Beyond the Gene: Exploring Multi-Dimensional Inheritance Systems

1 Rethinking Inheritance — Genes Are Only Part of the Story

Inheritance is often equated with genes, those sequences of DNA that carry the blueprint for life. Since the discovery of DNA’s structure in the mid-20th century, genes have been cast as the central actors in heredity and evolution. This gene-centric view shaped decades of research and popular understanding alike, positioning DNA as the sole vehicle of biological information passed from one generation to the next.

Yet, as compelling as the gene-focused model has been, it now faces important challenges. An expanding body of evidence reveals that inheritance is far more complex and multi-dimensional. Organisms inherit not only genetic sequences but also a variety of other factors that influence development and adaptation, including epigenetic modifications, ecological legacies, behavioural patterns, and, in the case of humans and some other species, cultural knowledge. These different modes of inheritance operate simultaneously and interactively, contributing to the continuity and diversity of life in ways that cannot be fully explained by DNA alone.

Why has the gene remained so dominant in heredity studies? Part of the answer lies in its clarity and elegance: genes provide a discrete, molecular unit of inheritance that is relatively easy to identify and manipulate. The discovery of the genetic code and the central dogma of molecular biology (DNA makes RNA makes protein) gave the impression that life’s mysteries could be largely reduced to genetic sequences. This perspective, sometimes called genetic determinism, implied that organisms were essentially the sum of their genes, with the environment playing a secondary or permissive role.

However, this model has been increasingly called into question. A growing number of studies show that factors beyond DNA sequence can be inherited and influence phenotypes — the observable traits and behaviours of organisms. Epigenetic mechanisms, for instance, involve chemical modifications to DNA or associated proteins that regulate gene activity without changing the underlying sequence. These modifications can be influenced by environmental conditions and, crucially, can be transmitted across generations. Similarly, ecological inheritance refers to the transmission of environmental features altered or maintained by organisms themselves, such as nest sites or microbial communities, which then shape the development and survival of descendants.

Behavioural inheritance adds another layer. Many animals learn behaviours from their parents or social groups, passing on survival strategies and social norms independent of genetic code. In humans, cultural inheritance — the transmission of language, tools, customs, and knowledge — represents a powerful force shaping evolution, with feedback effects on biology and society.

Recognising these multiple channels of inheritance demands a broader, relational framework. Inheritance is not a linear transfer of genetic information but a dynamic process involving the interplay of genes, environments, behaviours, and cultures. This relational view better captures how organisms develop and adapt in complex, changing worlds.

In this series, we will examine each of these inheritance systems in detail, exploring their mechanisms, empirical evidence, and evolutionary significance. We will also discuss how this multi-dimensional perspective reshapes longstanding debates in biology and philosophy, opening new pathways for understanding life’s continuity and change.

The gene remains essential, but it is only part of the story. Broadening our view to encompass multi-dimensional inheritance enriches our grasp of biology and invites us to rethink what it means to inherit, to evolve, and ultimately to be alive.

2 Epigenetic Inheritance — Regulating Genes Beyond the Sequence

If genes are the text, epigenetics is the punctuation — subtle, powerful, and capable of altering the message without changing the words themselves. The term epigenetics refers to the molecular mechanisms that regulate gene expression without altering the underlying DNA sequence. These mechanisms help determine when, where, and how strongly genes are turned on or off. Crucially, some of these modifications can be transmitted across generations, providing a mode of inheritance that works independently of changes in gene sequence.

The most well-known epigenetic mechanisms include:

• DNA methylation, the addition of methyl groups to specific sites on DNA, which typically reduces gene expression;

• Histone modification, the chemical tagging of proteins around which DNA is wrapped, altering how accessible genes are to transcription machinery;

• Non-coding RNAs, which can modulate gene expression by interacting with mRNA or chromatin.

These mechanisms form a flexible system of regulation — one that is responsive to internal development and external environment alike.

Transgenerational inheritance of epigenetic modifications has now been observed in a wide range of species, from plants and insects to mammals. In some cases, environmental stresses — such as temperature changes, toxins, or nutrient availability — can trigger epigenetic changes that persist for several generations. This has been particularly well documented in plants, whose development is tightly coupled to environmental variability. For example, as discussed in our recent series on rice, exposure to cold conditions over multiple generations led to inheritable changes in DNA methylation that conferred cold tolerance, without altering the DNA sequence.

