Technological advances have brought higher crop yields and with that, saved over 16 million hectares of wild habitat worldwide. Thanks to this swathe of protected land, thousands of species of animals and plants have dodged extinction, and several billion tons of carbon dioxide has remained locked in the earth.

These estimates, from a new PNAS study, strengthen the argument for agricultural ‘land-sparing’ as a way to both conserve nature, and still produce enough food to feed the world.

Since the 1960s, international food research agencies such as CGIAR have been developing crops that are drought-resistant, pest-resistant, and able to produce more nutrients. Their primary goal has been to boost farmer incomes and alleviate food insecurity. Today, dozens of more productive crop varieties are now grown across 440 million hectares of farmland in developing countries—covering about two-thirds of the total land area where those crops are produced.

A decades-old theory called the ‘Borlaug Hypothesis’ suggests that such yield-boosting agricultural innovation could play a significant double role in limiting cropland expansion and curbing deforestation. Yet despite this, there has been relatively little investigation of this idea.

That question is what drew the researchers in, and with the help of a specially-devised model, they intended to investigate. Their model incorporated high resolution satellite data on global crop production and coverage, and also factored in productivity estimates associated with newer generations of higher-yielding crops. With this data, the researchers ran a complex simulation that allowed them to model the face of global agriculture with these crop improvements, across a period spanning from 1961 to 2015. The model also allowed them to exclude the effect of higher-yielding crops, to see on the other hand, what world agriculture would look like without such agricultural innovation.

Without high-yielding crops, we would be millions of hectares deeper into wild habitat than we currently are, the model confirmed. Not only have they brought 226 million metric tons of additional crops, but had we not developed these more productive varieties, farms would have consumed an additional 16 million hectares of wild land worldwide.

These land savings have also brought big benefits for biodiversity—particularly for 1,043 species of plants and animals that rely on the saved land to survive. The researchers calculated that if the 16 million hectares of saved land had instead been consumed by farms, these species—including 103 species of amphibians, 47 mammal species, and 25 reptiles, but mainly plants—would have been threatened with extinction.

The benefits continued to mount up in the model: the avoided land use from crop improvements has also avoided the release of more than 5 billion metric tons of CO2 equivalent that are stored in soils, the researchers say—greenhouse gas emissions that would have been let loose had the land been stripped to make way for farms.

Higher-yielding crops can save land by producing more per hectare and so limiting the need for farm expansion, and also by reducing a crop’s price, which in turn reduces the incentive to convert more land into crops. The dynamic doesn’t always play out this way. In some locations, increased yields in fact drove cropland expansion, which also released more emissions. This was due to unique market dynamics in those locations where higher crop availability drove higher prices, a feature that was revealed by the higher resolution satellite data the researchers incorporated in their study.

But overall, a general trend was clear: “At the global level, historical crop productivity improvements since the 1960s resulted in less cropland expansion and potentially saved thousands of threatened plant and animal species from extinction,” says Uris Baldos, research associate professor of agricultural economics at Purdue University, and lead author on the new study.

Interestingly, the results revealed that most of these benefits arose from specific hotspots around the world. High-yielding crop innovations have historically been focused in lower- and middle-income countries that also tend to have forest biomes and other ecosystems that are rich in biodiversity and have large carbon stores. In fact, 80% of the avoided plant extinction losses overlapped with biodiversity hotspots the researchers had identified in their model.

And, most of the avoided land-use emissions were linked to saved land in Southeast Asia and sub-Saharan Africa, where there are dense forests. Potentially, this points to places where land-sparing agricultural innovations could have uniquely strong climate and nature benefits going into the future.

The takeaway, as the researchers see it: decades of sustained investment in science and innovation have spared vast tracts of land from agriculture’s reach. “We need continuous growth in agricultural productivity to ensure food security and to reduce agriculture’s environmental impacts,” Baldos says. Heading into a decade where biodiversity and climate look to be increasingly fragile, the question now is, can we maintain this crucial funding and its trail of nature-saving innovation?

Baldos et. al. “Adoption of improved crop varieties limited biodiversity losses, terrestrial carbon emissions, and cropland expansion in the tropics.” PNAS. 2025.