Ecology

Schistosomiasis, one of the most common human parasitic diseases, is a global menace because of its high rates of infection and contribution to poverty. Over the past two decades, global campaigns using antiparasitic medication have been carried out to combat the scourge of the disease. In 2022, the World Health Organization released guidelines1 to further expand the scale of these mass-treatment campaigns, with the goal of eliminating schistosomiasis as a public-health problem by 2030. Although this strategy has yielded clear public-health benefits2, the following key question remains: what solutions can be devised to further combat schistosomiasis and forge a sustainable future? Writing in Nature, Rohr et al.3 identify an innovative and transdisciplinary solution to reduce cases of schistosomiasis.
Competing Interests
N.C.L. reports personal fees from the World Health Organization related to work on public-health guidelines for schistosomiasis. More

RESEARCH BRIEFINGS
12 July 2023

Extensive fieldwork reveals that island plants have similar functions to plants in other regions of the world, but that the island environment, along with biogeographical and evolutionary processes, filters the life-history characteristics and strategies of the plants, rendering the island flora functionally and ecologically distinct from others. More

A survey of 84 coral ecosystems at 25 locations across the Pacific, Atlantic and Indian ocean basins found plastic debris from human activities in almost all of them, both shallow and deep.The study team, led by marine biologist Hudson Pinheiro at the University of São Paulo, Brazil, set out to survey biodiversity on remote reefs, which the researchers expected to be pristine. But during their sampling, they noticed that “these places are not as pristine as we were thinking”, Pinheiro says. It turned out that 77 of the 84 ecosystems contained macroplastics — plastic items measuring 5 centimetres or more across. The researchers found that this type of plastic waste made up 88% of all human-generated rubbish on the reefs1.Much of the debris found in the more remote locations was discarded fishing gear — including nets, hooks and lines. In some places, the team found evidence of “ghost fishing”, in which discarded fishing nets become stuck in the reefs and continue to trap and kill fish.

An old shoe lodged among corals on a reef near the Philippines.Credit: Luiz A. Rocha, California Academy of Sciences

In non-reef marine ecosystems, artificial plastic waste is usually concentrated near the surface and consists mostly of consumer items. But reefs are different — Pinheiro and his colleagues found that deeper reefs contained more macroplastics than shallow ones. There could be several reasons for this: strong waves can carry plastic away from shallow reefs or push it to the depths, for example. And clean-up efforts to remove plastic happen mainly on shallow reefs.

Marine organisms live alongside waste plastic even at a depth of 130 metres.Credit: Luiz A. Rocha, California Academy of Sciences

The deeper reefs are home to abundant fish species, which might explain why fishing nets and gear dominate the litter in these ecosystems, the authors say. As fewer and fewer fish are found in shallower waters, deep-sea fishing is becoming more common, and the amount of refuse could reflect this. “The fishermen are needing to get further away from shore, to fish in deeper reefs because of the pollution and degradation of the shallow reefs,” says Pinheiro.

Fishing lines tangled in a 100-metre-deep reef in the western Pacific.Credit: Luiz A. Rocha, California Academy of Sciences

The plastic waste can damage coral ecosystems in a number of ways. Ropes and nets can get tangled up in coral and cause breakages when fishers try to retrieve them. Plastic debris can also harbour bacteria and other microorganisms that can damage the coral. “Other studies have associated the presence of plastics with coral disease,” says Pinheiro.

A plastic bag drifts around one of Oman’s coral reefs.Credit: Tane Sinclair-Taylor

With negotiations under way for the United Nations global plastics treaty to end plastic pollution, thought needs to be given to how this kind of deep-reef pollution can be eliminated. “We are not talking about going to a supermarket and you change a plastic bag for a paper bag, we’re talking about people that depend on catching their food,” says Pinheiro, who urges negotiators to consider discussing subsidies and other incentives to help fishers to use less plastic, or developing biodegradable materials that could help put an end to contamination of the deepest coral reefs. More

The European Reference Genome Atlas (ERGA) aims to coordinate the production of high-quality genome sequences that represent eukaryotic biodiversity in Europe. As part of the Earth BioGenome Project, it will foster the widespread use of genomic resources for biodiversity protection, restoration and conservation.
Competing Interests
The authors declare no competing interests. More

