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  • Writer's pictureCatherine Oliver

Eating Chickens, Consuming Cities: Urban Metabolism in Animal Studies

Updated: Jan 11, 2022

In Spring 2021, I was delighted to join Claudia in Season 3 for an episode of The Animal Turn focused “urban metabolism”. In this blog entry, I expand on some of the ideas we discussed in the episode around what urban metabolism is, and how it has been defined in different ways. I explore some of the ways that urban metabolism has opened interesting ways for me to think about animals that are usually eaten by humans, as well as the food that these animals eat. I am particularly interested in how eating and metabolising can construct urban space in different ways.

In the latter half of this blog, I draw on my own research with urban chickens in London. I consider how London’s galline life has transformed over the past 150 years, effectively seeing chickens disappear from the city after the Victorian era, entering only as pre-packaged food to sustain the urban (human) population. However, there has recently been a resurgence of chickens in London and other cities, as people have begun to bring chickens into the city as pet-producers. Urban metabolism can help animal studies scholars to understand more-than-human urban relationships and spaces, and in turn scholars might consider taking up urban metabolism theory to consider the city differently from these animals’ perspectives.

What is “urban metabolism”?

Most humans will live in cities by 2050, around 70%, and megacities are also on the rise (Dijst et al 2018). Cities consume more materials and generate more waste; they generate huge amounts of “wealth” and home billions of people. Cities are flows, processes, systems, of which urban metabolism is one construction trying to map and understand them. From an urban metabolic perspective, spatial and economic processes, as well the social, cultural, and political life of the city are mapped alongside natural processes of climate change, water flow, air make-up, erosion, and nutrient flows. Urban metabolism is part of many disciplines and is being tested as an interdisciplinary concept through which we might understand how to make cities more sustainable, healthy, and thriving places for humanity and for non-human animals and plant life as well.

In Three Ecologies (2012), David Wachsmuth traces an intellectual history of the concept. He begins by explaining that the idea of metabolism was coined in the 19th Century to describe chemical changes in living cells, before being taken up by biology and biochemistry to characterise organic breakdown in individual organisms. The idea of an urban metabolism is split into three ‘ecologies,’:

  1. The first emerging with the Chicago School in the 1960s, ‘who treated the city as an ecosystem in analogy to external, natural ecosystems, and conceptualized urban metabolism as a process of social change internal to the city.’

  2. The second is the era of industrial metabolism, material-flows analyses of the city, adding external elements such as raw nature into the equation (see also Hannah Landecker, Postindustrial Metabolism, 2013), in a technocratic idea of the city.

  3. Finally, urban political ecology emerged as a hybrid approach to metabolism, based on the dissolution of the society/nature dualism, where the city is a product of diverse socio-natural flows.

Wolman, 1965, The Metabolism of Cities, p.185 © Scientific American Inc 1965

The “metabolism” of a city includes all the fuel, materials, commodities to sustain the city’s inhabitants at work, leisure, and play, across time, including the construction and expansion of the city (Abel Wolman, The Metabolism of Cities, 1965), as well as the waste that the city and its inhabitants produce. The Earth is a closed ecological system (although where the boundaries of that system are can expand into space, see Elizaeth Kolbert, Under a White Sky, 2021, as capitalism breaches new frontiers, see Jason Moore, Capitalism in the Web of Life, 2015), and both the materials and the waste of the city have to come from somewhere. Urban political ecologists such as Erik Swyngedouw, Nik Heynen, and Maria Kaika (In the Nature of Cities, 2006) have conceptualised this somewhere as the city’s hinterlands. As such, for them, it follows that everywhere is implicated in the urban and the urban is, through material transformations, also nature. The urban is thus not a bounded space but, as urban metabolism theory contends, connected beyond the city limits. In the urban metabolism system, there are endless exchanges and flows intra- and internationally, drawing us towards thinking about the city as an already more-than-human system of flows, processes, and interconnectivity.

Metabolism is always more-than-human, but to closely comprehend how this might matter to animal studies, we need to consider the two kinds of metabolism (one related to Marxist relations of nature and the second to postindustrial processes) that are being discussed, and what the reconciliation of these two metabolisms allows us to think about in relation to (urban) animals.