In mammals, the evidence is more complex and sometimes contested, given the extensive epigenetic “reprogramming” that occurs during the formation of gametes and early embryonic development. Nevertheless, studies have found that certain environmental exposures — including stress, diet, and toxic chemicals — can leave epigenetic marks that persist across one or more generations. For example, rodent studies have shown that offspring of parents exposed to specific diets or stressors can exhibit changes in metabolism, behaviour, and disease susceptibility — even when the DNA sequence remains unchanged.

Such findings challenge the long-held assumption that inheritance is purely genetic. They show that environmental experiences can be biologically embedded and transmitted — not by altering the gene, but by regulating its expression. This raises difficult questions about how to define heritability and where to draw the boundary between organism and environment in evolutionary explanation.

Epigenetic inheritance also disrupts the traditional view of the environment as an external backdrop against which genes unfold. Instead, it suggests a more dynamic relationship: the environment becomes an active participant in shaping the heritable regulation of gene activity. This is not a rejection of natural selection, but it does extend the range of mechanisms through which variation arises and persists.

Moreover, epigenetics reintroduces a sense of biological plasticity — the capacity for organisms to modulate their development and physiology in response to conditions they encounter. And when these responses become heritable, they offer a pathway for non-genetic adaptation, especially in timescales shorter than those typically required for mutational change.

Yet it’s important to avoid swinging too far in the opposite direction. Not all environmentally induced epigenetic changes are stable across generations, and many are reset or erased. The mechanisms that determine which changes persist and which do not are not yet fully understood. But the existence of stable epigenetic inheritance, even in a subset of cases, calls for an expanded theory of heredity — one that includes regulation, responsiveness, and relationality as core principles.

In the next post, we will explore a different but complementary mode of inheritance: ecological inheritance — the legacy of modified environments, habitats, and niches passed from one generation to the next.

3 Ecological Inheritance — Passing On Modified Worlds

Organisms do not inherit only genes, or even just regulatory systems like those involved in epigenetic inheritance. They also inherit worlds. From beavers who pass on dammed rivers to their offspring, to humans who inherit cities, languages, and institutions, organisms routinely inherit environments that have been altered by the activities of previous generations. This process — known as ecological inheritance — is a key component of what some evolutionary biologists call niche construction theory.

Niche construction refers to the ways in which organisms actively modify their environments in ways that feed back into their own development and evolution. These modifications — from burrows, webs, and nests, to chemical gradients, fire regimes, and landscapes — can persist beyond the lifetime of the organism, shaping the selective pressures and developmental pathways faced by their descendants.

In ecological inheritance, the effects of past modifications are not merely incidental. They constitute a transmitted legacy — a transformed context of development, in which the activities of ancestors continue to exert influence. Crucially, this inheritance is not genetic: it operates through persistence in the environment and the patterned behaviours that reproduce it. Yet it has evolutionary consequences just as real.

For instance, earthworms modify soil structure, nutrient availability, and microbial communities. These environmental changes persist and influence the development, survival, and reproduction of subsequent generations. Likewise, the mounds built by termites alter airflow, temperature, and humidity, providing a regulated microclimate for the colony's descendants.

In humans, ecological inheritance becomes even more pronounced. Our cultural practices — agriculture, urbanisation, architecture — leave behind materially altered environments that shape developmental trajectories over time. A child raised in a literate, urban society does not inherit only a genome and a set of epigenetic regulations; they also inherit a built environment, a material infrastructure, and a set of social expectations that profoundly influence what kinds of beings they can become.

Ecological inheritance brings attention to the role of organism–environment feedback loops in evolution. Rather than treating the environment as a static backdrop, this perspective sees it as a dynamic and partly organism-constructed field of interaction. Organisms do not just adapt to their environments; they also adapt their environments to themselves — and pass on these changes.

This mode of inheritance also challenges the assumption that evolutionary causality flows in a single direction: from genes to traits, and from traits to fitness. Instead, ecological inheritance suggests that causality is distributed across time and space, entangled in a web of activities, modifications, and reciprocities.