Powerful vested interests are threatening the adoption of the proposed European Union Nature Restoration Law. The law would require restoration measures to be in place on 20% of Europe’s land and sea area by 2030, and aims to make the continent’s rivers, agriculture, forests and cities more biodiverse and resilient. The European Commission calculates that between 8 (US$9) and 38 will be returned in ecosystem services for every euro invested in restoration.Voting to pass the law takes place this month in the European Parliament. Opponents are influenced by lobbyists in favour of intensive agriculture, fisheries and the forestry industry, who say that the law would cut jobs and undermine food and energy security (see, for example, go.nature.com/3nhboyr; go.nature.com/44bfn8o; go.nature.com/3reitid). The political debate mostly disregards the law’s importance for mitigating and adapting to climate change.Time is short. The scientific community must fend off opposition by publicly debunking misinformation from lobbyists. The EU cannot reconcile a failure to approve the law with its calls for developing countries to stop clearing their pristine lands. More

I am passionate about the environment and everything related to it. My career path has included entrepreneurship and software development. But my first entry into conservation work was at National Geographic, where I learnt how technology can help with tangible problems, such as tracking elephant migration.In 2018, I joined EarthRanger, a technology platform now owned by the Allen Institute for AI in Seattle, Washington. EarthRanger collects, integrates and displays data and combines them with field reports on everything from animal traps to landslides. The platform has nearly 100 hardware and software data sources, including acoustic sensors and vehicle trackers. Conservationists can see a map with a unified, real-time view of relevant data, from positions of collared wildlife to observations from rangers. Before EarthRanger, these data were recorded on paper or spread across databases.I oversee the platform and develop the software. I spend a lot of time in the field with our partners, which include more than 400 organizations. I work with teams that track animals, study ecosystems and promote human–wildlife coexistence.One of our founding partners is Save the Elephants, based in Samburu, Kenya. It tracks hundreds of elephants across Africa and uses EarthRanger to monitor their locations.In this picture, I’m at the Save the Elephants headquarters. I’m surrounded by the skulls and jaws of elephants that have died from both natural and unnatural causes. It’s a remarkable place to reflect. It reminds you of the magnitude and urgency of the problem we’re facing.One elephant dying is a tragedy, and local interventions are needed to prevent more deaths. Tens of thousands dying is an existential risk. Mitigating that risk requires coordinated actions across many communities, organizations and governments. More

A TEPCO representative measures radiation levels around the treated water storage tanks in 2018.Credit: Kimimasa Mayama/AFP via Getty

