How Societies Morph With the Seasons

If you ask a BaYaka Forager in the Central African rainforest, “Where do you live?,” they often reply with a question of their own: “Mouanga or Pela?”

You’ll get the same response for nearly any question about their lives: Who do you live with? Who is this camp’s leader? How do you mourn the dead?

“Mouanga or Pela?”—meaning, “dry or wet season?” The BaYaka’s social world shifts throughout the year. The location and size of their homes, the materials used to build them, leadership, funerals—all transform depending on the season.

As an evolutionary anthropologist working with the BaYaka, I initially presumed people simply adjusted because of the seasonal availability of different foods. But their changes extended way beyond sustenance into the realms of politics, economics, rituals, and relationships.

These shifts starkly contrast with my own homes in the U.K. and Spain, countries seemingly locked into fixed sociopolitical and economic orders. BaYaka flexibility made me rethink my assumptions about what is “natural” for human societies, including gender roles, hierarchies, and social group sizes.

And the more expansively I looked, I realized BaYaka flexibility isn’t the anomaly: The rigidity of industrialized, capitalist societies is. Across history and geography, societies have restructured their sociopolitical and economic lives in response to seasonal shifts—and perhaps not solely due to fluctuating resources. People may also do so because they recognize the dangers of stagnation.

As I see it, regular restructuring keeps communities adaptable and resilient. Solving today’s greatest challenges—inequality, authoritarianism, the climate crisis—may require embracing this flexibility as part of the fabric of our societies.

CATEGORIZING SOCIETIES

Humans, for most of our existence, have lived as hunter-gatherers. Today only a small number of societies still rely on foraging. But studying how these groups adapt to different environments helps evolutionary anthropologists understand how our species became so widespread and successful.

Like our great ape relatives, human foragers often live in what anthropologists call “fission-fusion” societies—fluid systems in which groups come together or split apart depending on the availability of resources. But for chimps, territorial boundaries and rigid dominance hierarchies constrain the possibilities for various social arrangements. Humans, on the other hand, can negotiate their relationships through language, shared conventions, and cultural institutions. This capacity allows for more flexible—and often more egalitarian—forms of social life.

Despite acknowledging this flexibility, many anthropologists and archaeologists have historically classified societies into fixed types. One of the most influential models, developed by U.S. anthropologist Elman Service in the 1960s, proposed four categories: bands, tribes, chiefdoms, and states. In this framework, small, mobile foraging groups (“bands”) are seen as the most basic form of social organization. With time, societies develop into tribes, then chiefdoms, and finally states—along the way, becoming larger, settled, and hierarchical. Those qualities make a society more “complex,” the model suggests.

Over the years, many have questioned and challenged this model: Today’s anthropology textbooks might just mention it as a historical note, rather than a lesson on current thinking. But Service’s basic logic lingers, influencing how both researchers and broader publics tend to view human history: as an inevitable linear progression from mobile to sedentary, egalitarian to hierarchical, simple to complex.

This thinking appears in archaeology too. When researchers uncover changes in tools, architecture, or other archaeological objects, they often assume earlier inhabitants were replaced by outsiders. The newcomers—“advanced” in some way—would bring a different social structure, which could be neatly slotted into one “stage” or another.

I also carried these assumptions into my first field trip with the BaYaka. I arrived in the rainforests of the Congo Basin expecting to find one fixed “type” of society.

SEASONAL SHIFTS

Anthropologists who have worked with the BaYaka often characterized them as “egalitarian” hunter-gatherers. The researchers’ reports say BaYaka live in small, mobile camps and survive primarily on wild yams, honey, and animals such as blue monkeys.

But when I visited the BaYaka in 2023, I witnessed more variation in their lifestyle, depending on the time of year. In February, the communities live in large aggregations near villages, growing manioc and fishing. A few months later, when rains return, these settlements dissolve, and groups of fewer than 15 disperse into the forest to gather honey, caterpillars, and mushrooms.

These shifts in subsistence strategies mean more than just a change in diet: They require entire social reorganizations. Leadership, cooperation, and even spiritual life transform with the seasons. Rituals like Ejengi, which unite hundreds of people in the dry season, become intimate practices among close relatives and friends in the wet season. Other rituals such as Eboka, which commemorates a relative’s death, only occur during the dry season.

