Around 4,600 years ago, communities along the Nile turned stone, transport, skilled labor, food, administration, and religious ritual into monuments built for dead rulers. The pyramids were tombs, but they were also public claims about continuity. A king's body had stopped functioning, yet his relationship with the gods, the political order, and the living population was expected to continue.

Ancient Egyptian funerary monuments became important parts of religion, politics, society, and the economy. The preservation of the body was connected to beliefs that elements of the person could survive death and return to it. Death had become more than a biological event. It had become an institution around which thousands of living people could organize their behavior (Huber et al., 2023).

This presents an evolutionary puzzle. Why would natural selection produce an animal capable of imagining its own disappearance? And once that awareness existed, why did humans respond by building tombs, inventing ancestors, creating afterlives, and organizing entire societies around the dead?

The answer may begin with an ability that evolved for a different purpose: imagining the future.

In brief

Human awareness of death probably did not evolve as a dedicated adaptation for creating religion. It may have emerged from useful abilities for memory, planning, language, social reasoning, and imagining the future. Cultural traditions then transformed mortality awareness into stories, rituals, and institutions. Some of those institutions helped people cooperate beyond family and face-to-face relationships. Others reinforced hierarchy, conflict, and exclusion.

The animal that can imagine its own ending

Every organism behaves in ways that reduce its risk of dying. A gazelle runs from a predator. An insect avoids harmful chemicals. A primate may recognize that an injured group member is in danger.

Avoiding death, however, differs from understanding that one will eventually die.

A developed human concept of death usually includes several connected ideas. The body permanently stops functioning. Death cannot be reversed. All living beings eventually die. Death has physical causes. Most unsettling of all, these rules apply to oneself.

Humans can place themselves inside a future in which they no longer exist. We can plan our funerals, write wills, preserve our names, worry about what others will remember, and imagine events that will happen after we are gone.

Researchers should still be cautious when describing this capacity as exclusively human. Chimpanzees, elephants, cetaceans, corvids, and other animals sometimes respond to dead companions in flexible and emotionally significant ways. Some may understand limited features of death, particularly that an individual has stopped functioning and will not recover. Comparative thanatology—the study of how animals respond to death—has made a simple human-versus-animal division increasingly difficult to defend (Gonçalves & Biro, 2018; Monsó & Osuna-Mascaró, 2021).

There is still no convincing evidence that another species constructs elaborate symbolic accounts of its own inevitable death. No other known animal builds a tomb for an ancestor, promises rewards after death, preserves a ruler for resurrection, or organizes moral obligations around judgment in another world.

Human distinctiveness appears to lie in the combination of death awareness, language, cumulative culture, and shared imagination.

Three possible evolutionary explanations

There are at least three serious hypotheses for how this unusual condition emerged.

Competing hypotheses

1. Death awareness is a cognitive byproduct.
Humans evolved better memory, planning, self-recognition, and future simulation because those capacities improved everyday decisions. Once a person could imagine next winter, tomorrow’s hunt, an approaching conflict, or an unborn child, that same person could imagine a future in which the self was absent.

Prediction: Death awareness should appear alongside the development of future thinking, causal reasoning, language, and a stable concept of the self. The specific afterlife story should vary widely because culture supplies the details.

2. Afterlife beliefs help people manage grief and mortality anxiety.
Humans form long-lasting attachments and continue mentally representing people when they are absent. After someone dies, the social mind may continue asking what that person knows, wants, or feels. Beliefs in spirits and continued existence may grow from the difficulty of switching off a relationship that has existed for years.

Prediction: Beliefs about continued psychological existence should be especially common where emotional attachment remains strong, even when people understand that the body has permanently stopped working.

3. Death narratives became socially useful institutions.
Beliefs about ancestors, judgment, sacred duties, and postmortem consequences may help communities enforce rules and coordinate behavior. Cultural groups with effective rituals and moral institutions may persist, grow, attract members, or compete more successfully.

Prediction: Death beliefs should become more closely tied to morality, authority, and group identity as societies grow and interactions among unrelated strangers become more frequent.

These explanations can operate together. An ability may begin as a byproduct, reduce a psychological cost, and later acquire new cultural functions.

Evolution regularly works with existing materials. A capacity selected for one problem can produce consequences far beyond the original problem.