Despite concerns from several nations and international groups, Japan is pressing ahead with plans to release water contaminated by the 2011 meltdown of the Fukushima Daiichi nuclear power plant into the Pacific Ocean. Starting sometime this year and continuing for the next 30 years, Japan will slowly release treated water stored in tanks at the site into the ocean through a pipeline extending one kilometre from the coast. But just how safe is the water to the marine environment and humans across the Pacific region?How is the water contaminated?The power station exploded after a devastating earthquake and subsequent tsunami crippled the coastal plant, overheating the reactor cores. Since then, more than 1.3 million cubic metres of seawater have been sprayed onto the damaged cores to keep them from overheating, contaminating the water with 64 radioactive elements, known as radionuclides. Of greatest concern are those that could pose a threat to human health: carbon-14, iodine-131, caesium-137, strontium-90, cobalt-60 and hydrogen-3, also known as tritium.Some of these radionuclides have a relatively short half-life and would already have decayed in the 12 years since the disaster. But others take longer to decay; carbon-14, for example, has a half-life of more than 5,000 years.How are they treating the water?The contaminated water has been collected, treated to reduce the radioactive content and stored in more than 1,000 stainless steel tanks at the site. The power-station operator, Tokyo Electric Power Company (TEPCO), so far has used what it describes as an advanced liquid-processing system (ALPS) to treat the water. TEPCO says the water undergoes five processing stages of co-sedimentation, adsorption and physical filtration. The plan for disposing of the radioactive waste created in the ALPS process will be “gradually revealed as the decommissioning process progresses”, according to communication the Permanent Mission of Japan to the International Organizations in Vienna sent to the International Atomic Energy Agency (IAEA).The ALPS process removes enough of 62 of the 64 radionuclides to bring their concentration below Japan’s 2022 regulatory limits for water to be discharged into the environment. These limits are based on recommendations from the International Commission on Radiological Protection.But that process does not remove carbon-14 and tritium, so the treated water needs to be diluted further to less than one part per 100 parts of seawater. TEPCO says that the resulting concentration of tritium is around 1,500 becquerels (a measure of the radioactivity of a substance) per litre — around one-seventh of the World Health Organization’s guidelines for tritium in drinking water. The company suggests that the concentration of tritium will drop to background ocean levels within a few kilometres of the discharge site. The carbon-14 in the tanks is currently at concentrations of around 2% of the upper limit set by regulations, TEPCO says, and this will reduce further with the seawater dilution that takes place before the water is discharged.Jim Smith, an environmental scientist at the University of Portsmouth, UK, says the risk this poses to nations around the Pacific Ocean will probably be negligible. “I always hesitate to say zero, but close to zero,” he says. “The nearest Pacific island is about 2,000 kilometres away.” He argues that a greater risk is posed by keeping the treated water on-site. “The risk of another earthquake or a typhoon causing a leak of a tank is higher, and they’re running out of space.”Will radioactivity concentrate in fish?Nations such as South Korea have expressed concern that the treated water could have unexplored impacts on the ocean environment, and a delegation from the country visited the Fukushima site in May. Last year, the US National Association of Marine Laboratories in Herndon, Virginia, also voiced its opposition to the planned release, saying that there was “a lack of adequate and accurate scientific data supporting Japan’s assertion of safety”. The Philippine government has also called for Japan to reconsider releasing the water into the Pacific.“Have the people promoting this going forward — ALPS treatment of the water and then release into the ocean — demonstrated to our satisfaction that it will be safe for ocean health and human health?” asks Robert Richmond, marine biologist at the University of Hawaii at Manoa. “The answer is ‘no’.”Richmond is one of five scientists on a panel advising the Pacific Islands Forum, an intergovernmental organization made up of 18 Pacific nations including Australia, Fiji, Papua New Guinea and French Polynesia. The panel was convened to advise on whether the release of the treated water from Fukushima was safe both for the ocean and for those who depend on it. Richmond says they have reviewed all the data provided by TEPCO and the Japanese government, and visited the Fukushima site, but there are still some unanswered questions about tritium and carbon-14.Tritium is a β-radiation emitter — albeit a weak one — meaning that it emits ionizing radiation that can damage DNA. TEPCO says the concentrations of tritium in the treated water release a dose of ionizing radiation lower than that experienced by someone flying a round trip from New York to Tokyo.But human skin partly blocks ionizing radiation, Richmond says. “If you eat something that’s radioactively contaminated with β-emitters, your cells inside are being exposed.”TEPCO says fishing is not routinely conducted in an area within 3 kilometres of where the pipeline will discharge the water. But Richmond is concerned the tritium could concentrate in the food web as larger organisms eat smaller contaminated ones. “The concept of dilution as the solution to pollution has demonstrably been shown to be false,” Richmond says. “The very chemistry of dilution is undercut by the biology of the ocean.”Shigeyoshi Otosaka, an oceanographer and marine chemist at the Atmospheric and Ocean Research Institute of the University of Tokyo says that the organically bound form of tritium could accumulate in fish and marine organisms. He says international research is investigating the potential for such bioaccumulation of the radionuclides in marine life, and what has already happened in the waters around Fukushima after the accidental release of contaminated water during the tsunami. “I think it is important to evaluate the long-term environmental impact of these radionuclides,” Otosaka says.A spokesperson for TEPCO said that the company has been conducting tests in which marine organisms are raised in seawater containing ALPS-treated water. “We have confirmed that the tritium concentrations in the bodies of marine organisms reach equilibrium after a certain period of time and do not exceed the concentrations in the living environment,” the spokesperson said. The tritium concentrations then decrease over time once the organism is returned to untreated seawater.TEPCO will continue to compare the health of organisms reared in diluted treated water with those reared in untreated seawater.Has this been done before?Smith points out that releasing tritium-contaminated water is part of the usual operating procedure for nuclear power plants. He says that both the Heysham nuclear power station and Sellafield nuclear-fuel-processing plant in the United Kingdom release between 400 and 2,000 terabecquerels of tritium into the ocean each year. “Overall, because it’s such a weak β-emitter, it’s not really that radiotoxic,” Smith says.Otosaka says that is also the case in Japan: “More than 50 terabecquerel of tritium was discharged annually from each nuclear power plant in regular operation before the accident,” he says. TEPCO says that less than 22 terabecquerels of tritium will be released from the pipeline each year. “The release rate of the tritium … is well controllable,” Otosaka says.TEPCO says there will be continuous monitoring of sea life and sediments around the area, which will be done by TEPCO, the Japanese Nuclear Regulation Authority and the IAEA.The IAEA, which has been supervising the clean-up and management of Fukushima, is expected to release a final report on the site and the plan for the wastewater release later in June. More

