolutionary dynamics. All of this finally places us in a position to ask the core question, well, what is it that makes human technology possible? We could argue about whether non-human tool use qualifies as technology or not, but clearly there is a massive difference in magnitude between the termiting one here and the cell phone that it's being displayed on and this requires some kind of explanation. Currently, the most popular explanation is that human technology is made possible by our uniquely evolved capacity to learn from each other.

High fidelity social transmission drives a lossless ratchet effect, where each generation adds to the product of the last until we have complex technologies vastly beyond any one individual's creative ability. This compelling concept of human cumulative culture is illustrated by a thought experiment known as the Island test. Imagine you grew up alone on this island and survive somehow.

What would you be able to re-invent on your own in a single lifetime? Probably most of us could manage some chimpanzee tools like a termiting stick, but not something like a cell phone, which clearly requires generations of accumulated knowledge. The argument then goes, it is this high-fidelity social learning that is the key difference that made human technology possible. I don't think that is enough. Let's imagine that you also have a phone on this island that you can not only copy this phone, but you can use it to call the world's experts and cell phone technology, lookup plans, instructions, and whatever you like. Now, would you be able to make another phone? I still don't think so because technological production is about more than just information, it requires materials, infrastructure, social institutions, trade networks, and so on. There's a lot of complexity in technology.

The point is that there's probably no one thing that makes human technology possible in general. Rather, humans display a wide variety of different technologies with different demands for different kinds of cognitive and motor skills, different forms of social and individual learning, different material and social infrastructure, and so on. Nevertheless, I'd like to suggest that some synthesis is possible. By focusing on the three unifying technological characteristics I outlined earlier being material production, social collaboration, and cultural reproduction. For example, the materiality of technology allows for the accumulation of complexity beyond what any one person could hold in their head and provides a durable medium for collaboration across time and space.

Technological materials embody information and persist across generations as a new form of cultural inheritance. Durable artifacts in situations like this blacksmith's workshop are environmental resources that scaffold cognition by externalizing the information representation and manipulation. This enables the evolution of complex technological goals and extended action sequences beyond the planning and memory capacities of individuals. This critical material amplification in turn depends upon exceptional human capacities for skilled interaction with the physical world. Cognitively, this skill interaction is supported by internal models of the world that can be used to simulate and predict the action outcomes. This allows for smooth anticipatory control and action planning.

Normally you don't notice this kind of thing. But just imagine how it feels when you reach out to pick up a container of say, a tea kettle, and you think it's going to be full of water and heavy, and you get ready to do that and you jerk up uncontrollably when you find that your internal model is actually inaccurate and you need to revise your understanding of the world you're operating. This physics engine in the brain is particularly well-developed in humans compared to other primates. It is thought to play a parallel role not only in planning and executing actions, but in understanding the observed actions of others in a way that allows imitative learning. This capacity to simulate, understand, and imitate observed actions may also be important for technological collaboration. Unlike simple tool use, technology is often characterized by the coordinated action of many individuals over extended periods of time.

Such collaborations is especially obvious in the specialized roles, logistical chains, equipment and infrastructure characteristic of modern technologies, but it's critical even in much more ancient technologies. At a basic level, the coordination of action between individuals is thought to rely on reciprocal prediction achieved by the very same internal models for anticipatory motor control that I just discussed. Such interactive synchrony is sometimes also called brain-to-brain coupling, can occur at multiple levels of abstraction and provides a key mechanism supporting the development of mentalizing, empathy, communication, learning, and social affiliation. These are in turn critical to supporting technological collaboration at larger group and institutional scales. For example, effective teamwork is facilitated by emergent group properties including shared mental models, effective states, with behavioral and emotional alignment, promoting the self identification with social groups that motivates norm adherence and allows assembly of larger technological systems.

Finally, there is the reproduction of technology. This is really a special case of collaboration and dependent on many of the same mechanisms. Although social learning is commonly gotten lost as the transmission or copying of information, technological learning is often a protracted collaborative process better described as the reproduction of skill. The learning demands of different technologies will then depend on the particular skills involved. For example, this is a picture from a longitudinal study of stone toolmaking skill acquisition that we conducted in my lab. We found that although there are some basic concepts to master, these concepts are pretty intuitive.

The real challenge as it turns out is to develop the internal models and perceptual motor precision to actually hit what you're aiming for with the right amount of force. This can take hundreds and hundreds of hours of practice, and the role of the instructor is really more to provide the materials, situations, opportunities, and encouragement for practice rather than to directly communicate didactic information. Now, this might well be different in other technologies that are more dependent on conceptual and symbolic skills. However, it does remain to be seen whether the processes of cognitive and perceptual motor skill learning are really as different as we think. In any case, it's clear that the conventional distinction between social and individual learning and comparative psychology and cultural evolution, is difficult to maintain in the case of technology. In fact, these kinds of learning rely on similar neurocognitive mechanisms and are thoroughly intertwined throughout the learning process.