The future came before the afterlife

A brain capable of imagining future events offers clear benefits.

It can prepare for seasonal shortages, track debts, predict retaliation, choose safer routes, maintain alliances, and invest in children whose eventual economic and reproductive value lies years ahead. Memory also allows people to recombine past experiences into possible future scenarios. That makes planning more flexible.

The cost is that the same mental machinery can simulate illness, loss, abandonment, and death.

Under this hypothesis, natural selection did not favor existential anxiety directly. Mortality awareness came attached to an otherwise valuable package of cognitive abilities. It was a side effect of being able to locate the self across time.

Children’s development offers some support for this interpretation. Young children do not acquire a complete biological understanding of death all at once. They gradually learn that death is irreversible, universal, and associated with the permanent end of bodily functions. At the same time, they encounter religious and cultural accounts in which some part of the person continues. Biological cessation and spiritual continuation can therefore develop beside each other rather than as simple alternatives (Harris, 2018).

This distinction separates two questions that are often mixed together.

The proximate question asks how death beliefs form inside a human mind. Relevant mechanisms include attachment, grief, language, intuitive mind-body separation, agency detection, testimony from trusted adults, and cultural learning.

The ultimate question asks whether any of these beliefs affected survival, reproduction, cooperation, or the persistence of cultural groups.

Evidence for a psychological mechanism does not by itself prove an evolutionary function. A belief can be cognitively attractive without being biologically adaptive. It can also become socially useful long after the mental tendencies supporting it first appeared. Reviews of supernatural belief emphasize this combination of cognitive tendencies, personal experiences, and cultural transmission rather than a single universal cause (van Elk, 2022).

How stories about the dead organize the living

A story can allow people to coordinate without negotiating every rule from the beginning.

Research among the Agta, a hunter-gatherer population in the Philippines, found that stories frequently communicated expectations about cooperation, equality, friendship, and acceptable social behavior. Camps with more skilled storytellers also showed greater cooperation, while skilled storytellers were preferred as social partners. The study does not concern afterlife beliefs specifically, but it demonstrates how narrative can transmit norms and make coordinated behavior easier (Smith et al., 2017).

Stories about death can carry an additional source of authority. The person who enforces the rule does not have to be physically present.

An ancestor may observe whether descendants honor their obligations. A supernatural agent may know whether someone cheated in private. A future judgment may impose consequences after earthly authorities have lost their reach. A sacred story can also define who belongs to the moral community and what sacrifices membership require.

Cross-cultural experiments have found an association between belief in knowledgeable, punitive gods and fairer allocations toward geographically distant people who shared the participant’s religion. This evidence supports a limited claim: some religious beliefs may extend cooperation beyond the immediate village or family. It does not show that religion produces equal concern for all human beings, and it does not establish that moralizing gods caused complex societies to emerge (Purzycki et al., 2016).

The boundary remains important. A religion may widen the cooperative circle from relatives and neighbors to millions of co-believers while drawing a sharper line around outsiders.

That pattern resembles other forms of human alliance management. John Q. Patton’s research in the Ecuadorian Amazon found that meat transfers were directed partly toward political allies. Sharing could recruit support, maintain loyalty, and strengthen coalitions in an unstable political environment. Food was nourishment, but it was also a relationship (Patton, 2005).

Religious narratives can perform a comparable function at a much larger scale. Instead of relying only on meat, direct exchange, or personal familiarity, people can coordinate through shared ancestors, sacred obligations, moral rules, ceremonies, and symbols.

The scale changes. The underlying problem remains recognizable: how do humans know whom to trust, what others expect, and whether cooperation will be returned?

What the pyramids can and cannot prove

The pyramids provide a powerful example of death beliefs becoming embedded in political and economic institutions.

A monumental tomb required surplus production, material transport, craft knowledge, administration, labor coordination, and a legitimate authority capable of directing resources. Belief in the ruler’s continued existence helped place those activities inside a shared cosmology. The political hierarchy could be presented as part of an enduring sacred order rather than a temporary arrangement among living people.

This does not prove that afterlife belief originally evolved to improve group survival.

The pyramids were built thousands of years after humans had already developed language, mortuary practices, social identities, and supernatural traditions. They show what states could do with beliefs about death once those beliefs had become culturally established. They do not reveal the original evolutionary cause of those beliefs.