With agriculture the main driver of the habitat loss and degradation that underpin the global biodiversity crisis1, governments worldwide have implemented policies to lessen farming’s impact on the environment. Meanwhile, landowners, organizations interested in the financing of biodiversity conservation and certain non-governmental groups, including conservation bodies, have been pushing for land-use changes that benefit nature.However, numerous studies show that some of today’s most popular conservation policies are doing little to help those species most affected by farming. What’s more, by reducing how much food is produced per unit area (yield), they are driving up food imports and thereby having an impact on wildlife overseas.One of us (I.B.) has advised seven UK secretaries of state for the environment over the past decade; the other (A.B.) has, for two decades, led empirical work investigating how to reconcile food production with biodiversity conservation. In our view, there are many reasons for the disconnect between the science and policy.Part of the problem is that, especially in Europe, the owners of the biggest, and often richest, farms stand to gain the most from current policies2. Thousands of influential individuals are lobbying to maintain the status quo in agricultural policy.
EU climate plan sacrifices carbon storage and biodiversity for bioenergy
A more fundamental and massively under-recognized problem is that both government policy and much academic debate have focused too narrowly on the local effects of a given approach, rather than on its overall (often long-distance) impacts. Indeed, this tendency to ignore downstream consequences — even as much better tools and data become available to track and quantify such impacts — is causing significant problems across a range of conservation and climate policies.It doesn’t have to be this way. Modelling approaches are now being developed so that the information that is already available can significantly improve decision-making around agriculture and the environment. Using the wealth of evidence from research to guide agricultural policy could better reconcile conservation with people’s need for food. It could also pave the way for the evidence-based decision-making that is urgently needed across a broad sweep of environmental challenges.In vogueIn response to the biodiversity crisis, the European Union, the United Kingdom, Japan, Mexico and other regions and countries are increasingly devoting resources to what seem to be environmentally friendlier ways to use land.Since it was created in the 1960s, the Common Agricultural Policy (CAP) has been the EU’s most expensive policy. More than one-fifth of the CAP budget — currently set at €56 billion (US$60 billion) a year — is available for ‘environmental improvement’, and most of that is funnelled into ‘land-sharing’ schemes.

A wildflower margin next to a harvested Dutch wheat field — an example of land sharing.Credit: Getty

Land sharing uses a variety of approaches to increase biodiversity in farmland. Interventions include reducing the use of pesticides and fertilizers, adopting more-diverse cropping regimes and creating small-scale habitats such as unsprayed field margins and small patches of woodland.Land sharing increases the populations of relatively common animals and plants, such as skylarks, field poppies and the more widespread butterflies. And highly targeted interventions can help some vulnerable species. But in the main, land sharing does little for those most specialized or threatened species that need large stretches of contiguous non-farmed habitat, such as the many birds, invertebrates, plants and fungi dependent on old-growth forest. In fact, farmland biodiversity has continued to decline under land-sharing policies, with the UK population of corn buntings (Emberiza calandra), for example, falling by 83% since the late 1960s3.What’s more, taking land out of agriculture without lowering food demand or raising yields elsewhere in a country increases the need for imports, which means more harm to biodiversity and natural habitats farther away4. Indeed, the EU’s crop imports in the 25 years up to 2014 generated more than 11 million hectares of habitat destruction5 — an area larger than Cuba — in some of the world’s most biodiverse ecosystems, including those in Brazil and Indonesia (see ‘Offshoring the problem’). In 2020, even the EU’s official auditors declared the CAP a failure in terms of its environmental policies (see go.nature.com/45sasew).

