News

The metals have previously been shown to damage the health of pollinators, which ingest them in nectar as they feed, leading to reduced population sizes and death. Even low nectar metal levels can have long-term effects, by affecting bees’ learning and memory - which impacts their foraging ability.

Researchers have found that common plants including white clover and bindweed, which are vital forage for pollinators in cities, can accumulate arsenic, cadmium, chromium and lead from contaminated soils.

Metal contamination is an issue in the soils of cities worldwide, with the level of contamination usually increasing with the age of a city. The metals come from a huge range of sources including cement dust and mining.

The researchers say soils in cities should be tested for metals before sowing wildflowers and if necessary, polluted areas should be cleaned up before new wildflower habitats are established.

The study highlights the importance of growing the right species of wildflowers to suit the soil conditions. 

Reducing the risk of metal exposure is critical for the success of urban pollinator conservation schemes. The researchers say it is important to manage wildflower species that self-seed on contaminated urban land, for example by frequent mowing to limit flowering - which reduces the transfer of metals from the soil to the bees.

The results are published today in the journal Ecology and Evolution. 

Dr Sarah Scott in the University of Cambridge’s Department of Zoology and first author of the report, said: “It’s really important to have wildflowers as a food source for the bees, and our results should not discourage people from planting wildflowers in towns and cities.

“We hope this study will raise awareness that soil health is also important for bee health. Before planting wildflowers in urban areas to attract bees and other pollinators, it’s important to consider the history of the land and what might be in the soil – and if necessary find out whether there’s a local soil testing and cleanup service available first.”

The study was carried out in the post-industrial US city of Cleveland, Ohio, which has over 33,700 vacant lots left as people have moved away from the area. In the past, iron and steel production, oil refining and car manufacturing went on there. But any land that was previously the site of human activity may be contaminated with traces of metals.

To get their results, the researchers extracted nectar from a range of self-seeded flowering plants that commonly attract pollinating insects, found growing on disused land across the city. They tested this for the presence of arsenic, cadmium, chromium and lead. Lead was consistently found at the highest concentrations, reflecting the state of the soils in the city.

The researchers found that different species of plant accumulate different amounts, and types, of the metals. Overall, the bright blue-flowered chicory plant (Cichorium intybus) accumulated the largest total metal concentration, followed by white clover (Trifolium repens), wild carrot (Daucus carota) and bindweed (Convolvulus arvensis). These plants are all vital forage for pollinators in cities - including cities in the UK - providing a consistent supply of nectar across locations and seasons.

There is growing evidence that wild pollinator populations have dropped by over 50% in the last 50 years, caused primarily by changes in land use and management across the globe. Climate change and pesticide use also play a role; overall the primary cause of decline is the loss of flower-rich habitat.

Pollinators play a vital role in food production: many plants, including apple and tomato, require pollination in order to develop fruit. Natural ‘pollination services’ are estimated to add billions of dollars to global crop productivity. 

Scott said: “Climate change feels so overwhelming, but simply planting flowers in certain areas can help towards conserving pollinators, which is a realistic way for people to make a positive impact on the environment.”

The research was funded primarily by the USDA National Institute of Food and Agriculture.

Reference 
Scott, S.B.& Gardiner, M.M.: ‘Trace metals in nectar of important urban pollinator forage plants: A direct exposure risk to pollinators and nectar-feeding animals in cities.’ Ecology and Evolution, April 2025.  DOI: 10.1002/ece3.71238
 

Wildflowers growing on land previously used for buildings and factories can accumulate lead, arsenic and other metal contaminants from the soil, which are consumed by pollinators as they feed, a new study has found.

Our results should not discourage people from planting wildflowers in towns and cities. But.. it’s important to consider the history of the land and what might be in the soil."Sarah ScottSarah ScottChicory growing in a vacant lot

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Now in its eighth year, the Fellowship provides financial support for a postdoctoral placement of one to two years at a world-class research institution.

The funding equips scientists to apply their knowledge to a new field of study with the goal of accelerating discoveries, and to develop their leadership potential.

Dr Poppy Oldroyd, a 2025 Schmidt Science Fellow from the Department of Engineering, plans to pioneer a new frontier in understanding brain communication through optical measurements, ultimately advancing treatments for memory-related diseases.

The human brain communicates through intricate networks of neurons, crucial for learning and memory. However, how these neural conversations translate into memory formation remains a mystery in neuroscience. Oldroyd’s research aims to use light-based tools, like advanced optogenetics, to explore these pathways in detail. By uncovering how specific brain circuits contribute to learning and memory, this research could revolutionise our understanding of these essential brain functions. 

Ultimately, this knowledge may enhance our comprehension of memory-related disorders like Alzheimer’s disease and epilepsy.

Dr Matthew McLouglin, a 2025 Schmidt Science Fellow from the Cambridge Stem Cell Institute, plans to develop tools to study how our cells age in real time. This will help us understand why we age and how we might promote healthy aging to improve quality of life in the elderly.

Our DNA is organised into structures called chromosomes. Each chromosome has a protective cap, the ‘telomere’, which is partially lost with each cell division. In old age, cells cannot function properly due to the loss of telomeres, increasing the risk of age-related diseases such as cancer and dementia. McLoughlin will use cutting-edge imaging technology to track the loss of telomeres over time, understanding how telomeres are lost and why this stops cells from functioning.

Oldroyd and McLoughlin join a community of 209 Schmidt Science Fellows from nearly 40 countries who are leaders in interdisciplinary science.

