The global food system is more productive than ever, but it's pushing natural systems out of balance in the extreme. Can science help farmers produce the food we need in a more sustainable way?

This is despite the study confirming that almost eleven times more carbon credits were issued from the REDD+ (Reduced Emissions from Deforestation and Degradation) voluntary carbon market than was justified.

Tropical forests are an invaluable global asset under increasing threat, and carbon markets have the potential to contribute substantial funds to their protection.

The researchers say future projects must ensure the claimed impacts reflect real reductions in deforestation: the REDD+ carbon credit market should not be abandoned, but far fewer credits should be issued, at a higher price.

Over the last two decades the voluntary carbon market - through which people can buy carbon credits to offset their carbon emissions - has boomed and almost bust. REDD+ schemes use funds from the sale of carbon credits to protect existing forests, but their valuation methods have come under heavy scrutiny leading to a crisis of confidence in the market.

The new study reveals that nine high‑issuing REDD+ projects accounted for much of the over‑crediting, skewing both market value and public perception. The researchers say that these ‘bad credits’ are not necessarily reflective of bad forest conservation projects.

The synthesis of six independent evaluations of the effectiveness of 44 REDD+ projects, representing almost half of the projects producing REDD+ carbon credits by 2020 - found that four in five projects successfully protected forests.

The report is published today in the journal Nature Communications.

“We found that many REDD+ projects were at far lower risk of deforestation than anticipated by project-led evaluations. Credits were issued based on predictions that these forests were at imminent risk of deforestation, but in reality this risk was often lower,” said Dr Tom Swinfield, a researcher in the University of Cambridge’s Department of Zoology and first author of the study.

He added: “It’s vital that future forest carbon credits accurately represent their benefits for these schemes to be a meaningful solution to deforestation.”

“A key take-home message is that ‘bad credits’ do not necessarily mean ‘bad projects’. Many projects have successfully slowed deforestation, even if more credits were sold than are justified,” said Professor Julia Jones at Bangor University, a co-author of the study.

She added: “The over-crediting scandal in the voluntary carbon market has left many with the unhelpful impression that anything to do with funding tropical forest conservation through carbon finance is a bit dodgy. It is important to set the record straight, as forest conservation is so vital to tackling climate change.”

How are carbon credits generated?

REDD+ schemes generate carbon credits by investing in the protection of the world’s most important forests, from the Congo to the Amazon basin. Credits represent the carbon that is no longer released through deforestation as a result. Organisations and individuals can then offset their own carbon footprint by buying credits equivalent to a given quantity of emissions.

Carbon credits are generated by comparing the anticipated deforestation in a region before protection, with the projected deforestation once areas of forest are protected through a REDD+ project. This depends on accurately selecting other, unprotected areas of forest against which robust comparisons can be made.

The problem many independent evaluators have discovered is that the comparison areas chosen by crediting agencies were often more exposed to deforestation than project areas would have been, so too many credits have been issued.

An evolving market

The value of the carbon market has plummeted to only around one quarter of its 2022 US $2 billion high, following widespread evidence that carbon credits were oversold.

Although the first generation of REDD+ methodologies has largely been phased out, the next generation has yet to be fully implemented - with major delays perhaps driven by concerns about getting the system right.

The researchers say to avoid over-crediting, future REDD+ projects must draw on more representative reference forests to better assess the true contribution of projects to forest protection.

Several improvements - such as using independent data providers to remove any bias in valuing credits - are already helping to make these credits more robust, but researchers say retrospective checking of project performance is also essential.

“This study confirms concerns widespread over‑crediting in the carbon market. But despite the challenges, carbon markets remain one of the few mechanisms we have to protect tropical forests while giving organisations and individuals the chance to compensate for their emissions,” said Swinfield.

Reference: Swinfield, T. et al: ‘Learning lessons from over-crediting to ensure additionality in forest carbon credits.’ Nature Communications, April 2026.

A major analysis led by the University of Cambridge has found that many REDD+ projects achieved meaningful reductions in forest loss - offering real environmental benefits.

