Why Have Humans Gotten Shorter Since About 10,000 Years Ago, and What’s Currently Reversing It? — Here’s What Scientists Found

Before 10,000 years ago, humans are believed to have had bigger bodies and, on average, taller. This was a time when the primary lifestyle of most Homo sapiens around the world was hunting and gathering resources. They would scavenge and forage the food sources in their natural habitats, and when it was depleted, either via climate change or other environmental shifts, they would migrate to a new area.

However, when farming was discovered gradually over thousands of years, this lifestyle changed, but along with it was a trend of declining or stagnating height of humans. What exactly triggered this phenomenon? And why was it reversing now in the modern world? Let’s dive deeper into these questions and ideas in this article.

The Drop in Height After the Agricultural Shift

After people began farming, there has been a dramatic but gradual decrease in height over time. This is not universal, though, as some regions only stagnated, and some that were not affected at all, either because of their specific circumstances or the lack of fossil evidence to support a decrease in height claim.

However, in Europe and the Near East, research shows that early farmers’ stature declined or stagnated for a few thousand years. One possible explanation is the change in diet that came with the shift in lifestyle. When humans transitioned from hunter-gatherers into farmers, their food supply became more reliable, but it came with a cost or trade-off.

The nutrition of the food sources is thought to have decreased with the advent of farming. This is because hunter-gatherers have more variety, where they would hunt animals for meat but also forage wild plants, and then if their habitat was depleted, they would migrate to a new environment that could possibly have different types of resources.

However, for farmers, they are limited to the grains and seeds they know how to grow, or the animals that they have learned to tame and domesticate. Their food sources became more reliable, but the variability of nutrients like proteins, minerals, and vitamins declined. This is one of the possible reasons why people’s height started to trend downwards around this time. But since these changes are not universal, there may have been a lot of other factors that could have affected this trend.

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What Caused the Height Decrease

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Scientists believe that rather than just one primary reason, there may have been a multitude of factors that led humans to have declining height over many generations. One of the mentioned reasons above was the change of diet, and it is one of the most significant. Another would be the new lifestyle and living conditions associated with farming.

During our ancestors’ time, hunting and gathering, they had to do a lot of strenuous activities to survive. For example, they chased prey under the scorching heat of the sun for long distances, or vice versa, where they are the prey and had to avoid predators. Additionally, they lived in different environments like rocky mountains, woodlands, deserts, and icy regions, so their bodies had to be stronger, bigger, and taller to adapt.

However, with farming, they could stop the nomadic lifestyle and be more sedentary, where they would stay and live closer to their farms in order to tend to the crops and livestock. This could have reduced the evolutionary pressure to become taller, as they do not need to do the strenuous tasks anymore that previous generations had to do to survive.

Farming was still hard, but the work was repetitive and less physically demanding, holistically, compared to what a hunter-gatherer does on a daily basis. One more factor that could have affected height was their overall health as a society. Since farming made humans live closer together in one place with other people and animals, diseases spread quickly. This phenomenon could have influenced their average height as a group, but it is more likely that the different reasons all played roles, affecting the downward trend.

What’s Reversing the Trend?

Despite the declining or stagnating height of the human species, it has now been recorded to be in a reversal trend. We are now getting bigger, stronger, and taller again as a species. Although this is average, and not all groups across the world, it is still a fact that may have been influenced by factors related to our society’s technological advances.

In some places in Northern Europe, after 3000 BC, there had already been an increase in height in the population. But it is more observable now in the last 150 years. However, what exactly affects this trend, and why are we getting taller even more? One of the key differences was the change in diet. When humans transitioned from hunter-gatherers to farming, the variability of the nutrition in their food declined, but in modern times, we now have an abundance of resources more than ever.

Additionally, the improvement in health and living conditions may have played a big role, too. Before, the early farmers who began living together close to each other and to animals became more vulnerable to the spread of diseases. This may have affected their growth and overall health, but with recent medical advances, we are now less prone to these diseases or are better at dealing with them.

Moreover, the decrease in height may not be a negative feature but an adaptation in response to our environment and survival challenges. For example, during the time of the early farmers, it was common to have crop failures, and this could easily decrease the food supply they had. A smaller and shorter body may have been advantageous, as it would result in needing less energy and food to maintain and grow. But now that we have better living conditions and environment, it may not be as advantageous anymore, compared to a bigger, stronger, and taller body.

However, just like with the possible reasons for why people declined in height, the increase is most likely because of the combination of factors instead of just one.

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What This Tells Us About Human Biology and Growth

Why Are People So Much Taller Today Than Historically?

So, what does the dramatic but gradual decrease in height around 10,000 years ago, and the recent increases, tell us about human biology and growth? Well, it highlights just how flexible our bodies could be. It responds to the changes in our diet, environment, and overall living conditions or lifestyles.

Additionally, genes do matter, and they will dictate a big percentage of our height. But a big trend that involves a large group of the human population means there were other important factors like nutrition, vulnerability to diseases, and even workload that could lead to a reduction or an increase in selection pressure to become stronger, shorter, or taller.

Finally, it tells us that our growth potential still remains. Over a relatively short period compared to our overall history, humans have become taller again, so if our living conditions and environment affected us in this brief timeframe, what else could happen over the long run?

Author's Final Thoughts

Humans in certain regions across the world have become shorter after many generations, beginning around 10,000 years ago. One of the biggest reasons for this shift was our transition to farming from a hunting and gathering lifestyle. It changed our diet, nutrition in our food, vulnerability to the spread of diseases, and allowed us to be more sedentary.

The combinations of all these factors and effects of transition to farming may have been what caused the decline or stagnation of height in the human population. But the recent reversal of the trend could be attributed to the advances in medical technologies, better diet and nutrition in our food, and less vulnerability to environmental threats.

Though the drop in our height as a species may seem a setback, the fact that we have begun to reverse the trend in a short timeframe, relatively to the entirety of human evolution, means that with the right lifestyle and better living conditions, we still could grow. But the main takeaway here should be that our bodies are resilient and would adapt in response to our need for survival.

Read next: Why Have Humans Gotten Smaller and Weaker Since About 10,000 Years Ago, and What Factors Are Now Reversing That Trend? — Here’s What the Evidence Suggests

References & Further Reading

Marciniak, S., et al. (2022). An integrative skeletal and paleogenomic analysis of stature variation suggests relatively reduced health for early European farmers. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.2106743119

Larsen, C. S. (1995). Biological changes in human populations with agriculture. Annual Review of Anthropology. https://doi.org/10.1146/annurev.an.24.100195.001153

NCD Risk Factor Collaboration (NCD-RisC). (2016). A century of trends in adult human height. eLife. https://doi.org/10.7554/eLife.13410

Hatton, T. J. (2014). How have Europeans grown so tall? Oxford Economic Papers. https://doi.org/10.1093/oep/gpt030