“Philanthropic funding of scientific research, and especially support of early-career researchers, has never been more important,” said Wendy Schmidt, who co-founded Schmidt Science Fellows with her husband, Eric.

“By providing Schmidt Science Fellows with support, community, and freedom to work across disciplines and gain new insights, we hope they’ll tackle some of the world’s most vexing challenges, achieve breakthroughs and help create a healthier, more resilient world for all.”

Established in 2017, Schmidt Science Fellows is a programme of Schmidt Sciences delivered in partnership with the Rhodes Trust.

The 2025 Fellows represent 15 nationalities, including researchers from Jordan and the United Arab Emirates for the first time in the programme’s history.

This year’s cohort will work on a range of problems from cancer treatment to quantum technologies to sustainability.

Alongside their research Placement, Fellows participate in a 12-month interdisciplinary Science Leadership Programme.

Each year, Schmidt Science Fellows works in partnership with more than 100 universities to identify candidates for the Fellowship.

Nominees are selected via an application process that includes an academic review with panels of experts in their original disciplines and final interviews with a multidisciplinary panel of scientists and private sector leaders.

“The Schmidt Science Fellows Program is cultivating a dynamic global community of remarkable scientists and champions of interdisciplinary research,” said Stu Feldman, Chief Scientist at Schmidt Sciences.

“Their work exemplifies Schmidt Sciences’ commitment to support pioneering approaches that will drive the next era of discovery and innovation.”

The 2025 Schmidt Science Fellows represent 27 nominating universities, including, for the first time, McGill University in Canada, RWTH Aachen University in Germany, Tecnológico de Monterrey in Mexico, University of California, Los Angeles in the US, and University of Groningen in the Netherlands.

Two University of Cambridge researchers are among the thirty-two early career researchers, tackling issues from improving food security to developing better medical implants, who have been announced as the 2025 Schmidt Science Fellows.

Schmidt Science FellowsPoppy Oldroyd (left) and Matthew McLoughlin (right)

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Yes

Cambridge researchers are looking at ways that AI can transform everything from drug discovery to Alzheimer's diagnoses to GP consultations.

We were delighted to welcome pupils from Warrington’s Lymm High School, Ipswich High School, The Charter School in North Dulwich, Rickmansworth School, Sutton Valance School in Maidstone as well as schools closer to home such as St Peter’s Huntingdon, Fenstanton Primary School, Barton Primary School, Impington Village College and St Andrews School in Soham. 

Running over two days (25/26 March 2025) and held in the Cambridge Sports Centre, students went on a great alien hunt with Dr Matt Bothwell from the Institute of Astronomy, stepped back in time to explore Must Farm with Department of Archaeology and the Cambridge Archaeological Unit as well as learning to disagree well with Dr Elizabeth Phillips from The Woolf Institute. 

Schools had a choice of workshops from a range of departments including, how to think like an engineer and making sustainable food with biotechnology with researchers from the Department of Chemical Engineering and Biotechnology, as well as the chance to get hands-on experience in the world of materials science and explore how properties of materials can be influenced by temperature at the Department of Materials Science and Metallurgy. 

The Department of Veterinary Medicine offered students the opportunity to find out what a career in veterinary medicine may look like with workshops on animal x-rays, how different professionals work together to treat animals in a veterinary hospital as well as meeting the departments horses and cows and learn how veterinarians diagnose and treat these large animals. 

Students also had the opportunity to learn about antibodies and our immune system with the MRC Toxicology Unit. The students learnt about the incredible job antibodies do defending our bodies against harmful invaders like bacteria and viruses. 

Alongside this, a maths trail, developed by Cambridgeshire County Council, guided students around the West Cambridge site whilst testing their maths skills with a number of problems to solve. 

Now in their third year, the Cambridge Festival schools days are offering students the opportunity to experience studying at Cambridge with a series of curriculum linked talks and hands on workshops.   

The Cambridge Festival runs from 19 March – 4 April and is a mixture of online, on-demand and in-person events covering all aspects of the world-leading research happening at Cambridge. The public have the chance to meet some of the researchers and thought-leaders working in some of the pioneering fields that will impact us all.

Over 500 KS2 and KS3 students from as far away as Warrington got the chance to experience studying at the University of Cambridge with a selection of lectures and workshops held as part of the Cambridge Festival. 

Students make antibody keychains during a workshop with the MRC Toxicology Unit

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Yes

A major review of over 67,000 animal species has found that while the natural world continues to face a biodiversity crisis, targeted conservation efforts are helping bring many species back from the brink of extinction.

Using advanced analysis based on full genome sequences, researchers from the University of Cambridge have found evidence that modern humans are the result of a genetic mixing event between two ancient populations that diverged around 1.5 million years ago. About 300,000 years ago, these groups came back together, with one group contributing 80% of the genetic makeup of modern humans and the other contributing 20%.

For the last two decades, the prevailing view in human evolutionary genetics has been that Homo sapiens first appeared in Africa around 200,000 to 300,000 years ago, and descended from a single lineage. However, these latest results, reported in the journal Nature Genetics, suggest a more complex story.

“The question of where we come from is one that has fascinated humans for centuries,” said first author Dr Trevor Cousins from Cambridge’s Department of Genetics. “For a long time, it’s been assumed that we evolved from a single continuous ancestral lineage, but the exact details of our origins are uncertain.”

