The article from ScienceAlert titled "Earth Could Have Billions More People Than We Ever Realized,"
https://www.sciencealert.com/earth-could-have-billions-more-people-than-we-ever-realized
reports on a study suggesting that global population estimates might be significantly undercounting people, particularly in rural areas. The research, led by environmental engineer Josias Láng-Ritter from Aalto University and published in Nature Communications, argues that the grid-based method traditionally used to estimate populations—dividing the world into squares and assigning numbers based on census data—misses substantial numbers of rural inhabitants. By comparing official displacement figures from 307 dam projects across 35 countries with five major population datasets, the study found discrepancies indicating that rural populations might have been underestimated by 53 percent to 84 percent between 1975 and 2010. Given that rural areas account for about 43 percent of the current global population (estimated at just over 8 billion), this could mean billions more people exist than previously thought, potentially pushing the true figure well beyond the UN's 8.2 billion estimate.
The researchers highlight that rural areas often lack granular data—census efforts, health records, and infrastructure mapping are less robust compared to urban zones. This gap could skew global datasets used in thousands of studies and policy decisions. Láng-Ritter suggests the findings have "far-reaching consequences," particularly for resource allocation like healthcare and transportation, where rural needs might be underrepresented. The study doesn't provide a new total population estimate but calls for improved censuses and alternative counting methods to refine our understanding.
The study's methodology—cross-referencing dam displacement data with population estimates—offers a concrete way to test the accuracy of global datasets. Dam projects often require precise counts of displaced people for compensation, providing a rare ground-truth check against broader estimates. Rural undercounting makes sense given logistical challenges—remote areas are harder to survey, and some populations (e.g., nomadic groups or those in conflict zones) might evade traditional censuses entirely. Historical examples, like India's census adjustments or China's hukou system gaps, show undercounts happen. If true, this could reshape how we view resource distribution, environmental strain, and even projections for population growth, which the UN forecasts to peak at 10.4 billion by the 2080s. It aligns with a broader trend of questioning data reliability.
But the study's sample—307 dam projects in 35 countries—might not generalise globally. Dam-affected areas could differ systematically from other rural regions (e.g., higher density near water sources), inflating the perceived undercount. Without a wider dataset, the "billions more" claim feels speculative. The leap to "billions" feels like a rhetorical flourish to grab attention, especially when juxtaposed with Elon Musk's underpopulation worries.