Source: Ref. 5

Besides land sharing, two approaches have been gaining popularity in recent years, but each brings similar problems.Some conservation groups and landowners have increasingly advocated for rewilding, in which large, contiguous areas of land are taken out of farming. Rewilding can benefit species that are locally vulnerable or endangered. For example, efforts to rewild 400 hectares at Ken Hill in eastern England have created a refuge for beavers, which have been extinct in the United Kingdom since the sixteenth century. Such rewilding initiatives are obviously of value to national biodiversity. However, assessments of the benefits rarely consider offshore damage. As with land sharing, unless people change their diets or eat less, or yields are increased in areas that are still farmed, the removal of land from productive agriculture will increase the demand for food imports, and so damage biodiversity elsewhere6.
Europe’s Green Deal offshores environmental damage to other nations
Organic farming has been around for longer. In the past few years, both the EU and Japan have committed to converting one-quarter of farmland to organic production by 20305 and 2050 (see go.nature.com/43qycet), respectively. Although some farmland species are likely to benefit from the removal of manufactured fertilizers and modern pesticides, the approach will do little to help those that require contiguous natural habitats. Furthermore, organic production drastically lowers yields. Sri Lanka’s recent food crisis has been attributed in large measure to the government’s (now abandoned) attempt to convert the country to organic farming (see go.nature.com/3p2kgfq). And estimates suggest that a wholesale switch to organic farming across England and Wales would cut food-calorie output by 40%7. Again, this would lead to greater demand for food imports, and so increase pressure on production and hence on biodiversity around the world.What the science saysFortunately, another approach could bring substantial benefit to both local and global biodiversity (see ‘Helping or harming nature?’). Land sparing involves lumping habitat patches together into larger blocks, alongside the adoption of lower-impact ways to boost yields in the areas that are still farmed. Together, these two actions can make space for better habitat protection locally without displacing production overseas.

Source: data from multiple studies; see ref. 9 for a review.

Choosing which areas to put aside for nature requires an understanding of the consequences of land-use change — for food production, but also for greenhouse-gas fluxes, hydrological regimes, access to recreation, the spread of pollutants and so on. But, in relation to biodiversity, larger habitat blocks — which are less affected by the drier, often windier and more variable conditions at the margins — can, for their size, hold larger populations of those species that favour more-natural habitats. The greater diversity of environments that arise in larger areas also supports a greater diversity of specialist species8.For areas that are still farmed, an array of techniques can help producers to raise crop and livestock yields sustainably. Options include providing animals in extensive grazing systems with greater access to improved pasture, water sources and modern veterinary care; using genomic screening and gene editing to accelerate animal and crop breeding; growing high-value crops such as salad vegetables and herbs in trays that are stacked vertically; using native plants to redistribute pests away from crops; and using ‘recirculating’ aquaculture systems to produce high-value products such as king prawns.Over the past decade or so, field studies in India, Ghana, Uganda, Kazakhstan, Mexico, Colombia, Brazil and Uruguay, as well as in Poland and the United Kingdom, have all concluded9 that (for the same overall food output), high-yield farming combined with land sparing results in larger populations of most wild species than does land sharing (see ‘Winners and losers’). These findings, across more than 2,000 species of bird, plant and insect, are especially pronounced for those species with narrow geographical distributions, which make them particularly vulnerable.

Source: data from multiple studies; see ref. 9 for a review.

Last year, a study that surveyed UK farmers to establish what actions they would take, for what payment, found that delivering the same biodiversity outcomes for birds through land sparing would cost the taxpayer just 48% of the cost under land sharing; the impact on domestic food production would also be 21% lower under land sparing10. Thus, for the same budget, sparing seems to provide much greater biodiversity gains than does sharing.Other research has shown that, in comparison to land sharing, a land-sparing approach can deliver significantly greater co-benefits, such as the removal and storage of greenhouse gases and the provision of recreational areas11. And calculations for the United Kingdom and Poland show that blended approaches, which combine spared land with shared farmland and high-productivity agricultural land, do even better in these countries than does pure sparing, and greatly outperform both current farming systems and pure sharing approaches9.Because sparing increases yields on the land still being farmed (and this is more easily achieved wherever there are big gaps between current and potential yields), these approaches can help to address food-security concerns10. Also, the need for both agricultural innovation and, in many areas, habitat restoration means that land sparing need not adversely affect rural employment12.Of course, yield increases do not inevitably lead to more land being available for conservation. Critics of land sparing point out that gains in yield could simply lead to rebound effects, with less land being taken out of farming than expected, or even to more land being converted to farmland because of the promise of greater profits13.

