Humans haven't stopped evolving
Claims that human evolution has “stopped” are challenged by examples ranging from lactose tolerance and disease resistance to fertility patterns shaped by modern contraception and culture. Commenters argue that while medicine and technology have changed or softened many traditional selection pressures, they have also introduced new ones, especially around immunity, social behavior, and reproductive choices. The consensus is that human evolution continues—often rapidly—but along different dimensions than in the past, and with ethically uncomfortable implications.
Perception that Human Evolution “Stopped”
- Many commenters find the article’s premise obvious: evolution never stops while reproduction and variation exist.
- Some note a widespread lay belief that humans are “done” evolving, often due to misunderstandings of “survival of the fittest.”
- Others criticize the article’s framing as clickbait or PR “slop,” saying it presents a non-surprising result as revelatory.
Timescales, Mechanisms, and Evidence
- Several point out evolution acts over many generations, making changes hard to see over decades but visible over thousands of years.
- Examples raised:
- Lactase persistence and lactose tolerance as recent adaptations.
- Skin pigmentation loss in populations that left Africa.
- Immune-related genes (MHC) showing clear signatures of continuous selection.
- Sickle-cell trait frequencies changing with malaria exposure.
- High-altitude and sea-diving adaptations (e.g., Tibetans, Bajau) mentioned.
- Debate over a quoted claim that humans have had “no biological change in 40–50k years”: some defend it as referring to broad anatomy; others call it plainly wrong.
Role of Technology, Medicine, and Modern Society
- One camp argues technology reduces classical selection pressures (disease, climate, food scarcity), allowing more “unfit” genotypes to survive.
- Others counter that this merely shifts selection to new traits: social status, risk-taking, cultural fit, ability to navigate modern environments.
- Modern medicine may let otherwise lethal mutations persist, but evolution continues as long as there is variation and differential reproduction.
Fertility, Culture, and Memes
- Declining fertility rates are seen as a strong new selection pressure: traits (genetic or cultural) promoting childbearing will spread.
- Reliable birth control is highlighted as a major shift: sex no longer guarantees reproduction, so selection may favor other drives to have children.
- Some suggest cultural “memes” (values, religiosity, pronatal norms) may be selected even faster than genes.
- There’s discussion of highly fertile traditionalist religious minorities potentially growing in relative share.
Violence, Environment, and “Better” Humans
- Multiple comments stress evolution is not moral progress: traits that increase reproduction can be socially harmful or environmentally destructive.
- Humans may be “successful” precisely because exploitation and intra-species harm historically improved survival and reproduction.
- Long-term success is questioned given rapid environmental degradation; whether our current trajectory is evolutionarily sustainable is left open.
Sexual and Social Selection
- Mate choice is emphasized as a major evolutionary driver, not just survival.
- Several speculate that intelligence, artistic ability, and political skill may have been amplified through sexual selection and status competition.
- Others note that modern selection might favor traits we don’t necessarily value (e.g., lower conscientiousness if it correlates with higher fertility).
Definitions and Edge Cases
- Confusion between genetic drift and natural selection is debated: some incorrectly claim drift “is not evolution,” others correct that any heritable frequency change counts as evolution.
- Discussion of “unchanged” species (e.g., sharks, crocodiles) suggests they likely still evolve but sit near local optima under stable conditions.
- Some argue that in principle evolution could nearly stall if a society equalized reproductive chances completely, but others see this as practically unattainable.