Why cities are where they are

DR. RANDY HAAS / COURTESY

Natural resources not the only thing dictating where cities are formed

Cities like New York, Los Angeles and San Francisco presumably grew based on agriculture and geographical resources. New research from UC Davis shows that factors such as migration patterns, economic opportunities and the availability of these resources all impact why cities are where they are.  

Throughout the world, a hierarchy of cities exist in each country, with a large settlement within that country serving as the apex of its society. Today in the United States, New York City is an example of this. Then, you have lower tiers of cities that are much smaller. This pyramid structure is believed to not only exist in modern times, but also in hunter-gatherer societies of the past and present.  

Randy Haas, an archaeologist at UC Davis, travelled to Mongolia in the fall of 2017, along with three of his colleagues, and found another reason as to how these complex societal structures formed.

“My expectation was, as we went back in time, that these hierarchical structures and settlement patterns ought to drop out, but they didn’t,” Haas said.

Cities act like reactors for manufacturing and production, while agricultural settlements tend to disperse people. Haas found that the same statistical pattern holds true for societies who do not have agriculture and cities.

“It’s not just natural resources that are structuring how hunter-gatherers moved through their environments, it’s also the cultural landscape as well — the way hunter-gatherers structured their environments,” Haas said.  

As nomadic people settle from place to place, they leave behind some unit of cultural material — a stone tool, fire hearth, posts of a house, improved landscape and so on. The constant reuse of these landscapes creates economies of scale that Haas saw in his statistical model.

“We move a lot. And when we move, we tend to move where people have been already,” Haas said.

While in Mongolia, Haas found a feedback loop for how many times each site was reoccupied.

“The model worked,” Haas said.  “The only way you could get that hierarchical pattern is through recursive use of landscapes.”

Jelmer Eerkens, a UC Davis alumnus and professor in the Department of Anthropology, also researches hunter-gatherer behavior.  

“Most cities are not strategically placed or planned,” Eerkens said. “There isn’t an easy rule that defines why some locations became large bustling cities and other places were abandoned, or remained small towns.”

Most cities today typically began as a small village where basic resources like water, fertile soil, and trade were plentiful. For example, London had a population of 25,000 in 1200 A.D. and has doubled in size every century. Nearly 8.8 million people live in London today.  

As villages grow into cities, more and more people are attracted to the growing economy and populations grow exponentially. Cities improve commerce, breed markets and even create favorable dating environments. Small businesses lead to greater success by expanding upon previous advancements through trial-and-error.  

“It’s a basic cultural transmission process,” Eerkens said. “As growing cities push the limits of natural resources to sustain them, people come up with solutions.”

These solutions could include increased access to medicine, improved technologies and new engineering developments.

“These ideas build on one another, involve trial-and-error innovation, and involve many cooperating people,” Eerkens said.

People build dams to store water, roads to improve trade and homes to attract people. With these advancements, come newfound problems — war, disease, pollution and so on.  

Humans need to live with other people. As a cooperative species, according to Eerkens, we are dependent on people we don’t even know to spread out the risk of not having enough food, water and shelter.  

“These factors dictate where we live, today and in the past,” Eerkens said.  

The same hierarchy can be traced to places like ancient Mesopotamia, India, Egypt and Peru. Generally, cities are densely populated, and agriculture is less so.  

Haas traveled with the indigenous people of Dukha for six weeks throughout their homeland in northern Mongolia. The Dukha herd reindeer for a living and set up temporary homes each season before deciding to move elsewhere. Haas followed their settlement patterns and shared his findings with the Anthropology Club at UC Davis.

Jenny Chen, a fourth-year biological anthropology and English double major at UC Davis, transferred from UC Merced last year to seek out more internships opportunities in Davis.  She is the treasurer for the Anthropology Club on campus.

Anthropology examines aspects of humanity such as culture, language and stories from our past, with the common theme of answering the question: What makes us human?

“Archaeology instantly captured my attention because people and things that have been preserved for thousands of years can tell us so much that can be helpful for gaining a better understanding of how we as humans come to be today evolutionarily and culturally,” Chen said.

The UC Davis Anthropology Club meets weekly by bringing a variety of guest lecturers ranging from prehistoric arctic fishing to social organizations in the Quechua and Aymara.

“Some of our club members are also not anthropology majors, but just love learning about the nature and culture of what it means to be ‘human,’” Chen said.

Haas gave a talk at the Anthropology Club on campus. Chen was in attendance.

“[The] meeting taught me that technology is constantly giving us more insight and more discoveries about people in general,” Chen said.

In his talk, Haas emphasized that he had the opportunity to live and interact with people in Mongolia to better understand the data he was collecting. Rather than working with data in a lab and on a computer, Haas reiterated the importance of immersion and participation in the field.  

According to Haas, the pyramidal settlement hierarchy is fundamentally embedded in human societies dating back 50,000 years or more.  

“We don’t know if this pattern existed before that, but I suspect at least 10,000 years here in the New World and possibly much earlier among our Paleolithic ancestors in the Old World,” Haas said.  

 

 

Written by: David Madey — science@theaggie.org