Several incentives probably converged.

Rulers gained legitimacy. Elites gained status. Priests and specialists gained institutional roles. Workers received provisions and participated in a state project. Families preserved connections to the dead. The wider population encountered a visible demonstration of political and sacred authority.

A monument can serve several functions simultaneously. Ancient Egyptians did not need to consciously think, “This project increases group fitness.” Selection does not require an organism to understand the eventual consequences of its behavior.

The more defensible interpretation is that death beliefs became culturally available tools. Political institutions then used those tools to organize labor, express hierarchy, connect generations, and make social order appear permanent.

Where cultural group selection fits

The phrase group selection can cause confusion because it refers to several related arguments.

A strong biological claim would propose that an inherited capacity for death awareness spread because groups whose members possessed it survived or reproduced better than competing groups. Direct evidence for this claim is currently weak. We do not know when full personal mortality awareness appeared, how much heritable variation existed, or whether differences in that capacity changed group survival.

Cultural group selection is a narrower and more plausible possibility.

Cultural groups differ in their institutions, norms, rituals, and methods of social control. These practices are learned rather than transmitted only through genes. Groups with stronger coordination may expand, attract converts, absorb migrants, preserve their institutions, or prevail in competition. People entering a group can adopt its practices, allowing cultural differences to remain meaningful even when genes move between populations.

Research among pastoral communities in Kenya found that cooperation between groups was associated with cultural similarity, supporting a key prediction of cultural group selection. The authors treat this as evidence that cooperative norms may be shaped by competition among culturally differentiated populations, while acknowledging that the theory remains difficult to test directly (Handley & Mathew, 2020).

Multilevel selection models likewise examine how selection can act through both individual and group-level outcomes. Nowak, Tarnita, and Wilson used this approach to analyze eusociality and suggested that parallels with human social evolution deserve investigation. Their work does not demonstrate that religion or death awareness evolved through group selection, but it provides a framework for asking how group-level organization can influence evolutionary outcomes (Nowak et al., 2010).

The safest conclusion is therefore conditional: afterlife beliefs may have contributed to the success of some cultural groups under some historical conditions. They were one mechanism among kinship, reciprocity, punishment, reputation, trade, warfare, law, and political authority.

Death can strengthen cooperation and hostility

A shared story about death can bring people together. It can also make compromise harder.

Terror management theory proposes that awareness of mortality increases people’s attachment to cultural worldviews that provide meaning, value, and either literal or symbolic continuity. Literal continuity includes an afterlife. Symbolic continuity includes children, nations, monuments, books, institutions, and reputations that remain after the body is gone.

A major meta-analysis covering 277 experiments reported that reminders of death were associated with stronger defense of cultural worldviews and self-esteem (Burke et al., 2010).

This evidence requires caution. Later preregistered and replication studies have failed to reproduce several well-known mortality-salience effects. Terror management theory remains influential, but some of its experimental findings are less secure than earlier summaries implied (Treger et al., 2023).

The broader anthropological pattern is still plausible without accepting every claim made by terror management theory. Threats often increase reliance on trusted identities, familiar norms, and dependable coalitions. Death is the final threat, and cultures provide languages for managing it.

The social effects depend on the content of the norm.

A tradition that defines generosity, forgiveness, and care as sacred may increase those behaviors. A tradition that treats outsiders as dangerous or impure may intensify exclusion. The same psychological commitment that supports sacrifice for fellow members can support aggression toward a rival group.

Death awareness may therefore expand cooperation inside a moral boundary while raising the cost of crossing it.

Evidence, interpretation, and speculation

Evidence: Humans explicitly represent personal mortality, create culturally transmitted accounts of postmortem existence, and build institutions around the dead. Some nonhuman animals may understand limited properties of death, but no other known species has produced comparable symbolic systems.

Interpretation: Personal mortality awareness probably emerged from a combination of future simulation, self-awareness, social cognition, language, and cumulative culture. Afterlife beliefs draw support from attachment, intuitive psychological reasoning, testimony, ritual, and social learning.

Speculation: Cultural groups with compelling death narratives may sometimes have coordinated larger populations, enforced obligations more effectively, and preserved institutions across generations. This could have contributed to cultural group selection, although current evidence cannot establish it as the original reason humans became aware of death.