“Our research shows clear signs that our evolutionary origins are more complex, involving different groups that developed separately for more than a million years, then came back to form the modern human species,” said co-author Professor Richard Durbin, also from the Department of Genetics.

While earlier research has already shown that Neanderthals and Denisovans – two now-extinct human relatives – interbred with Homo sapiens around 50,000 years ago, this new research suggests that long before those interactions – around 300,000 years ago – a much more substantial genetic mixing took place. Unlike Neanderthal DNA, which makes up roughly 2% of the genome of non-African modern humans, this ancient mixing event contributed as much as 10 times that amount and is found in all modern humans.

The team’s method relied on analysing modern human DNA, rather than extracting genetic material from ancient bones, and enabled them to infer the presence of ancestral populations that may have otherwise left no physical trace. The data used in the study is from the 1000 Genomes Project, a global initiative that sequenced DNA from populations across Africa, Asia, Europe, and the Americas.

The team developed a computational algorithm called cobraa that models how ancient human populations split apart and later merged back together. They tested the algorithm using simulated data and applied it to real human genetic data from the 1000 Genomes Project.

While the researchers were able to identify these two ancestral populations, they also identified some striking changes that happened after the two populations initially broke apart.

“Immediately after the two ancestral populations split, we see a severe bottleneck in one of them—suggesting it shrank to a very small size before slowly growing over a period of one million years,” said co-author Professor Aylwyn Scally, also from the Department of Genetics. “This population would later contribute about 80% of the genetic material of modern humans, and also seems to have been the ancestral population from which Neanderthals and Denisovans diverged.”

The study also found that genes inherited from the second population were often located away from regions of the genome linked to gene functions, suggesting that they may have been less compatible with the majority genetic background. This hints at a process known as purifying selection, where natural selection removes harmful mutations over time.

“However, some of the genes from the population which contributed a minority of our genetic material, particularly those related to brain function and neural processing, may have played a crucial role in human evolution,” said Cousins.

Beyond human ancestry, the researchers say their method could help to transform how scientists study the evolution of other species. In addition to their analysis of human evolutionary history, they applied the cobraa model to genetic data from bats, dolphins, chimpanzees, and gorillas, finding evidence of ancestral population structure in some but not all of these.

“What’s becoming clear is that the idea of species evolving in clean, distinct lineages is too simplistic,” said Cousins. “Interbreeding and genetic exchange have likely played a major role in the emergence of new species repeatedly across the animal kingdom.”

So who were our mysterious human ancestors? Fossil evidence suggests that species such as Homo erectus and Homo heidelbergensis lived both in Africa and other regions during this period, making them potential candidates for these ancestral populations, although more research (and perhaps more evidence) will be needed to identify which genetic ancestors corresponded to which fossil group.

Looking ahead, the team hopes to refine their model to account for more gradual genetic exchanges between populations, rather than sharp splits and reunions. They also plan to explore how their findings relate to other discoveries in anthropology, such as fossil evidence from Africa that suggests early humans may have been far more diverse than previously thought.

“The fact that we can reconstruct events from hundreds of thousands or millions of years ago just by looking at DNA today is astonishing,” said Scally. “And it tells us that our history is far richer and more complex than we imagined.”

The research was supported by Wellcome. Aylwyn Scally is a Fellow of Darwin College, Cambridge. Trevor Cousins is a member of Darwin College, Cambridge.

 

Reference:
Trevor Cousins, Aylwyn Scally & Richard Durbin. ‘A structured coalescent model reveals deep ancestral structure shared by all modern humans.’ Nature Genetics (2025). DOI: 10.1038/s41588-025-02117-1

Modern humans descended from not one, but at least two ancestral populations that drifted apart and later reconnected, long before modern humans spread across the globe.

Our history is far richer and more complex than we imaginedAylwyn ScallyJose A. Bernat Bacete via Getty ImagesPlaster reconstructions of the skulls of human ancestors

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Yes

Researchers studying British Labrador retrievers have identified multiple genes associated with canine obesity and shown that these genes are also associated with obesity in humans.  

The dog gene found to be most strongly associated with obesity in Labradors is called DENND1B. Humans also carry the DENND1B gene, and the researchers found that this gene is also linked with obesity in people.  

DENND1B was found to directly affect a brain pathway responsible for regulating the energy balance in the body, called the leptin melanocortin pathway.  

An additional four genes associated with canine obesity, but which exert a smaller effect than DENND1B, were also mapped directly onto human genes. 

“These genes are not immediately obvious targets for weight-loss drugs, because they control other key biological processes in the body that should not be interfered with.

But the results emphasise the importance of fundamental brain pathways in controlling appetite and body weight,” said Alyce McClellan in the University of Cambridge’s Department of Physiology, Development and Neuroscience, and joint first author of the report.  

“We found that dogs at high genetic risk of obesity were more interested in food,” said Natalie Wallis in the University of Cambridge’s Department of Physiology, Development and Neuroscience, and joint first author of the report.  

She added: “We measured how much dogs pestered their owners for food and whether they were fussy eaters. Dogs at high genetic risk of obesity showed signs of having higher appetite, as has also been shown for people at high genetic risk of obesity.”  

The study found that owners who strictly controlled their dogs’ diet and exercise managed to prevent even those with high genetic risk from becoming obese - but much more attention and effort was required.  

Similarly, people at high genetic risk of developing obesity will not necessarily become obese, if they follow a strict diet and exercise regime - but they are more prone to weight gain. 

As with human obesity, no single gene determined whether the dogs were prone to obesity; the net effect of multiple genetic variants determined whether dogs were at high or low risk. 