Reconciling metabolisms

There are, as I alluded to in the first part of this blog, two forms of thinking about metabolism that are pertinent to understanding and theorising from an urban metabolism perspective with animals. The first of these is related to questions of Marxist relations to nature, most notably written about by Jason W Moore, building on and furthering the ideas of John Bellamy Foster. The second is of metabolism as a chemical, physiological, biological process of the body, and how this has changed postindustrialisation, writing ideology into bodies at the scale of the cell, drawing particularly on the work of Hannah Landecker. In this section, I write about these two metabolisms, and how they might matter to animal studies through eating and porosity.

Marxist metabolism

In his 1999 paper Marx’s Theory of Metabolic Rift, John Bellamy Foster took up and challenged the, at that time widespread, idea that Marxism and environmentalism were at odds in sociological theory. He argues that Marx’s theory of a metabolic rift between human production and the earth’s natural conditions has important classical foundations for environmental sociology. On the contrary, Bellamy Foster contends, Marx ‘went a considerable way toward a historical-environmental-materialism that took into account the coevolution of nature and human society’ (p.373), especially attending to agricultural industrialisation. Marx used the concept of metabolic rift to ‘capture the material estrangement of human beings in capitalist society from the natural conditions of their existence. To argue that large-scale capitalist agriculture created such a metabolic rift between human beings and the soil was to argue that basic conditions of sustainability had been violated’ (p.383).

In his 2017 paper, Metabolic Rift or Metabolic Shift?, Jason Moore builds on Bellamy Foster’s arguments and develops them further in understanding capital, nature, and crisis. Moore argues that metabolic “rift” arguments pivot on environmentalist tropes of separation: that human and nature are somehow disconnected. Moore argues instead that Marx was concerned with movement and relationality in his metabolic theory. The metabolic rift is historically constructed through environment making by human and extra-human natures, and, crucially for Moore, Bellamy Foster ignored geographers, for whom society/nature and human/environment questions is embedded in our disciplinary canon. Moore does agree with Foster on the key point that ‘human organizations unfold with a biosphere that shapes human sociality and is shaped by it’ (2017, p.312) but goes further to say ‘metabolisms are always geographical. Capitalist relations move through, not upon, space, which is to say through, and not upon, nature as a whole’ (p.313).

Postindustrial metabolism

The second kind of metabolism that we can bring into dialogue with urban animal studies is that of a biological, biophysical metabolism. For Hannah Landecker (Postindustrial Metabolism, 2013), the development of metabolic knowledge in nutritional science in the 19th century is tangibly connected with the industrial era, being focussed on the conversion of matter from raw materials of nature to products of man. In the industrial era, Landecker argues, biological ‘metabolism was understood as a factor, a “singular inward laboratory.”’ In this conceptualisation and early understanding of metabolism, when food is consumed, this is followed by biophysical processes to break down the food, nutrients are taken in and any excess becomes waste through excretion. This fit with wider ideas of the body as a factory in the 20th Century, following a Cartesian mind/body dualism, which ‘changed the paradigm of metabolism to one of the interconnected biochemical pathways located deep inside the body, in cells and organs connected through flows of blood and other fluids’ (Anita Hardon and Carolyn Smith-Morris, Reconfiguring Metabolism, 2019).

The postindustrial era has, however, seen a shift to what Landecker (2013, Postindustrial Metabolism) to a “new metabolism,” based on advanced nutritional understandings. A postindustrial metabolism is no longer conceptualised as a factory but rather as a “regulatory zone.” Contemporary metabolic knowledge is ‘a dynamic web of cellular signals, built by and responding to environmental information—food molecules or food pollutants’ (p.496). Knowledge of metabolism in the postindustrial era is through environmental risk, management, and information, encapsulated in the systems of signals and stores of metabolism being entangled with different temporalities and larger environments beyond the body. No longer is metabolism a question of what goes in, and what comes out, but can only be understood within wider conditioning environments.

The “new metabolism” approaches food as being broken up, stored, attaching to fats or lipids, and sometimes doesn’t move through the system in a linear fashion. Metabolic crises, such as so-called obesity epidemics (see Lee Monaghan, Rachel Colls, and Bethan Evans, Obesity discourse and fat politics, 2013 for a critique of this moral panic) have thus become regulatory problems. As such, metabolism is not simply a biophysical system, but is also writ large with social, cultural, and political ideology. Metabolism is thus related to changing frames of scientific advancement, but also as metaphor. Metabolism is working as a conduit between economic and biological domains, revealing. the porosity of science and its cultural context. ‘Metabolism is not a concept floating above time … More than a shift from one theory to another that could be described as a history of metabolism, metabolism is in history: the material of the bodies fed by an industrialized agriculture and food-processing systems’ (Hannah Landecker, Postindustrial Metabolism, p.497).