What would change my mind?

• Evidence that another species can represent its own inevitable future death and communicate that concept symbolically would weaken claims of strong human uniqueness.
• Archaeological evidence linking the earliest mortuary behavior directly to beliefs about moral judgment or large-scale cooperation would strengthen the institutional hypothesis.
• Cross-cultural evidence showing that afterlife beliefs consistently appear before wider cooperative institutions would support a causal role for those beliefs.
• Strong evidence that death-related beliefs have no measurable relationship with trust, coordination, identity, or institutional persistence would weaken the cultural group selection argument.
• Replicable experiments showing that mortality reminders reliably increase universal cooperation, rather than context-dependent loyalty, would change the conclusion about cooperative boundaries.

Key takeaways

• Humans are the only known species to build explicit symbolic systems around their own inevitable death, although some animals may understand limited aspects of death.
• Mortality awareness may be a consequence of cognitive abilities selected for planning, memory, social reasoning, and imagining the future.
• Afterlife beliefs can emerge from grief, attachment, intuitive mind-body separation, cultural testimony, and the difficulty of imagining personal nonexistence.
• Stories about death can transmit norms, preserve authority, and coordinate people who are unrelated and may never meet.
• Religious cooperation is often bounded. Shared beliefs may extend trust among co-believers while strengthening divisions from outsiders.
• Cultural group selection offers a plausible account of how effective death-related institutions could spread, but it does not establish why death awareness originally evolved.
• The pyramids show the institutional power of afterlife beliefs. They do not prove that awareness of death was selected for the benefit of groups.

Editorial note: This article examines how beliefs about death may form and spread. It does not attempt to prove or disprove religious claims about an afterlife.

References and further reading

Burke, B. L., Martens, A., & Faucher, E. H. (2010). Two decades of terror management theory: A meta-analysis of mortality salience research. Personality and Social Psychology Review, 14(2), 155–195.

Gonçalves, A., & Biro, D. (2018). Comparative thanatology, an integrative approach: Exploring sensory and cognitive aspects of death recognition in vertebrates and invertebrates. Philosophical Transactions of the Royal Society B: Biological Sciences, 373(1754), 20170263.

Handley, C., & Mathew, S. (2020). Human large-scale cooperation as a product of competition between cultural groups. Nature Communications, 11, 702.

Harris, P. L. (2018). Children’s understanding of death: From biology to religion. Philosophical Transactions of the Royal Society B: Biological Sciences, 373(1754), 20170266.

Huber, B., Hammann, S., Loeben, C. E., Jha, D. K., Vassão, D. G., Larsen, T., Spengler, R. N., Fuller, D. Q., Roberts, P., Devièse, T., & Boivin, N. (2023). Biomolecular characterization of 3500-year-old ancient Egyptian mummification balms from the Valley of the Kings. Scientific Reports, 13, 12477.

Monsó, S., & Osuna-Mascaró, A. J. (2021). Death is common, so is understanding it: The concept of death in other species. Synthese, 199, 2251–2275.

Nowak, M. A., Tarnita, C. E., & Wilson, E. O. (2010). The evolution of eusociality. Nature, 466, 1057–1062.

Patton, J. Q. (2005). Meat sharing for coalitional support. Evolution and Human Behavior, 26(2), 137–157.

Purzycki, B. G., Apicella, C., Atkinson, Q. D., Cohen, E., McNamara, R. A., Willard, A. K., Xygalatas, D., Norenzayan, A., & Henrich, J. (2016). Moralistic gods, supernatural punishment and the expansion of human sociality. Nature, 530(7590), 327–330.

Smith, D., Schlaepfer, P., Major, K., Dyble, M., Page, A. E., Thompson, J., Chaudhary, N., Salali, G. D., Mace, R., Astete, L., Ngales, M., Vinicius, L., & Migliano, A. B. (2017). Cooperation and the evolution of hunter-gatherer storytelling. Nature Communications, 8, 1853.

Treger, S., Benau, E. M., & Timko, C. A. (2023). Not so terrifying after all? A set of failed replications of the mortality salience effects of terror management theory. PLOS ONE, 18(5), e0285267.

van Elk, M. (2022). Proximate and ultimate causes of supernatural beliefs. Frontiers in Psychology, 13, 949131.