It also blurs the line between inheritance and development. What counts as “inherited” in this framework is not always transmitted via gametes, nor even via the body of the parent. It includes legacies embedded in places, patterns, and practices — in what the philosopher of biology Richard Lewontin once called “the organism–environment dialectic.”

In the next post, we will continue our exploration by turning to behavioural inheritance — another pathway through which living systems transmit adaptive strategies across generations.

4 Behavioural Inheritance — Repertoires of Doing

Living beings do not begin their lives from a blank slate. In addition to inheriting genes, epigenetic configurations, and ecologically modified worlds, many organisms also inherit patterned behaviours — ways of doing, responding, and interacting that shape their development from the start. This is known as behavioural inheritance, and it is especially prominent in animals with extended parental care or social learning.

Behavioural inheritance involves the transmission of actions, skills, and routines across generations. These are not simply instinctual, hard-wired reflexes coded by genes; rather, they are often acquired through interaction, observation, imitation, and participation. They include foraging strategies, vocalisations, predator avoidance, mating rituals, tool use, migratory routes, and much more. In this sense, behaviour is not just an outcome of inheritance — it is also a medium of inheritance.

Consider the song dialects of birds. Young songbirds raised in isolation from adult models will fail to develop species-typical songs. But when exposed to singing adults during critical learning periods, they acquire specific regional variations — dialects — that are transmitted culturally rather than genetically. These learned songs are essential to mate attraction and reproductive success, shaping fitness outcomes across generations.

Or consider migratory knowledge in animals such as cranes, elephants, and whales. These long-distance movements often depend on behavioural traditions passed down from elders — knowledge of timing, routes, and destinations that cannot be derived from genetic instructions alone. When such knowledge is lost (as in disrupted or fragmented populations), migratory behaviours can fail to re-establish, even when habitats are restored.

In humans, behavioural inheritance is foundational. From gestures and habits to speech patterns and moral norms, children inherit a rich repertoire of practices long before they understand them as such. This inheritance is largely tacit and embodied. It takes place through immersion in a social world: watching, mimicking, playing, being corrected, being praised. It is how a child learns to walk, to greet, to take turns, to speak — how they come to inhabit a particular form of life.

Behavioural inheritance also works in tandem with ecological and symbolic systems. A ritual, for example, is both a repeated behaviour and an enactment within a culturally shaped space. A cooking technique is at once a practical skill and a way of reproducing taste, memory, and identity. Through behaviour, organisms not only adapt to environments but reproduce the very conditions of their meaningfulness.

Crucially, behavioural inheritance is not limited to conscious teaching. It can be implicit and unintentional — a matter of what is modelled, made available, or expected. It is also subject to variation and innovation, especially in species capable of learning. Thus, behavioural traditions can drift, diversify, or be recombined, contributing to evolutionary change not just as background noise, but as active variation in the developmental landscape.

The implications are significant. Behavioural inheritance demonstrates that evolution does not operate only through genetic variation filtered by selection. It includes the passing on of ways of doing, knowing, and relating that shape organisms from their earliest encounters with the world. This adds another layer of relationality to the evolutionary process: not only are organisms co-constituted with their environments, they are also co-constituted with the actions and interactions of others — across time.

In the next post, we will turn to symbolic inheritance, a uniquely human system that extends behavioural inheritance into the realm of shared meaning — and into new evolutionary dynamics.

5 Symbolic Inheritance — The Transmission of Meaning

Among all forms of inheritance, symbolic inheritance stands out as uniquely human. It encompasses the transmission of meanings, classifications, categories, and codes — the semiotic scaffolding through which we interpret and participate in the world. From language to law, kinship to cosmology, humans inherit symbolic systems that profoundly shape their capacities, identities, and actions.

Whereas behavioural inheritance involves repertoires of doing, symbolic inheritance involves repertoires of meaning. These meanings are not confined to individual experience but are distributed across time and community. They are instantiated in speech and writing, ritual and myth, architecture and art. They shape how we make sense of experience, how we structure our societies, and how we imagine what is possible.

Language is the paradigmatic case. A child born into a linguistic community inherits not only the capacity for language (a biological potential), but also a specific language — a historically evolved system of meaning-making. This system comes with grammatical categories, distinctions, metaphors, and norms of interaction. Through it, the child learns not just to label objects, but to construe relationships, to project identity, to negotiate obligations, and to participate in shared worlds.