Porosity, metabolism, and animals

Metabolism has thus become porous, much as Anne Marie Mol proposed of eating in her essay I eat an apple (2008), which is a meditation on eating and subjectivity. In the essay, Mol talks about Granny Smith apples: “I don’t like Granny Smiths. In the late 1970s and early 1980s we (my political friends and myself) invested a lot in disliking Granny Smiths. At the time they were always imported from Chile, and thus stained with the blood spilled by Pinochet and his men.”

Mol’s essay goes on to talk about how when we eat, we become aware of how our body is not under our control – it acts independently of “us,” but it is still “us.” What we eat – what we metabolise – becomes us. The stomach, metabolism, eating is the site of violence, or freedom: it is a political space, but one that is also totally mundane and essential.

For animal scholars, this opens interesting ways to think about the ways that we eat animals, as well as what animals eat. Marxist metabolic rift is concerned with the relationship between humans and nature, and postindustrial metabolism is concerned with what humans eat and how we use and store that as nutrition. Bringing animals and their metabolism into this frame shifts how we can think about metabolism. Indeed, in an essay that I wrote with Jonny Turnbull, A Conduit for Value (2021), we trace a history of nutritional knowledge development for humans as based on experiments with chicken metabolisms. Through the tweaking of chickens’ diets, nutritional scientists have been able to change the vitamin contents of eggs, thus improving human diets. When the egg is used as a conduit for refining human nutritional intake, the chicken body becomes a space (and process) through which desirable nutrients are delivered into human food. Chicken metabolisms have been fine-tuned to synthesise nutritional value for humans, their environments becoming enclosures in the industrial farm, traversing ideas of Marxist metabolic rift or shift, and postindustrial metabolisms. In thinking about metabolism with the commercial egg-laying chicken, we attend to new perspectives on these metabolic theories.

Row of chickens in battery cages at an industrial egg farm.

Image © Jo-Anne McArthur/We Animals, 2019.

Galline urban metabolisms in London

At the turn of the 20th century, more was known about the chicken’s metabolism than any other animal, including humans. The chickens’ body is literally shaped and moulded by capitalist ideology, by industrial knowledges of the factory (Ruth Harrison, Animal Machines, 1964), and by colonialist expansion politics (Andrew Lawler, How the Chicken Crossed the World, 2016). Bigger birds, bigger eggs, more nutritional value: the chicken has become a conduit for bigger, better, cheaper food. These birds aren’t farmed, they are manufactured. The postindustrial metabolism sees birds grow fast and big – squashing profits from farmers, and into corporations. This is entangled with the postindustrial appetite for flesh – the chicken’s popularity as a meat has skyrocketed (see Chris Otter, Diet for a Large Planet, 2020). Where, pre-1990’s, most farmed chickens globally were for eggs, they are now vastly outnumbered by broiler birds. There’s are almost 26 billion chickens alive at any point on earth. What we eat is entangled with how we live, and where we live, connecting back to an increasingly urban world. To understand the contemporary city of London’s urban metabolism through galline life, as I am aiming to do through my research with the Urban Ecologies project, we must turn our attention on the city further back.

One hundred and fifty years ago, at the turn of the 20th Century, London was filled with chickens. This was at the height of hen fever, which was a period that saw a huge surge in domestic hen keeping of rare and exotic chickens, but also of normal egg laying hens across the UK and, soon after, the USA. Queen Victoria and Prince Albert had taken a liking to exotic chicken keeping. Albert had built or refurbished the aviary at Windsor Castle and people from across the world were sending the Queen their hens. Victorian England maintained a menagerie of animals, both exotic and domestic. Elephants, tigers, lions and hippopotamuses were regular captives in the circus, and cities themselves still had free roaming cattle, pigs, and sheep, whilst chickens were homed in backyards.

Windsor Home Park: the Aviary and Poultry Farm dated 1845 © The Royal Collection Trust

London was home to the world’s largest livestock trade and, as Tom Almeroth Williams writes to introduce his book CITY OF BEASTS: ‘No other city in Europe or North America has ever accommodated so many large four-legged animals or felt their influence so profoundly.’ The Victorian middle classes were breeding and exchanging exotic – and expensive – chickens, valuing their beauty over their meat or eggs. When this middle-class bubble burst in the mid-1850s, chickens’ beauty quickly became worthless, ushering in chicken and eggs as a cheap food source. At the same time as “hen fever” gripped the middle classes, eating chickens was a rarity for the poor urban masses. While chickens were kept widely, it was primarily for eggs. Rural farm labourers had access to cheap dairy, vegetables, and animal meat, but urban workers had little to eat, despite the demands of manual labour and the workhouse.