The results are published today in the journal 'Science'. 

“Studying the dogs showed us something really powerful: owners of slim dogs are not morally superior. The same is true of slim people. If you have a high genetic risk of obesity, then when there’s lots of food available you’re prone to overeating and gaining weight unless you put a huge effort into not doing so,” said Dr Eleanor Raffan, a researcher in the University of Cambridge’s Department of Physiology, Development and Neuroscience who led the study. 

She added: “By studying dogs we could measure their desire for food separately to the control owners exerted over their dog’s diet and exercise. In human studies, it’s harder to study how genetically driven appetite requires greater willpower to remain slim, as both are affecting the one person.” 

The current human obesity epidemic is mirrored by an obesity epidemic in dogs. About 40-60% of pet dogs are overweight or obese, which can lead to a range of health problems. 

Dogs are a good model for studying human obesity: they develop obesity through similar environmental influences as humans, and because dogs within any given breed have a high degree of genetic similarity, their genes can be more easily linked to disease. 

To get their results, the researchers recruited owners with pet dogs in which they measured body fat, scored ‘greediness’, and took a saliva sample for DNA. Then they analysed the genetics of each dog. By comparing the obesity status of the dog to its DNA, they could identify the genes linked to canine obesity. 
Dogs carrying the genetic variant most associated with obesity, DENND1B, had around 8% more body fat than those without it.  

The researchers then examined whether the genes they identified were relevant to human obesity. They looked at both large population-based studies, and at cohorts of patients with severe, early onset obesity where single genetic changes are suspected to cause the weight gain.  

The researchers say owners can keep their dogs distracted from constant hunger by spreading out each daily food ration, for example by using puzzle feeders or scattering the food around the garden so it takes longer to eat, or by choosing a more satisfying nutrient composition for their pets. 

Raffan said: “This work shows how similar dogs are to humans genetically. Studying the dogs meant we had reason to focus on this particular gene, which has led to a big advance in understanding how our own brain controls our eating behaviour and energy use.”  

The research was funded by Wellcome, the BBSRC, Dogs Trust, Morris Animal Foundation, MRC, France Genomique consortium, European Genomic Institute for Diabetes, French National Center for Precision Diabetic Medicine, Royal Society, NIHR, Botnar Foundation, Bernard Wolfe Health Neuroscience Endowment, Leducq Fondation, Kennel Club Charitable Trust. 

Reference 
Wallis, N.J. et al: ‘Canine genome-wide association study identifies DENND1B as an obesity gene in dogs and humans.’ Science, March 2025. DOI: 10.1126/science.ads2145  
 

Researchers at the University of Cambridge have discovered genes linked to obesity in both Labradors and humans. They say the effects can be over-ridden with a strict diet and exercise regime.

Dogs at high genetic risk of obesity showed signs of having higher appetite, as has also been shown for people at high genetic risk of obesity.Natalie WallisJames Barker on UnsplashLabrador licking nose

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The pledge, made in February 2020 by the UK’s nine leading game shooting and rural organisations, aimed to benefit wildlife and the environment and ensure a market for the healthiest game meat food products. 

But a Cambridge team, working with the University of the Highlands and Islands, has consistently shown that lead shot was not being phased out quickly enough to achieve a complete voluntary transition to non-toxic ammunition by 2025. In a final study, published today in the journal Conservation Evidence, the team concludes that the intended transition has failed.

The team has closely monitored the impact of the pledge every year since its introduction, recruiting expert volunteers to buy whole pheasants from butchers, game dealers and supermarkets across Britain and recover embedded shotgun pellets for analysis. 

In 2025, the study - called SHOT-SWITCH - found that of 171 pheasants found to contain shot, 99% had been killed with lead ammunition. 

This year, for the first time, the team also analysed shotgun pellets found in red grouse carcasses shot in the 2024/25 shooting season and on sale through butchers’ shops and online retailers. In all 78 grouse carcasses from which any shot was recovered, the shot was lead. 

“Many members of the shooting community had hoped that the voluntary pledge away from lead ammunition would avert the need for regulation. But the voluntary route has now been tested - with efforts made by many people - and it has not been successful,” said Professor Rhys Green in the University of Cambridge’s Department of Zoology and lead author of the report.

Eating game meat killed using lead shot will expose people unnecessarily to additional dietary lead. Lead is toxic to humans even in very small concentrations; the development of the nervous system in young and unborn children is especially sensitive to its effects. As a result, many food safety agencies now advise that young children and pregnant women should avoid, or minimise, eating game meat from animals killed using lead ammunition.

Discarded shot from hunting also poisons and kills many tens of thousands of the UK’s wild birds each year.

Despite proposing the voluntary change, many shooting organisations and some individual shooters do not support proposed regulatory restrictions on lead ammunition.

Green said: “Private individuals pay a lot of money to shoot pheasants on some private estates - and people don’t like to change their habits. It’s a bit like wearing car seatbelts, or not smoking in pubs. Despite the good reasons for doing these things, some people were strongly against using regulation to achieve those changes, which are now widely accepted as beneficial. The parallel with shooting game with lead shotgun ammunition is striking.” 

Danish shooters now say that the legal ban on lead introduced in Denmark around 30 years ago was justified. They say it has not reduced the practicality or popularity of their sport, and has increased its acceptability to wider society.

“Although a few large UK estates have managed to enforce non-lead ammunition on pheasant shoots, some have had to be quite draconian in order to do it, with the estate gamekeepers insisting on loading the guns for the shooters,” added Green.