This is exemplified by technological apprenticeship, which alternates social learning with individual practice in an iterative process of increasing refined. Social information ranging from artifacts, tools, and observable behaviors to intentional demonstration, feedback, and explicit instruction from teachers guides learners to recreate increasingly sophisticated skills through deliberate practice over extended periods of time with each round of individual practicing allowing deeper appreciation of the available social information and so on. All of this complexity and variety means that we probably should not be looking for one simple explanation or a threshold moment that set humans on an inevitable path to ever more complex cumulative technology. Rather than a major evolutionary transition, we should be considering the complex and historical contingent processes by which the evolution of particular technologies occurred. This would retain the existing attention to social learning mechanism while expanding the scope of inquiry to consider the broader technological niche of ecological material and social arrangements, as well as interactions between technologies.

For example, it's widely thought that there's some kind of problem, something curlier about the longevity of Paleolithic technologies like this Acheulean hand ax. These consistent forms seem to suggest the high fidelity social transmission that is proposed to lead to runaway cumulative culture, and yet they don't change for millions of years. For the social learning hypothesis, this apparent paradox means that we must be wrong about these tools. Maybe they're actually easy to learn with ape-like social transmission mechanisms. Or perhaps our ancestors were actually genetically programmed to make them and they're not social at all. Both of these solutions have been proposed.

But what if hand axes were just the best solution for the lives our ancestors were living. Technology is about more than just information, and technological choices come with costs as well as benefits. Actually, a hand ax is about as good as you can get for a stone cutting tool until you add a handle.

Is it really worth adding all that wood harvesting, sinew binding, glue making, and so onto your life? Maybe not until something else changes the equation. The point is that technological feedback can occur, but we have no reason to assume they will always occur or be indefinitely self-sustaining when it does. That will depend on a wide variety of particular conditions that may or may not apply. From this perspective, we might equally ask why our modern technological systems are so radically unstable, as why things change so slowly in the Paleolithic. It's not clear that the answer to such questions will always be something to do with social learning mechanisms.

I've painted a picture of technology is an enormously complex phenomenon, and spanning a scale from molecules to societies and beyond. How are we to deal with all of this? I'm not really sure, but I'd like to think that the vast scope isn't just a problem, it's also part of the solution. That's because interaction between multiple levels of spatiotemporal organization is a key feature of evolutionary thinking, and it allows synthesis of complex phenomenon in terms of a smaller number of recurring relationships and processes. For example, I have stressed the importance of internal models for everything, from motor planning to the development of theory of mind in the formation of social institutions. This has led us to suggest a perceptual motor hypothesis for the construction of human technological cognition from ancient primate perceptual motor systems for body awareness and engagement with the world. According to the perceptual motor hypothesis, sensorimotor acuity and experience shape the construction of internal models and intuitive physics required for material production.

In turn, sensory predictions by these models support the sense of agency and self other discrimination that underpin humans self-awareness, imitation, social cognition, and empathy. The social cognitive capacities enable technological collaboration and reproduction, and thus create possibilities for further bio-cultural evolutionary feedback. In fact, the frontal parietal systems that support action execution, observation, and intuitive visible reasoning have undergone major structural and functional changes over human evolution.

These systems are also relatively early developing in the life-force, and directly engaged with the sensory periphery, which makes them the key nexus for interaction between externalizing processes of technological niche construction, and internalizing processes of neurocognitive development. I don't know if the perceptual motor hypothesis is on the right track or not, but it does at least make testable predictions. For example, we would expect basic perceptual motor variation to be associated with otherwise unexpected variation in processes of technological production, reproduction, and collaboration.

But this is just one example of the kind of hypothesis that could be addressed by an integrated cognitive science of technology. I have argued that there is no single cognitive behavioral or social essence that defines human technology. The proper study of technology is going to need to be inherently multi-disciplinary and require a comparative approach to identify pattern relationships between contexts, mechanisms, and functions across technologies.

We all need to embrace this complexity rather than attempting to generalize from a small number of ethnographic examples or experimental manipulations. Finally, the scale of technology is going to further require long-term study embracing a variety of qualitative and quantitative methods, including emerging methods for real-world neuroscience, wearable devices, ecological momentary assessment in digital phenotyping. Clearly we have our work cut out for us in studying technology, but I'm excited by the prospects. Thank you very much. [MUSIC]

2021-11-04 15:39

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