Has the great urbanisation of our species over the last 5,000 years been good for humanity or bad? It’s a story that can be told by examining ancient skeletons – which reveal incredible dangers, but also point to a bright future

The UN human settlements programme predicts that homo sapiens will soon be a majority urban species: 60% of humans will live in cities by 2030. More than 10 millennia of adaptations have gone into changing our lives from free-range to metropolitan. Yet in evolutionary terms this is a blindingly swift change of habitat, and to understand what it means for our future we must turn to the long view of archaeology.

The accumulation of humans in dense habitations – cities – has had enormous and frequently fatal consequences. Problems of access to resources, disease transmission and pollution follow rapidly on the heels of our great urban experiment. And it is precisely these problems, originating many thousand of years ago, that we must come to terms with if we are going to survive as a species.



Skull 1. Violence

Facebook Twitter Pinterest A skull dating back 10,000 years showing evidence of a crushing blow to the forehead. Photograph: Marta Mirazon Lahr

There is unrelenting archaeological evidence that people can be, well, terrible. The “peaceful” Neolithic farming communities of what is now Austria and Germany had a nasty habit of turning up in mass graves, tortured and massacred. These were victims of a world without cities. In the skull pictured here, we can see clearly how lethal violence leaves a testimony in bone: a fatal, crushing blow to the forehead.

The skull of this woman from 10,000 years ago, 5,000 years before the first cities came about, is fractured and dented not by time but by malevolence. Her entire community was wiped out in a violent massacre at Nataruk, near the shores of Lake Turkana in Kenya. Given our species’ long history of violence, it is surprising that there are not more skulls with deadly blows found from times before cities.

Indeed, a recent paper in the science journal Nature has suggested that in the Americas and Europe, the first effects of cities was to decrease the level of lethal violence. This might be explained through the social regulation of violence, as societies had to adapt to closer quarters. Cities may have codified the ways we kill, forcing cooperation, suppressing some of our most violent instincts in order to maintain the hierarchical structures that allow so many humans to live together.

Skull 2. Disease

Facebook Twitter Pinterest The skull of a prostitute with syphilis. Photograph: Linda Nylind/The Guardian

A second skull tells another urban story, in the grim visage of young woman who was buried in the Crossbones graveyard in Southwark, London, a cemetery reserved for paupers and “single” women (or prostitutes) just to the west of what is now London Bridge station. The skull shows all the hallmarks of infection by treponema pallidum – syphilis, the venereal disease that terrorised Europe from the 15th century until the invention of antibiotics.

The infected soft tissue of the nose and mouth have eaten away at the underlying bone, and the cranium is riddled with infection response to the point that it resembles nothing so much as chewed-up gum, hardened over what remains of the skull. This is the face of third-stage syphilis infection; the bacteria will have caused huge lesions and sores all over the body and eventually worked itself into the bone.

Syphilis is a resolutely urban disease. It’s not that it couldn’t infect people outside cities – promiscuity knows no city limits. It’s that you need a lot of people mixing and moving around in order to create the epidemic that swept early modern Europe, and it takes a network of connected cities to move so many people. The reason that over half of the 18th-century medical advertisements stored in the Wellcome Library are for syphilis cures is due not to the promiscuity of people, but of cities.

These first global cities, like their modern counterparts, ran on trade, on exchange, on the movement of people and accumulation of goods. The sudden appearance of syphilis followed the rapacious exploration of new corners of the globe to seek out new sources of wealth, with the urban states of the medieval period vying for resources. Syphilis arrived in Europe in the pockets of acquisitive explorers and spread rapidly alongside the vital flow of trade on roads laid between urban centres and in armies contesting them, to the urban hearts of the late medieval world.

Skull 3. Work

Facebook Twitter Pinterest A skull with phosphorus poisoning in the jaw, the result of 19th-century employment in a match factory. Photograph: Wellcome Library, London

While we might complain today about the cricks in our neck from hunching over screens, the cities of the Industrial Revolution were potentially fatal places to make a living. Hub of production and enterprise, the industrial city has a history of being unkind to its workers; particularly so when the economy is tilted to continually draw in expendable labour. The workers of early modern London faced deadly conditions to keep the wheels of commerce and industry turning.

One of the most shocking examples comes from the phosphorous match factories. Phosphorous is poisonous, but it burns brightly and well, and in the 19th century matches were made by dipping the heads in white phosphorous. A match worker would be exposed to the noxious fumes as they dipped the matchsticks, and the phosphorous would slowly be absorbed into the soft tissue of their mouths. From there, the poison would spread, necrotising the bone and eventually causing the destruction of the jaw, as can be seen in the image here.

The work was clearly dangerous, but the inequality of the economy ensured there would always be new matchworkers. Until, eventually, the match workers decided they had had enough of the exploitative practices that fuelled London’s prosperous few.

Annie Besant wrote a crusading article in 1888, accusing the matchmakers Bryant & May of “slavery”, detailing the horrific working conditions of London’s desperate (and largely female and poor) match workers. The factory owners retaliated by sacking them, and the resulting furore led to a remarkable strike by the women that made waves all the way up to the halls of Westminster. By 1910, parliament had banned the use of white phosphorus.

Skull 4. A bright future?

Facebook Twitter Pinterest The preserved skull of urban reformer Jeremy Bentham, held at UCL. Photograph: UCL Special Collections

The story of humans in cities is one of adaptation. In inventing urban life, we have essentially given ourselves the tools we need to meet our own challenges. Hidden in each of these skulls is a note of optimism.

While violence still haunts us, the fatal pattern of raids and massacres that seem to have been prevalent in the past now occurs mostly where urban states have failed. The diseases that decimated us in the past are now treated with the skills and knowledge born of the specialists and institutions that cities support. And it is among the citizens of our urban centres that we find the movements at the forefront of making the city a safer, cleaner, more equal place.

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A final skull illustrates exactly this best hope for our urban future. In 1832, the pioneering social theorist Jeremy Bentham passed away, and, according to the terms of his will, his body was given over for dissection and eventual preservation in a cabinet located in the cloisters of University College London, while his head was mummified as an “auto-icon”.

Bentham had been part of a wave of philosophers and reformers who imagined a better world geared towards “the greatest happiness of the greatest number that is the measure of right and wrong”. London, the busiest metropolis in the western world, had produced people with a zeal for reform; the legacy of these reforms can be seen in the institutions that harness the city for innovation, for radical thinking and for addressing the very problems our cities throw up. Bentham’s skull is evidence of the track our urban lives left deliberately behind – a reminder that the city, the very engine of so many modern problems, might be the very same adaptive tool that we use to save ourselves.

Brenna Hassett is an archaeologist. Her book Built on Bones: 15,000 Years of Urban Life and Death is published on 23 February by Bloomsbury.



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