In the 2020/21 and 2021/22 shooting seasons, over 99% of the pheasants studied were shot using lead ammunition. This figure dropped slightly to 94% in 2022/23 and 93% in 2023/24, with the remaining pheasants killed by ammunition made of steel or a metal called bismuth, before rising to 99% again in 2024/25.

Retail pressure

The researchers also checked up on a pledge made by Waitrose in 2019 to stop selling game killed with lead ammunition. 

They found that the retailer had been largely let down by suppliers, and that some of their shooters continued to shoot using lead despite making assurances to the contrary. As a result, Waitrose did not sell oven-ready pheasants at all between 2021 and 2023. It sold pheasants again in January 2024 and the 2024/25 season, but the researchers showed that the majority had been killed using lead shot.

In 2022 the National Game Dealers Association (NGDA), which buys game and sells it to the public and food retailers, also announced it would no longer sell game of any kind that had been shot using lead ammunition. But this pledge has since been withdrawn. The researchers bought 2024/25 season pheasants from three NGDA member businesses and found that all had been shot with lead ammunition.

Inside influence 

The researchers also analysed all articles relating to the voluntary transition published in the magazine of the UK’s largest shooting organisation, the British Association for Shooting and Conservation. They found that articles near the beginning of the five-year pledge communicated clear, frequent and positive messages about the effectiveness and practicality of non-lead shotgun ammunition.

But by 2023, mentions of the transition and encouragement to follow it had dropped dramatically. 

The upshot

At the request of the Defra Secretary of State, the UK Health & Safety Executive (HSE) has assessed the risks to the environment and human health posed by lead in shot and bullets. Its report, published in December 2024, proposes that the UK Government bans the use of lead shot and large calibre bullets for game shooting because of the risks they pose to the environment and health. This recommendation is currently under review by Defra ministers, with a response due in March 2025.

Steel shotgun pellets are a practical alternative to lead and can be used in the vast majority of shotguns, as can other safe lead-free alternatives. But the results of this study indicate UK hunters remain unwilling to make the switch voluntarily.

Since 2010, UK governments have preferred voluntary controls over regulation in many areas of environment and food policy and have suggested that regulation be used only as a last resort.

“Shooting organisations did a lot of questionnaire surveys when the pledge was introduced in 2020, and the results suggested many shooters thought the time had come to switch away from lead ammunition. Those responses stand in contrast to what we’ve actually measured for both pheasant and grouse,” said study co-author Dr Mark Taggart at the University of the Highlands and Islands.

Toxic lead

A previous study led by Green and colleagues found that pheasants killed by lead shot contained many fragments of lead too small to detect by eye or touch, and too distant from the shot to be removed without throwing away a large proportion of otherwise useable meat. This means that eating pheasant killed using lead shot is likely to expose consumers to raised levels of lead in their diet, even if the meat is carefully prepared to remove whole shotgun pellets and the most damaged tissue.

Lead has been banned from use in paint and petrol for decades. It is toxic to humans when absorbed by the body and there is no known safe level of exposure. Lead accumulates in the body over time and can cause long-term harm, including increased risk of cardiovascular disease and kidney disease in adults. Lead is known to lower IQ in young children and affect the neurological development of unborn babies.

The studies were part-funded by the RSPB, Waitrose & Partners, and an anonymous donor. They were supported by a group of unpaid volunteers, who are co-authors of the reports.
 

References

Green, R.E. et al: ‘The proportion of common pheasants shot using lead shotgun ammunition in Britain has barely changed despite five years of voluntary efforts to switch from lead to non-lead ammunition.’ March 2025, Conservation Evidence. DOI: 10.52201/CEJ22/EXYS6184

Green, R.E. et al.: ‘Sampling of red grouse carcasses in Britain indicates no progress during an intended five-year voluntary transition from lead to non-lead shotgun ammunition.’ February 2025, Conservation Evidence. DOI: 10.52201/CEJ22/YYWM1722
 

A voluntary pledge made by UK shooting organisations in 2020 to replace lead shot with non-toxic alternatives by 2025 has failed, analysis by Cambridge researchers finds.

The voluntary route has now been tested - with efforts made by many people - and it has not been successful.Rhys GreenAndy Hay, RSPBAdult pheasant

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YesLicence type: Attribution-Noncommerical

They say that discovering the mechanism will support ongoing clinical trials, and could lead to the targeted use of aspirin to prevent the spread of susceptible types of cancer, and to the development of more effective drugs to prevent cancer metastasis. 

The scientists caution that, in some people, aspirin can have serious side-effects and clinical trials are underway to determine how to use it safely and effectively to prevent cancer spread, so people should consult their doctor before starting to take it.

Studies of people with cancer have previously observed that those taking daily low-dose aspirin have a reduction in the spread of some cancers, such as breast, bowel, and prostate cancers, leading to ongoing clinical trials. However, until now it wasn’t known exactly how aspirin could prevent metastases.

Professor Rahul Roychoudhuri in the Department of Pathology at the University of Cambridge, who led the work, said: “Despite advances in cancer treatment, many patients with early stage cancers receive treatments, such as surgical removal of the tumour, which have the potential to be curative, but later relapse due to the eventual growth of micrometastases – cancer cells that have seeded other parts of the body but remain in a latent state. 

