How Has Living in Crowded and Densely Populated Communities Changed Humans Over the Last 10,000 Years? — Here’s What Researchers Discovered

About 10,000 years ago, humans began to live in densely populated communities. This is because of the advent of farming and agriculture, which allowed societies to support more individuals. Before, they were living in much smaller groups as hunter-gatherers. This meant that they were totally dependent on what nature could provide.

In other words, they scavenged, foraged, hunted, and gathered resources that were readily available, but when their habitat was depleted, they needed to migrate to other locations with more abundant provisions. But, with farming, they could grow their own food supply and stay in one place, which would make births safer and more frequent, leading to a higher birth rate.

The increase in the reliability of food also allowed more people to survive until adulthood, along with many other factors. Over time, their population grew, and more people lived together in one place and in a crowded community. But, how exactly did this transition change humans over the last 10,000 years? Did it affect our physiology, behavior, and more? Let’s discuss it deeper in this article.

Health, Disease, and Exposure in Dense Communities

During the early days of farming, living together at the same place with a more reliable food supply was not devoid of problems and challenges. This phenomenon resulted in humans having less nutrition in their diet, because early farming made their food supply have less variation compared to hunter-gatherers.

Before farming, humans would hunt different animals for meat, collect wild plants, and then move to another location once the habitat got depleted for any reason like climate change. But with farming, they could only plant select types of seeds and crops. Along with a limited number of domesticated animals, their diet became less nutritious overall.

Additionally, one of the most significant changes during the transition to agricultural societies was how fast a disease could spread with more humans and animals living together near each other. The pathogens and parasites could easily and quickly pass from one person to another, creating epidemics that could put the survival of the whole group in danger.

Moreover, living in a more populated community could also mean poorer hygiene, sanitation, and waste management. These circumstances would make it highly likely that an individual would be exposed to some form of disease or sickness. Over time, these problems may have created pressure for humans to develop a better immune system and develop growth and social responses to reduce the risks, changing the way they interact and cooperate.

Read more: PubMed Central

Social Life, Interaction, Cooperation—and Stress

How Living In Cities Is Evidence Of Human Evolution

The rise of farming allowed humans to live in larger communities, but it also led to the formation of a more complex social hierarchy in their groups. With an increasing population, there was also a growing number of disputes and conflicts. This was because farming led to the concept of ownership.

A productive farm could lead to an abundant and reliable food supply, which results in a surplus. Along with the development of permanent homes, people began to take ownership of their lands and resources. These events changed the way they interacted and cooperated within the group.

With farming, it also means that not everyone needs to work on food production. This led to the creation of specialized roles, such as artisans to create potteries or builders to build permanent settlements. But it also allowed a managerial position to be born, where a competent individual viewed by the group would be in charge of the distribution of the food supply.

It could be someone who was a really strong fighter capable of fending off enemies away from their territory, or a knowledgeable person who could make the farm run more efficiently. Soon, these individuals began to accumulate power, status, and wealth that they were able to pass to their children, leading to the concept of inheritance.

Compared to hunter-gatherer societies, living in densely populated communities led to humans having more different specialized roles, and they began to transition from mostly egalitarian to hierarchical societies. Over time, these social dynamics just became solidified, with people being born into different social standings.

For a more detailed explanation of this specific concept, you can head on here: How Did Early Farming Around 10,000 Years Ago Lead to the More Complex Social Hierarchies of Humans? — Here’s What Researchers Found

Biological and Behavioral Changes in Humans

Another possible result of living together in high-population cities and societies is changes in human biology and behavior. Before farming, hunter-gatherers would perform strenuous tasks on almost a daily basis. They would hunt prey for hours, run from predators, climb rocky mountains, walk long distances, and more. They also had a more varied diet from their nomadic lifestyle, which is believed to be more nutritious than the early farmers’ diet, which consisted of a few select grains or crops.

However, farming societies with dense populations are different. Their jobs are still hard, but are repetitive and specialized. So, these factors that were gone may have reduced the selective pressure for humans to have bigger, stronger, and taller bodies. In short, their new lifestyle may have contributed to the downward trend of humans being shorter, weaker, and smaller. It was only recently, the last few centuries, that humans have begun to reverse the trend and continue growing again on average as a species.

Additionally, anthropologist Robin Dunbar suggests that humans could only maintain up to 150 stable social relationships. But, with the advent of farming that led to thousands of people living together, to eventually millions in one city, humans may have needed to become more socially skilled at managing relationships and networks with complete strangers.

This may sound normal now, because in the modern world, we usually interact with strangers either online or in person on a daily basis. But before living in dense communities, humans and other hominins usually had an intimate relationship with one another in their group. Surviving with strangers would be uncommon.

In short, the transition to managing life in larger and complex societies may have put additional evolutionary pressure on humans to change or improve their social cognition, eventually prompting a behavioral shift.

Read more: The University of Chicago Press Journal

Culture, Technology, and Innovation in Dense Settlements

What LIFE Was Like Before the First Cities? - 10,000 BCE

Largely and densely populated societies usually become the center of innovation. This is because with more people, there could be more specialized roles and unique ideas. This is why the advent of farming around 10,000 years ago also led to one of the most significant technological revolutions of human history.

The specialized roles of early farmers led to the improvement of old tools or the innovation of new technologies. Examples include the refinement of stone tools for harvesting and processing crops, and the invention of potteries and underground pits to store those food supplies.

Over time, as societies became more complex, population rises, and organized governments have been developed, the ability of humans to create and innovate has become grander. They began building large-scale technologies like irrigation systems, defensive walls, and monumental structures like temples and palaces. These are all previously impossible to achieve by nomadic hunter-gatherers. They have only been possible because of humans living in one place together in great numbers.

Author's Final Thoughts

Humans living in dense communities had profound effects on our behaviors, biology, and eventually history. This phenomenon helped us create the human civilization that we know today. But, yes, it may have had some setbacks, like faster spread of diseases and the need to manage complex and numerous relationships and social interactions even with strangers.

However, these factors may have also added pressure for our species to develop even further. Without both the challenges and the benefits that living together in greater numbers gave us, we may have never been the humans we came to be.

Read next: Why Have Humans Gotten Shorter Since About 10,000 Years Ago, and What’s Currently Reversing It? — Here’s What Scientists Found

References & Further Reading

Larsen, C. S. (1995). Biological changes in human populations with agriculture. Annual Review of Anthropology. https://www.annualreviews.org/doi/10.1146/annurev.an.24.100195.001153

Mathieson, I., et al. (2015). Genome-wide patterns of selection in 230 ancient Eurasians. Nature. https://www.nature.com/articles/nature16152

Andrades Valtueña, A., et al. (2022). Stone Age Yersinia pestis genomes shed light on the early evolution, diversity, and ecology of plague. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.2116722119

Hanski, I., et al. (2012). Environmental biodiversity, human microbiota, and allergy are interrelated. Proceedings of the National Academy of Sciences. https://www.pnas.org/doi/10.1073/pnas.1205624109

Field, Y., et al. (2016). Detection of human adaptation during the past 2,000 years. Proceedings of the National Academy of Sciences. https://pmc.ncbi.nlm.nih.gov/articles/PMC5182071/