Symbolic inheritance operates through what we might call semiotic niches — socially and materially supported systems of signification. These niches include not only language, but also legal codes, religious symbols, measurement systems, digital protocols, and scientific taxonomies. They organise social life, regulate behaviour, and orient perception. They are not innate, but must be learned, interpreted, and enacted — often in ways so routine they feel natural.

Importantly, symbolic systems are not merely transmitted intact. They are dynamically re-instantiated by their users. Each utterance, performance, or interpretation both reproduces and slightly modifies the system. This means that symbolic inheritance is not static, but evolutionary — shaped by cumulative history, social negotiation, and shifting contexts. It is also generative, enabling new configurations of meaning, identity, and value.

From the perspective of relational ontology, symbolic inheritance exemplifies the idea that to know is to participate. One does not acquire knowledge as an object; one enters into a community of practice, a shared history of sense-making. The meanings one inherits are not private contents in the mind but public affordances for interaction — ways of engaging with others, with the world, and with oneself.

This has profound implications for how we understand evolution, development, and culture. In symbolic inheritance, the evolutionary process extends far beyond genes and behaviours. It includes the historical sedimentation and transformation of meanings — of how beings come to matter, to themselves and each other. It is here that human development most clearly transcends individual biology: to become human is not just to develop a body and brain, but to inherit a way of making the world intelligible.

In the final post, we will draw these threads together — genetic, epigenetic, ecological, behavioural, and symbolic — into a unified relational picture of inheritance, and explore what it means to think evolution beyond the gene.

---

6 Inheritance as Participation — A Relational Synthesis

Across the preceding posts, we’ve traced a widening arc of inheritance: from the molecular transmission of DNA to the transmission of meanings in symbolic form. Each step has expanded our understanding of what it means to inherit — and what it means to evolve. In this concluding post, we bring these threads together under a relational ontology of inheritance, in which to inherit is not merely to receive, but to participate.

The classical gene-centric model of inheritance treats inheritance as a linear flow of information from genes to traits to fitness. Within this framework, causality is largely unidirectional, and the environment functions as a backdrop to genetic action. But as we have seen, inheritance is not confined to genes. It operates at multiple levels — epigenetic, ecological, behavioural, and symbolic — and through multiple media — chemical, structural, social, and semiotic.

A relational perspective reframes inheritance not as the transmission of static units, but as the ongoing entanglement of beings and their contexts. To inherit, in this view, is to enter into a history of activity: to take up a position in a world already shaped by others, and to participate in its further shaping. Each inheritance is a joining-in — a co-constitution of self and world through processes of mutual becoming.

This means that inheritance is not only biological but developmental, ecological, and cultural. It is not just what an organism has, but what it does — and what it becomes-with. An inherited gene, for instance, has no meaning or effect apart from the networks of regulation, interaction, and environment in which it is embedded. Likewise, inherited behaviours, environments, and meanings derive their force from participation in ongoing patterns of activity.

Importantly, this relational view does not deny the role of genes — but it decentres them. It treats genes not as master codes but as one element in a distributed system of inheritance, in which many forms of historical influence co-exist and co-act. This shift mirrors broader moves in biology and philosophy that emphasise systems, processes, and interactions over discrete, isolatable causes.

It also highlights the role of meaning in evolution. As symbolic inheritors, humans do not merely pass on traits or strategies; we pass on ways of making sense of ourselves and our world. These ways are not fixed, but responsive, capable of transformation in light of new experiences and commitments. In this sense, symbolic inheritance is not the end point of evolution, but its deepening — a turn toward the reflexive, the ethical, and the possible.

A relational ontology of inheritance offers a vision of life not as the competition of gene-bearing individuals, but as a tapestry of intergenerational commitments, reciprocities, and co-creations. It encourages us to see ourselves not as autonomous actors, but as participants in histories that precede us and futures that depend on us. Inheriting, then, is not just something we undergo — it is something we do.

To inherit, in this view, is not to carry a past but to carry it forward — to live it, rework it, and offer it again. It is to participate in the world as a process of transmission and transformation. And in doing so, to recognise that evolution is not only what brought us here, but what we do together, now.