“Most immunotherapies are developed to treat patients with established metastatic cancer, but when cancer first spreads there’s a unique therapeutic window of opportunity when cancer cells are particularly vulnerable to immune attack. We hope that therapies that target this window of vulnerability will have tremendous scope in preventing recurrence in patients with early cancer at risk of recurrence.”

The study is published today in the journal 'Nature'.  

The scientists say their discovery of how aspirin reduces cancer metastasis was serendipitous. They were investigating the process of metastasis, because, while cancer starts out in one location, 90% of cancer deaths occur when cancer spreads to other parts of the body.

The scientists wanted to better understand how the immune system responds to metastasis, because when individual cancer cells break away from their originating tumour and spread to another part of the body they are particularly vulnerable to immune attack. The immune system can recognise and kill these lone cancer cells more effectively than cancer cells within larger originating tumours, which have often developed an environment that suppresses the immune system. 

The researchers previously screened 810 genes in mice and found 15 that had an effect on cancer metastasis. In particular, they found that mice lacking a gene which produces a protein called ARHGEF1 had less metastasis of various primary cancers to the lungs and liver. 

The researchers determined that ARHGEF1 suppresses a type of immune cell called a T cell, which can recognise and kill metastatic cancer cells. 

To develop treatments to take advantage of this discovery, they needed to find a way for drugs to target it. The scientists traced signals in the cell to determine that ARHGEF1 is switched on when T cells are exposed to a clotting factor called thromboxane A2 (TXA2).

This was an unexpected revelation for the scientists, because TXA2 is already well-known and linked to how aspirin works. 

TXA2 is produced by platelets - a cell in the blood stream that helps blood clot, preventing wounds from bleeding, but occasionally causing heart attacks and strokes. Aspirin reduces the production of TXA2, leading to the anti-clotting effects, which underlies its ability to prevent heart attacks and strokes. 

This new research found that aspirin prevents cancers from spreading by decreasing TXA2 and releasing T cells from suppression. They used a mouse model of melanoma to show that in mice given aspirin, the frequency of metastases was reduced compared to control mice, and this was dependent on releasing T cells from suppression by TXA2.

Dr Jie Yang in the Department of Pathology at the University of Cambridge, first author of the report, said: “It was a Eureka moment when we found TXA2 was the molecular signal that activates this suppressive effect on T cells. Before this, we had not been aware of the implication of our findings in understanding the anti-metastatic activity of aspirin. It was an entirely unexpected finding which sent us down quite a different path of enquiry than we had anticipated.” 

“Aspirin, or other drugs that could target this pathway, have the potential to be less expensive than antibody-based therapies, and therefore more accessible globally.”

In the future, the researchers plan to help the translation of their work into potential clinical practice by collaborating with Professor Ruth Langley, of the MRC Clinical Trials Unit at University College London, who is leading the Add-Aspirin clinical trial, to find out if aspirin can stop or delay early stage cancers from coming back. 

Professor Langley, who was not involved in this study, commented: “This is an important discovery. It will enable us to interpret the results of ongoing clinical trials and work out who is most likely to benefit from aspirin after a cancer diagnosis.” 

“In a small proportion of people, aspirin can cause serious side-effects, including bleeding or stomach ulcers. Therefore, it is important to understand which people with cancer are likely to benefit.”

The research was principally funded by the Medical Research Council, with additional funding from the Wellcome Trust and European Research Council. 

The Add-Aspirin clinical trial is funded by Cancer Research UK, the National Institute for Health and Care Research, the Medical Research Council and the Tata Memorial Foundation of India. 

Reference: J. Yang, et al: “Aspirin prevents metastasis by limiting platelet TXA2 suppression of T cell immunity.” Nature, March 2025. DOI: 10.1038/s41586-025-08626-7

Adapted from a press release by the Medical Research Council.

Scientists have uncovered the mechanism behind how aspirin could reduce the metastasis of some cancers by stimulating the immune system.

Aspirin has the potential to be less expensive than antibody-based therapies, and therefore more accessible globally.Jie YangTetra Images on Getty

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Duygu Sevilgen has built a coral lab in the basement of an old Zoology building. Here, 10 experimental tanks host multicoloured miniature forests, with each tank representing a different marine environment. Duygu uses extremely small sensors to record the fine details of coral skeletons and listen to their dialogue with algae. In doing so, she determines how much change corals can bear, and improves our chances of saving them in the wild.

More fires, taking hold over more months of the year, are causing more carbon to be released into the atmosphere as carbon dioxide.

Fires on peatlands, which are carbon-rich, can almost double global fire-driven carbon emissions. Researchers found that despite accounting for only a quarter of the total UK land area that burns each year, dwarfed by moor and heathland, wildfires that burn peat have caused up to 90% of annual UK fire-driven carbon emissions since 2001 – with emissions spikes in particularly dry years.

Peat only burns when it’s hot and dry enough - conditions that are occurring more often with climate change. The peatlands of Saddleworth Moor in the Peak District, and Flow Country in northern Scotland, have both been affected by huge wildfires in recent years.

Unlike heather moorland which takes up to twenty years to regrow after a fire, burnt peat can take centuries to reaccumulate. The loss of this valuable carbon store makes the increasing wildfire frequency on peatlands a real cause for concern. 

The researchers also calculated that carbon emissions from fires on UK peatland are likely to rise by at least 60% if the planet warms by 2oC. 

The findings, which are broadly relevant to peatlands in temperate climates, are published today in the journal 'Environmental Research Letters'.

