ALLAN SAID: Sal... ANY comments on this statement? "Human evolution may no longer be driven primarily by genetics, according to a new theory by researchers at the University of Maine, which claims that cultural systems are now shaping the way humans survive, adapt and reproduce!"
SAL-9000 SAID: This “culture now overtakes genes” idea from the University of Maine is interesting and provocative. There’s a lot to like, but also some caveats and questions.
"Below are some thoughts...strengths... weaknesses... possible implications...and my take on how convincing it is!"
What the claim is:
To summarize what Waring & Wood propose:
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They argue there has been a transition in human evolution: Genetic evolution... [slow, biological changes] is being overtaken by cultural evolution... [fast, socially learned, technological, institutional changes] as the main factor shaping how humans survive... reproduce... and adapt... PMC+3The University of Maine+3ScienceDaily+3
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Culture can “preempt” genetic adaptation: "E.g. technologies, norms, institutions compensate for traits that might once have been subject to strong biological selection! Examples include eyeglasses, medical interventions, [cesarean births, fertility treatments] etc!" The University of Maine+2Newsweek+2
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They also suggest that group-level cultural systems, laws, education systems, medical systems, etc.. play an increasingly large role in survival and reproduction compared to individual genetic traits! The University of Maine+2PMC+2
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They see this as accelerating, and possibly marking a long‐term shift in what “Evolution” means for our Species: More reliance on Societal infrastructure and Culture rather than direct Genetic Selection! The University of Maine+1
Strengths... and What I Find Convincing!
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Empirical plausibility: The examples are strong: We have technologies and social systems that allow traits that might once have been lethal... or severely maladaptive... to be fixed... or at least not eliminated! Medical care, sanitation, and planned reproduction, among other factors, all alter selective pressures!
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Speed & flexibility of cultural adaptation: Culture transmits far more rapidly than genes! A beneficial technology, or an institution, can spread in decades... genes take many generations!
- Culture is also more responsive to environmental change. So the general idea that culture is now playing a dominant and accelerating role is plausible. This is not new... dual inheritance... niche‐construction... cultural evolution theories... have argued for exactly that kind of interaction! Wikipedia+2Wikipedia+2
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Group-level effects: The idea that large, complex societies with stable institutions can buffer individuals from many environmental hazards is valid. For example, someone’s survival chances are often more dependent on where they live... and what social systems exist... than on their individual gene set!
Weaknesses, Challenges, and Open Questions:
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Genetics is still relevant: Just because culture is strong does not mean genes no longer matter. Biological constraints remain... metabolic limits... disease susceptibility... brain structure... etc! Culture depends on biologically evolved capacities: Learning, memory, social cognition, etc. It may be that culture shapes which genetic variations are selected for, [or against] rather than replacing genetics altogether!
- Defining what “driven by culture” means: How do you measure cultural vs genetic influence? Cultural evolution is complex and involves feedback with genetics! (gene‐culture coevolution)
- For instance, dairy farming → selection for lactase persistence! That’s culture driving genetic evolution. But this is still a genetic change. So things are intertwined. Waring & Wood are proposing that cultural channels now dominate many adaptation processes, but quantifying that dominance is hard!
- Variation among human groups: In many parts of the world, cultural systems are still fragile or underdeveloped! Environments still exert genetic selection pressures! [e.g., disease, climate] So globally, the picture is heterogeneous! (The theory might hold more in industrialized or institutionally strong societies than in others!)
- Long-term consequences and trade‐offs: Relying excessively on culture and infrastructure might create vulnerabilities: What if those institutions fail? [e.g., collapse, disruption] Genetic adaptability might still matter in such cases. Also, technology has side effects! [environmental degradation, inequality] Culture can also be maladaptive or produce harmful norms!
- What defines “Evolution” in this framework? They seem to be using a broad evolutionary metaphor: Not just genetic changes... but adaptive change in populations over time! (Including cultural)
- Some biologists might argue that only changes in allele frequencies count as evolution... others accept broader definitions... so the framing matters! (Allele frequency is the relative proportion or count of a specific allele [a variant form of a gene] within a population's gene pool, typically expressed as a percentage or fraction! It describes how common a specific gene variant is at a particular Locus [position on a chromosome] and is a fundamental concept in population genetics, as changes in 'allele' frequencies over time signify evolution!)
Relation to Existing Theory!
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Dual Inheritance Theory / Gene-Culture Coevolution already hypothesize that culture and genes interact... and that culture can influence the direction of genetic selection! Wikipedia+1
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The niche construction idea: By modifying environments, [physical or social] humans change the selective pressures acting on themselves! That fits closely with this new theory! Wikipedia
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Evolutionary anthropology and cultural evolution scholarship have long emphasized that humans are unique in possessing cumulative culture... rapid social learning... and other distinct characteristics!
What seems new [or stronger] in this work is the claim that we are already in a regime where culture is the primary driver... not just an important one... and that genetic evolution is becoming secondary in many respects!
Implications!
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Biomedical and public health policy: If culture shapes a lot of health outcomes, then investing in cultural systems, [education, institutions, social norms] may yield more return than focusing purely on genetic interventions!
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Inequality: Societies with weak cultural/institutional systems may lag more. Your well-being might depend more on your society... than your genes!!!
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Evolutionary biology: May need to revise notions of what counts as “adaptation” or what forms of selection are most important!
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Future Human Evolution: Perhaps less biological change and more social/institutional/technological change will define our species’ trajectory in greater detail!
My Take: How Much... I'll Buy It!
Overall, I think this is a useful and largely credible theory. It’s not radical in the sense of rejecting genes as irrelevant... rather it highlights a shift in what dominates adaptation in many contexts!
For many societies today, culture really does seem the major factor in health, reproduction and survival!
So yes, I think there’s a lot of explanatory power there!
However, I’m cautious about overgeneralizing... there will still be domains where genetic evolution matters strongly... especially in harsher environments... or over very long time scales!
Also, culture is not uniform... nor always beneficial... it can constrain adaptability... as well as enable it!