And the BaYaka aren’t unique in their cyclical shifts. The 20th-century French anthropologist Claude Lévi-Strauss documented seasonal transformations among the Nambikwara, an Indigenous Amazonian group whose territory today lies in central Brazil. For five months each year, according to Lévi-Strauss, they inhabited large villages, tending small gardens for food. When the dry season began, they dispersed into smaller, mobile foraging groups. These shifts also ushered a reversal of political authority. During the dry season, leaders became authoritative decision-makers, resolving conflicts directly. When the rains returned, the same leaders no longer held coercive power. They could only attempt to influence through tactics like gentle persuasion or caring for the sick.

Similarly, at the turn of the 20th century, anthropologist Franz Boas observed that inequality peaked during the winter among the Kwakiutl, or Kwakwa̱ka̱ʼwakw, a First Nations people along the Pacific Coast of what is now Canada. Boas wrote about Kwakwa̱ka̱ʼwakw winter villages with strict hierarchies and grand ceremonial events. In summer, these rigid structures dissolved as communities broke into smaller, more flexible groups. And rather than people doing this subconsciously solely to adapt to the weather, they were so aware of the political nature of their practices that individuals even changed names when they adopted new social positions for winter ceremonies.

Meanwhile, in my home countries and many others today, institutions seem immutable, changing only during revolutions, coups, or wars.

LOSING EQUALITY

Last January, many watched U.S. President Donald Trump’s inauguration, backed by three men whose combined wealth exceeded that of the poorest 50 percent (more than 165 million) of people in the U.S. Unlike seasonal hunter-gatherers, whose social orders regularly reverse, most people in the “Western world” now live in systems where inequality deepens continuously, with no built-in mechanism to reset the balance.

As scholars deeply concerned with the roots of inequality, the late anthropologist David Graeber and archaeologist David Wengrow asked in The Dawn of Everything:

Many scholars trace inequality’s roots to the advent of agriculture, arguing it “locked in” social hierarchies. The logic is straightforward: Farming allows people to settle in one place and accumulate surplus food and other goods, setting the stage for haves and have-nots. Archaeologists have long assumed this emergent inequality coincided with the appearance of features like elaborate burials or grand monuments. Such structures would exist to celebrate powerful people and require a central authority to command their building, the thinking goes.

But perhaps the archaeological record tells a more complicated story.

Long before farming, during the last ice age, people were already building big. As early as 18,000 years ago, along the glacial fringe from Krakow to Kyiv, hunter-gatherers constructed circular houses out of mammoth bones—structures that some archaeologists describe as early forms of public architecture. These weren’t year-round settlements, based on the presence of bones from seasonally available animals. They appear to have been seasonal aggregation sites, built and occupied temporarily when dispersed groups came together to cooperate, share resources, perform rituals, and then disperse again.

More famously, the massive stone enclosures at Göbekli Tepe in southeast Turkey (often interpreted as “the world’s first temple”) were built over 11,000 years ago by foragers. There is no evidence the site was permanently inhabited nor the product of some big turnover like new migrants or the start of farming. Like the mammoth-bone houses, it may have been a seasonal gathering center built by communities who came together temporarily to create something extraordinary—then walked away.

These cases flip the usual narrative. Instead of assuming that hierarchy is the prize of complexity, these sites suggest not all monumental architecture required a ruling class. For much of human history, societies didn’t follow a single political trajectory—they shifted between different modes of organization, much like the BaYaka do today.

Recognizing humanity’s long tradition of social fluidity puts the present into perspective: The “Western world” is not the culmination of a 10,000-year-long march but an anomaly in a 300,000-year-long history of Homo sapiens’ cultural adaptability.

RECLAIMING SEASONAL FLEXIBILITY

Humans have long managed to restructure their societies with the changing seasons, refuting the narrative that inequality is an inevitable endpoint for us all.

But my point is not that seasonal environments forced humans to remain flexible, and therefore, without seasonality, flexibility wouldn’t exist. Rather, it’s that regularly coping with radically different conditions allowed people to experiment with diverse social and political arrangements. In turn, this adaptability underlies our species’ ability to thrive in almost every ecosystem on Earth.

As Wengrow and Graeber also emphasized, seasonal shifts have no set pattern. The largest rituals occur during the dry season for the BaYaka and during the wet season for the Nambikwara in Amazonia. Among Gabbra pastoralists of northern Kenya, lunar cycles, rather than weather, determine the holy seasons of Soomdeer and Yaaqa, an elder revealed to me recently.