“We found that peatland fires are responsible for a disproportionately large amount of the carbon emissions caused by UK wildfires, which we project will increase even more with climate change,” said Dr Adam Pellegrini in the University of Cambridge’s Department of Plant Sciences, senior author of the study.

He added: “Peatland reaccumulates lost carbon so slowly as it recovers after a wildfire that this process is limited for climate change mitigation. We need to focus on preventing that peat from burning in the first place, by re-wetting peatlands.”

"We found that in dry years, peatland wildfires were able to burn into the peat and release significant quantities of carbon into the atmosphere. In particularly dry years this contributed up to 90% of the total wildfire-driven carbon emissions from the UK," said Dr Sarah Baker, lead author of the study which she conducted while at the University of Cambridge. Baker is now based at the University of Exeter.

The researchers found that the UK’s ‘fire season’ - when fires occur on natural land - has lengthened dramatically since 2011, from between one and four months in the years 2011-2016 to between six and nine months in the years 2017-2021. The change is particularly marked in Scotland, where almost half of all UK fires occur.

Nine percent of the UK is covered by peatland, which in a healthy condition removes over three million tonnes of carbon dioxide from the atmosphere per year. 

The researchers estimate 800,000 tonnes of carbon were emitted from fires on UK peatlands between 2001 and 2021. The 2018 Saddleworth Moor fire emitted 24,000 tonnes of carbon, and the 2019 Flow Country fire emitted 96,000 tonnes of carbon from burning peat.

To get their results, the researchers mapped all UK wildfires over a period of 20 years – assessing where they burn, whether peat burned, how much carbon they emit, and how climate change is affecting fires. This involved combining data on fire locations, vegetation type and carbon content, soil moisture, and peat depth. Using UK Met Office model outputs, the team also used simulated climate conditions to project how wildfires in the UK could change in the future.

The study only considered land where wildfires have occurred in the past, and did not consider the future increases in burned area that are likely to occur with hotter, drier UK summers.

An average of 5,600 hectares of moor and heathland burns across the UK each year, compared to 2,500 hectares of peatland.

“Buffering the UK’s peatlands against really hot, dry summers is a great way to reduce carbon emissions as part of our goal to reach net zero. Humans are capable of incredible things when we’re incentivised to do them,” said Pellegrini.

The research was funded by Wellcome, the Isaac Newton Trust and UKRI.

Reference: Baker, S.J. et al: ‘Spikes in UK wildfire emissions driven by peatland fires in dry years.’ February 2025, Environmental Research Letters. DOI: 10.1088/1748-9326/adafc6.
 

A new study led by the University of Cambridge has revealed that as our springs and summers get hotter and drier, the UK wildfire season is being stretched and intensified.

Peatland fires are responsible for a disproportionately large amount of the carbon emissions caused by UK wildfires, which we project will increase even more with climate changeAdam PellegriniSarah BakerFire on UK moorland

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Some efforts to preserve or rewild natural habitats are shifting harmful land use to other parts of the world – and this could drive an even steeper decline in the planet’s species, according to a team of conservation scientists and economists led by the University of Cambridge.   

Researchers from over a dozen institutions worldwide have come together to call on the global community to acknowledge the “biodiversity leak”: the displacement of nature-damaging human activities caused by ringfencing certain areas for protection or restoration.

They argue that rewilding productive farmland or forestry in industrialised nations that have low levels of biodiversity may do more harm than good on a planetary scale.

Exploratory analysis by the team suggests that reclaiming typical UK cropland for nature may be five times more damaging for global biodiversity than the benefit it provides local species, due to the displacement of production to more biodiverse regions.   

While this “leakage” has been known about for decades, it is largely neglected in biodiversity conservation, say the researchers. They argue it undermines actions ranging from establishing new nature reserves to the EU’s environmental policies.

Writing in the journal Science, the experts point out that even the UN’s landmark Global Biodiversity Framework – aiming for 30% of the world’s land and seas to be conserved – makes no mention of the leakage problem.

“As nations in temperate regions such as Europe conserve more land, the resulting shortfalls in food and wood production will have to be made up somewhere,” said Prof Andrew Balmford, from the University of Cambridge’s Department of Zoology. 

“Much of this is likely to happen in more biodiverse but often less well-regulated parts of the world, such as Africa and South America. Areas of much greater importance for nature are likely to pay the price for conservation efforts in wealthy nations unless we work to fix this leak.”

“The first thing we need to do is collectively acknowledge that these leaks exist,” said co-author Prof Brendan Fisher from the University of Vermont. “If protesting a logging concession in the US increases demand for pulp from the tropics, then we are unlikely to be helping biodiversity.”

Co-author Dr Ben Balmford of the University of Exeter said: “This issue demands far greater attention from a sector that seeks to shape how 30% of an ever hungrier and more connected planet is managed.”

‘Leakage’ is already a major issue for carbon credits tied to forest preservation, say researchers. But they argue it’s a real problem for biodiversity conservation efforts too.

While protected areas can slow deforestation inside their borders, there’s evidence it can simply shift to neighbouring areas. Production can also be displaced much further. Efforts to protect the Pacific Northwest’s old-growth forests resulted in increased logging in other North American regions, for example.

Yet a survey of site managers of tropical conservation projects conducted by the Cambridge team found that 37% had not come across the concept of leakage, and less than half of the projects were attempting to curb any displacement damage.*

The researchers explored how leakage caused by protected areas could affect global biodiversity by applying real-world food and biodiversity data to two hypothetical conservation projects.

