Are cities like organisms?

Summary

This video explores the intriguing comparisons between cities and organisms, investigating how both grow, adapt, and utilize resources. While scaling laws for cities mirror those in biology, such as efficiency improvements as cities grow, the metaphor isn't perfect. Cities don’t circulate like organisms, as their street networks are decentralized. The video contrasts cities with other metaphors, like machines or crystals, and emphasizes the importance of these comparisons for urban planning, especially in the context of sustainability and design. Ultimately, the video highlights how cities remain complex entities that defy a single metaphor.

Takeaways

• 😀 Cities share similarities with organisms, such as growth, energy consumption, nutrient distribution, and waste production.
• 😀 Biologists have identified scaling laws in nature, like metabolic rate, that help explain how organisms of different sizes operate similarly.
• 😀 The scaling law for metabolic rate shows that regardless of size, all mammals’ hearts beat the same total number of times in their lifetimes.
• 😀 Cities also have scaling laws, such as the law of economy of scale, meaning that as cities grow, they become more efficient in using resources.
• 😀 Larger cities need fewer resources for infrastructure (like gas stations, roads, pipes) due to economies of scale.
• 😀 As cities grow, they become more economically productive, with higher wages, GDP, and patents, but this happens at a faster rate than just population increase.
• 😀 The negative side is that larger cities also experience higher rates of crime and disease, scaling at a rate of 1.15 for every population increase.
• 😀 Cities’ circulatory systems (like roads and sewer lines) are decentralized, unlike organisms with a single central circulatory node (e.g., the heart).
• 😀 Cities have polycentric street networks, unlike organisms that follow a single-direction flow (like blood from the heart).
• 😀 The metaphor of cities as organisms isn’t perfect; it can be useful for understanding certain aspects, but doesn’t work for all systems, such as circulation and nervous systems.
• 😀 Cities have been compared to machines, communities, and even crystals, with these metaphors offering insights into design and urban planning, particularly in relation to heat management and energy consumption.

Q & A

What is the main comparison made in the video between cities and organisms?

The video compares cities to organisms, highlighting their similarities in growth, resource distribution, and the way they adapt to changing environments. Both systems consume energy, produce waste, and have circulatory systems that help distribute resources.

How do the metabolic scaling laws in biology relate to cities?

Metabolic scaling laws in biology, which show that larger organisms have more efficient energy consumption, are applied to cities to explain how bigger cities use fewer resources per capita compared to smaller ones. This concept is used to demonstrate that as cities grow, they become more efficient in terms of infrastructure, energy usage, and economic output.

What are some key scaling laws that apply to cities?

Two key scaling laws identified in the video are: first, that larger cities become more efficient in terms of infrastructure like gas stations, roads, and pipes (with a scaling factor of 0.85), and second, that as cities grow, their economic output (wages, GDP, patents) increases more than proportionally (with a scaling factor of 1.15).

How does city size affect its efficiency in terms of infrastructure?

As cities grow, they require more infrastructure, but not in a directly proportional manner. For example, a city with 2 million people does not need twice as many gas stations as a city with 1 million people, but rather about 85% more. This is due to economies of scale that make larger cities more efficient in their infrastructure usage.

What is the difference between how organisms and cities circulate resources?

In organisms, circulation is hierarchical, with a central node (the heart) pumping blood through arteries and veins. In contrast, cities have a decentralized circulation system where streets and traffic are not organized around a single central hub, and traffic often flows between various parts of the city without passing through a central point.

What is meant by the statement that 'a Green Bay is a small Milwaukee'?

This statement refers to how cities of different sizes exhibit similar scaling laws, particularly in terms of their economic and social dynamics. Despite differences in size, smaller cities like Green Bay operate similarly to larger cities like Milwaukee, with scaling factors suggesting that the differences are not as large as they might seem.

What alternative metaphors have been used to describe cities throughout history?

Cities have been compared to machines, organisms, communities, marketplaces, and battlegrounds. These metaphors reflect different perspectives and insights into city design and function, with the machine metaphor being especially popular during the Industrial Revolution due to the rapid technological and infrastructural changes at the time.

Why is the 'city as organism' metaphor not fully applicable to urban planning?

While the 'city as organism' metaphor has some useful applications, like understanding the efficiencies that come with larger cities, it is not always actionable. For example, the metaphor fails to provide detailed recommendations for urban planning, especially when it comes to specific issues like disease, crime, and infrastructure design.

How does the design of a city's street grid impact its urban heat island effect?

The design of a city's street grid can influence its temperature, with rigidly gridded cities (resembling crystals) tending to trap heat more, while more chaotic, less rigidly gridded cities (resembling gases) tend to stay cooler. This understanding can help city planners design cities in a way that mitigates heat retention and reduces energy consumption for cooling.

How might the comparison of cities to crystals, liquids, or gases inform urban planning?

The comparison of cities to crystals, liquids, or gases helps urban planners understand how different city structures can influence environmental factors like the urban heat island effect. For instance, cities designed more like crystals might require more energy for cooling, while cities with a structure similar to gases might naturally stay cooler, influencing the layout of streets and buildings to promote energy efficiency.