It’s vital that future forest carbon credits accurately represent their benefits for these schemes to be a meaningful solution to deforestation.Tom SwinfieldTom SwinfieldForest conservation project in Indonesia

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The presence of malaria affected where human populations lived across sub-Saharan Africa between 74,000 and around 5,000 years ago, a new study has found.

Over tens of thousands of years, the presence of this disease shaped how human populations met and mixed - allowing genes to be exchanged, and helping create the population structure seen in humans today.

The findings suggest that infectious disease was not simply a challenge early humans faced: it was a fundamental factor shaping the course of human evolution.

The researchers say malaria may have driven populations away from high-risk environments and separated them across the landscape, or it may have caused high death rates in specific areas.

Increasing evidence suggests that modern humans emerged through interactions between populations living in different parts of Africa, rather than from a single birthplace. Until now, however, most explanations for how those populations were distributed across the continent have focused on climate alone. The new research shows that disease - specifically malaria - also played a crucial role.

The results are published today in the journal Science Advances.

To reach their results, the team started with present-day distribution maps of Africa’s main malaria‑transmitting mosquito species. Then they used climate models to reconstruct how the ranges of these mosquitoes shifted over the past 74,000 years, alongside estimates of likely malaria transmission intensity. Finally, they compared these results with archaeological maps of ancient human settlements, and looked at where and when humans and malaria potentially overlapped.

“We estimated the risk of malaria transmission across sub-Saharan Africa over the past 74,000 years, and found that ancient humans were not living in high-risk areas for the majority of this time,” said Dr Margherita Colucci in the University of Cambridge’s Department of Zoology, first author of the study.

Colucci, who is also a researcher at the Max Planck Institute of Geoanthropology, added: “Our results indicate that ancient human populations strongly avoided, or were unable to survive in, areas with high malaria transmission risk. The effects of these choices shaped human demography for the majority of the last 74,000 years, and likely much earlier.”

“By fragmenting human societies across the landscape, malaria contributed to the population structure we see today. Our study suggests that climate and physical barriers were not the only forces shaping where human populations could live,” said Professor Andrea Manica in the University of Cambridge’s Department of Zoology, a co-senior author of the study.

The researchers found an increasing geographic overlap between human populations and malaria-carrying mosquitoes after around 15,000 years ago, beginning in West Africa. This coincides with the appearance of a human genetic mutation that gave rise to sickle-cell anaemia - and also provides partial protection against malaria.

Until now, the emergence of infectious diseases affecting human populations was thought to be linked with the domestication of crops and the transition away from a hunter-gatherer lifestyle, thought to have begun around 8,000-7,000 years ago.

Scientists have struggled to investigate the impact of disease on humanity’s early history due to a lack of direct evidence. The oldest ancient pathogen DNA, for example, is only around 10,000 years old, with the majority only from the last 2-3,000 years. In this study, the researchers used novel methods combining multiple lines of evidence that allowed them to reach much further back into the past.

74,000 years ago is a common time point for researchers to stop at when looking into the past. It coincides with the Toba supervolcano eruption - the largest known explosive eruption in human history.

“Disease has rarely been considered a major factor shaping the earliest prehistory of our species, and without ancient DNA from these periods it has been difficult to test. Our research changes that, and provides a new framework for exploring the role of disease in deep human history,” said Professor Eleanor Scerri at the Max Planck Institute of Geoanthropology, also a senior author of the study.

This research was funded by the Max Planck Institute of Geoanthropology.

Reference: Colucci, M. et al: ‘Malaria shaped human spatial organization for the past 74 thousand years'. Science Advances, April 2026. DOI: 10.1126/sciadv.aea2316

Adapted from a press release by the Max Planck Institute of Geoanthropology.

A new study suggests that malaria influenced where early humans lived in sub-Saharan Africa between around 74,000 and 5,000 years ago, fragmenting populations and influencing patterns of genetic exchange long before recorded history.

By fragmenting human societies across the landscape, malaria contributed to the population structure we see today.Andrea ManicaMartin and Ondrej PelanekSub-Saharan landscape

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Professor Mark Brown has devoted decades to defending pollinators from disease, pesticides and parasites.