At the turn of the twentieth century, London’s urban barnyard was about to change. In the nineteenth century, Britain was the ‘dominant world power, controlling immense global resources, and creating long-distance supply chains of food’ (Chris Otter, Diet for a Large Planet, 2020).

A “Western diet” rich in animals, processed grains, and sugar related to ideas of power, but it also relied on using the entire planet as a resource.

In the seventeenth century, the English had practiced “internal outsourcing” of food production, using Scotland and Ireland as agrarian resources. Between 1820 and 1914, European food production expanded through colonialism; Britain particularly relied on India, New Zealand, Australia, Argentina, and Uruguay, the latter three of which containing over 185 million hectares of arable land by 1910. Producing cheap food was essential to British and European wealth, and the whole world became their hinterlands. This “nutrition transformation” saw animal products increase, and prices drop. It also saw the sanitisation of cities, as livestock animals were no longer kept or killed on the streets of London. With it, chickens (and other animals) disappeared from the urban fabric, but were present in cages and factories in greater numbers than ever before, as chicken consumption escalated in the twentieth century and continues to rise today (see Karen Davis, Prisoned Chickens, Poisoned Eggs, 1996).

Contemporary London does not have chickens, cattle or sheep roaming the streets. In fact, the way chickens most commonly enter this city – and its metabolism – is as pre-killed and pre-packaged bodies, sold as food.

Whether shrink-wrapped bodies in supermarkets, macerated in chicken nuggets, or the labour of chickens in their eggs, chickens are absent presences in the city.

Chicken is cheap. And chicken is cheap because of the pressure on farmers to make chickens cheap: farmers aren’t sitting on piles of money; they have been totally squeezed out by big corporations and supermarkets demanding ever cheaper prices. This has had a direct effect on the welfare and metabolic pressure on chickens. Urban labour is running on the chickens that humans eat. So is urban play and leisure. But chickens themselves had all but been removed from the city.

Rehomed ex-commerical hens © Catherine Oliver, 2017

Over the last twenty years or so, things have started to change again for chickens in London. The urban backyard chicken-keeping movement has taken off in both the UK and many parts of the US. This has been linked to environmental, ethical, and justice ideas, and ideas of food provenance, localism, and pursuit of ‘the good life’ (which I recently wrote about in Animal Studies Journal). There are, probably, tens of thousands of chickens now living in the Greater London Area in backyards, gardens, and urban smallholdings. Some of these are rehomed ex-commercial hens, and some are pure breed hens bred across Europe and imported into London chicken sellers.


The metabolic city

Metabolism is a plural concept, referring to socio-ecological flows of materials and energy from cells to cities. Scholarship on urban metabolism leverages the concept to attend to the circulatory dynamics of cities, its relations to the countryside, and even a world ecology of capitalism. Metabolic processes in the body – from fatigue to absorption – are being invoked to understand everyday life and to rework the both the body and the city as sites of regulation and control. When we introduce farmed animals to this, these ideas can be expanded even further, as I have explored with hens in the latter half of this blog. So, how might we attend to urban metabolism as more-than-human across these scales?

And what might an ethnographic attention to nonhuman bodies – including on what the animals we eat, eat – offer up for a different reading of the pulse and politics of urban life?

When we think of cities, we don’t immediately think of the nonhuman and animal life literally surrounding us. In fact, I imagine lots of people barely notice urban animal life at all. Geographers have, however, been paying attention to urban animal life for some time now. As Jennifer Wolch wrote about the ‘anima urbis – the breath, life, soul and spirit of the city – [being] embodied in its animal as well as human life forms’ (2002, Anima Urbis, p.721). More recently, Ash Amin and Nigel Thrift have written about the ways cities ‘rely on organized forms of cruelty to nonhumans in order to maintain their human momentum: cities are hungry predators on other forms of life … cities have nearly always been built on the cries and screams and howls of dying animals’ (Seeing Like a City, 2017). It might seem, then, that cities have destroyed urban life but, in fact, this is not the case for all individuals or species of animals; for some, the urban remains a fertile feeding ground – a metabolic space, opportunity, and process.

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