Aquaculture techniques can raise yields sustainably, such as at this prawn farm in La Cruz, Mexico.Credit: Susana Gonzalez/Bloomberg via Getty

The evidence suggests, however, that although individual food producers generally use yield-intensifying practices to boost their incomes, overall land use tends to decrease13. These benefits could be increased by policies and subsidies crafted to dampen rebound effects; farmers could be given support for innovation in exchange for reducing the area under cultivation. A reassessment of data for birds and trees in Ghana and India shows that sparing would still outperform sharing even when policies to limit rebound effects are not put in place9.A matter of focus So, given that land sparing could benefit more biodiversity at lower cost than can other strategies, and deliver an array of co-benefits, why is it not the dominant approach today?The influence of the ‘big farm’ lobby in maintaining the status quo in agricultural policy is one widely cited reason14. The chief approach to allocating subsidies — using flat-rate payments per hectare of shared land — disproportionately benefits the largest (and often richest) farms. As a result, in the United Kingdom, 12% of farms take 50% of all taxpayer subsidies, whereas half of all farms share just 10% of those subsidies2 (see ‘The devil is in the detail’).
The devil is in the detail

Subsidies are used to persuade landowners to make changes to benefit nature, but subsidy design determines how effective they are.
Flat-rate subsidies pay farmers a set amount per hectare for conservation. This common approach channels the majority of subsidies towards the largest, and often richest, farms. Such schemes also fail to incentivize farmers to do more than the minimum stipulated in policy documents and often penalize those who go further. For example, if UK farmers plant trees on their land (and do not fell them at least every ten years), that land is removed from the tax exemptions accorded to ‘productive’ farmland (see go.nature.com/468wrzb).
A better approach would be to pay rewards not for the amount of land farmers devote to ‘nature improvement’, but for the expected outcomes. For this, farmers would be free to propose actions to address a specific environmental problem and to state what payments they would accept in return. Modelling is then used to predict benefits. By comparing these expected outcomes with the costs required by each farmer, decision makers can choose those farms and actions that deliver the best value for money19.

In our view, however, a more fundamental and much less recognized problem confounds the application of scientific research to environmental policy — and not just in relation to agriculture.The ‘focusing illusion’15, proposed by the Nobel-prizewinning psychologist and economist Daniel Kahneman, is the psychological phenomenon that focusing on one effect of a change tends to diminish our perception of all the other possible effects of that change. The literature is replete with studies of the effects of a change in terms of a single (often local) measure: biodiversity or carbon storage, nitrogen pollution or flooding, food production or recreation. Fewer assessments exist of multiple outcomes or of system-wide impacts.Historically, part of the challenge has been a lack of data and understanding. Even studies considering the plural effects of a change in how land is used have often been locally or nationally focused, largely because the modelling work linking the change to broader economic and environmental effects hasn’t been available16.Global-trade modelling, however, is now enabling researchers to obtain a much fuller picture of the economic and environmental effects of both policy interventions and business investments17.
Food systems: seven priorities to end hunger and protect the planet
Over the past five years or so, there has also been more research aimed at designing tools that allow policymakers and other stakeholders to understand the wider consequences of a change in land use. As an example, one of us (I.B.) is involved in a project to examine the full effects of the UK government’s decision, in 2020, to fund substantial increases in national woodland cover to remove greenhouse gases18. The Natural Environment Valuation Online tool (www.leep.exeter.ac.uk/nevo), which will be used in this project, combines information from multiple disciplines to show decision makers how such a change in the way land is used will help to satisfy England and Wales’s net-zero-emissions commitments, benefit biodiversity, improve access to recreation and so on. The tool also shows the impact of changes in land use on domestic food production, which can then be linked to changes in land use and biodiversity globally.The goal of research on system-wide impacts should not be to obtain ever more detailed sources of information about all the possible effects of a proposed policy change. Rather, analyses should be extended to the point at which the costs of collecting and analysing more data begin to exceed the benefits of more-informed decision-making. Such interdisciplinary studies and approaches that focus on the needs of decision makers must become the norm.The stakes are too high for policymakers to continue to ignore the promise of land sparing when so much research demonstrates that it is a much more effective approach than many of the strategies being deployed. This issue has become even more urgent since last December, with the adoption of the Convention on Biological Diversity’s goal of protecting 30% of the planet’s land and oceans by 2030. Exactly how this 30% will be put aside (as large contiguous natural habitats or as a multitude of fragments), and how the world’s growing demand for food and other goods will be met from the unprotected remainder of Earth’s surface, will in large part determine the biodiversity consequences of this ambitious commitment.Yet the story about land sparing carries an even broader message: unless researchers and policymakers assess the overall, global effects of interventions aimed at addressing biodiversity loss, climate change and environmental degradation, poor decisions that are unsupported by the data will at best under-deliver, and at worst exacerbate these existential threats. More