Lowland peatlands, such as the East Anglian Fens and Somerset Levels, are rich in carbon and have been prized for their ability to support productive agriculture. Since the 1600s, some 90% of UK lowland peat has been drained to this end. This peatland also contributes an estimated 4% to the UK's total greenhouse gas emissions. But by using wetland-adapted crops and machinery, soil can be farmed in a wetter state, helping to reduce peatland emissions while remaining economically productive and potentially benefitting nature.

In a new study published in the journal Ecological Solutions and Evidence, researchers have found that bird numbers in paludiculture sites are three times higher than on drained grasslands, and match those of natural wetlands. They surveyed bird communities in natural wetlands, paludiculture sites growing bulrush (Typha), and drained, grazed grasslands in the Netherlands. 

Birds that are wetland specialists including Reed Warbler, Reed Bunting, and Sedge Warbler were recorded alongside typical grassland bird species - creating a unique and diverse bird community. The paludiculture sites also contained several bird species of European or global conservation concern, namely Eurasian Oystercatcher, Meadow Pipit, and Eurasian Coot. 

Although paludiculture does not replicate natural wetlands, the findings show it can function as an important habitat within wetland-grassland landscapes. This could provide more spaces for wetland specialist species if cutting and harvesting are timed to minimise disturbance during the breeding season.

Dr Catherine Waite in the University of Cambridge's Department of Zoology and co-lead author of the study, said: “As pressures on land continue to grow, research like this provides vital insight into how different land management choices affect nature. This evidence is key to informing local and landscape level management decisions that balance environmental and human needs.”

Dr Joshua Copping, an RSPB Conservation Scientist and co-lead author, said: “We know that paludiculture can reduce greenhouse gas emissions associated with farming on peat, but our findings show its potential for wildlife too. Farmed wetlands support bird communities simply not found on drained grasslands. As the sector develops, paludiculture could help deliver a just transition for farmers who wish to continue farming while contributing to a nature-rich landscape.”

Paludiculture could aid in the reduction of land use emissions from peatland, thereby contributing to the Net Zero ambition. This approach offers a way to continue productive farming while providing climate and nature benefits, potentially serving as a viable alternative to full peatland restoration in some areas. Paludiculture could also support food and fibre production, delivering social and economic value alongside environmental gains.

Unlocking paludiculture’s potential will require investment, advisory support, and strong markets for wetland crops. A project led by the Farming and Wildlife Advisory Group (FWAG) South West, in collaboration with the RSPB, is developing best practice for establishing and managing bulrush crops, including trials at RSPB Greylake, Somerset. Funded by Natural England’s Paludiculture Exploration Fund, this project is also testing whether bulrush can help remove excess nutrients from surrounding farmland, to improve wetland condition.

Alice Groom, RSPB Head of Sustainable Land Use Policy, who was not involved in this study, said: “To deliver nature recovery, reduce emissions, and support farm businesses, we must explore techniques like paludiculture. Drained peatlands are degrading fast, and we are running out of time to rely on current methods. Combined with wetland restoration, re-wetting peat through paludiculture offers a path to a more resilient farming future while tackling the climate and nature crises.”

Will Barnard, FWAG South West, who was not involved in this study, said: “As an entirely new agricultural sector within the UK, paludiculture inevitably requires vision and external support. If we can harness the boundless energy and innovation of the farming sector, it offers the rare opportunity to blend real commercial growth with lowering our environmental footprint and helping nature.”

The team says that with the right policy support, investment, and continued research, wetter farming could play a key role in creating nature-positive, climate-resilient landscapes while supporting communities and farmers through a just transition.

Reference: Copping, J.P. et al: 'Typha-based paludiculture offers potential for greater bird species abundance and diversity than drained agricultural grassland.' Ecological Solutions and Evidence, Feb 2026. DOI: 10.1002/2688-8319.70169

Adapted from a press release by the RSPB.

Research led by the University of Cambridge and the RSPB shows that farming wetland-adapted crops on wetter peat - known as paludiculture - can support richer and more diverse bird communities than drained grassland.

This evidence is key to informing local and landscape level management decisions that balance environmental and human needs.Catherine WaiteBen Andrew rspb-imagesReed bunting, Emberiza schoeniclus, perched in reedbed.

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