They found that rewilding a sizeable area of Brazilian soybean farms would push production to nations such as Argentina and USA, but because Brazil is so important for biodiversity, the local conservation gains could be around five times greater than the displacement harms.

The opposite would be true if the equivalent area of UK arable farmland was reclaimed for nature. Here, production would be displaced to Australia, Germany, Italy and Ukraine.**

As the UK has fewer species than these other countries, damage from ‘leakage’ could be five times greater than the local benefit to British biodiversity. 

The experts offer a number of ways to help plug the biodiversity leak. They call on governments and the conservation sector to take leakage far more seriously when making environmental policy at national and global level.

They also point out that leakage could be reduced if conservation projects work with others to reduce demand – especially for high-footprint commodities such as red meat.

There’s scope to limit leakage by targeting conservation to areas high in biodiversity but where current or potential production of food or timber is limited, say researchers. One example is restoring abandoned tropical shrimp farms to mangroves.

However, we should also be much more cautious about restoring natural habitats on currently productive farmland in less biodiverse parts of the world, they argue.

Beyond planning where to conserve, major conservation initiatives should work with partners in other sectors to support local farmers, so that overall levels of production are maintained in the region despite protected areas. The team cite examples ranging from forest-friendly chocolate to herding practices that protect snow leopards.

Where local yield increases are difficult, larger-scale programmes could establish long-range partnerships with suppliers in the same markets to make up shortfalls in production.

“Without attention and action, there is a real risk that the biodiversity leak will undermine hard-won conservation victories,” said co-author Dr Fiona Sanderson of the Royal Society for Protection of Birds, who works on reducing the impacts of cocoa production in Sierra Leone.

Lead author from Cambridge, Prof Andrew Balmford, added: “At its worst, we could see some conservation actions cause net global harm by displacing production to regions which are much more significant for biodiversity.” 

*Survey of 100 practitioners involved in area-based tropical conservation projects, including directors, managers, coordinators, and researchers. Respondents came from 36 countries across all five continents. Further details: https://zenodo.org/records/14780198

** Two hypothetical habitat restoration programs covering 1000km2 of Brazilian soy-producing land, and restoring 1000km2 of arable farmland in the UK that produces wheat, barley and oilseed rape.

Researchers call on the international community to recognise and start tackling the “biodiversity leak”. 

Areas of much greater importance for nature are likely to pay the price for conservation efforts in wealthy nations unless we work to fix this leakAndrew BalmfordMichael Duff, © RSPB-images.comThe Gola Rainforest Project in Sierra Leone. This conservation project has limited leakage while slowing deforestation by supporting nearby farmers such as Mallo Samah to increase their yields and get higher prices for their cocoa.

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Yes

The Cambridge Awards for Research Impact and Engagement, formerly the Vice-Chancellor's Award, are held annually to recognise exceptional achievement, innovation, and creativity in developing research engagement and impact plans with significant economic, social, and cultural potential. Awarded in three categories, the winners for 2024 are:

Established Academic

Winner: Professor Sander van der Linden (Department of Psychology, School of Biological Sciences and Churchill College) and his team at the Cambridge Social Decision-Making Lab (Team application)

Project: A Psychological Vaccine Against Misinformation

Professor Sander van der Linden and team have developed a novel approach to countering the spread of harmful misinformation. This ‘psychological vaccine’ resulted in award winning public impact tools that have shown millions of people how to spot fake news online. These games have been adopted by the World Health Organisation, United Nations, UK Government and Google and led to key policy changes in the EU Digital Services Act.

Early Career Researcher

Winner: Dr Gabriel Okello (Cambridge Institute for Sustainability Leadership, School of Technology)

Project: Applying multidisciplinary, collaborative approaches to tackle air pollution in rapidly urbanising African cities

The project catalysed Uganda’s first-ever Air Quality Standards, advancing policy and public health. It drove transformative growth in the e-mobility sector and battery-swapping stations. The Clean Air Network was established as a multi-regional community of practice for air quality management across Africa. The platform now provides real-time air quality data enabling evidence-based decision-making in Uganda and eight other African countries.

Collolaboration Award

Winner: 

Lead: Prof Paul Fletcher (Department of Psychiatry, School of Clinical Medicine, Clare College), Dr Dervila Glynn (Cambridge Neuroscience IRC), Dominic Matthews (Ninja Theory Ltd), Sharon Gilfoyle (Cambridgeshire and Peterborough NHS Foundation Trust)

Project: Representing psychosis in video games: Communicating clinical science and tackling stigma

This work draws together expertise in video game design and clinical neuroscience, with lived experience of mental illness to co-produce two award-winning video games vividly conveying the nature of altered experience of reality in a character with psychosis. Within conversations around mental health, psychosis is neglected and highly stigmatised.

In creating a powerful character and telling her story through gameplay, the project has enabled sensitive and thoughtful conversations about psychosis, and mental illness in general. It has had a measurably positive impact on stigma.

Find out more about the winning projects and meet our runners-up here: www.cam.ac.uk/public-engagement/cambridge-awards-2024. 

From helping to inoculate the public against misinformation to tackling air pollution in rapidly urbanising African cities, researchers from across the University of Cambridge were honoured at the Cambridge Awards yesterday (Monday 3rd February) afternoon.

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Yes

A major study of botanic gardens around the world has revealed their struggles with one fundamental aim: to safeguard the world’s most threatened plants from extinction.

Researchers analysed a century’s worth of records - from 1921 to 2021 - from fifty botanic gardens and arboreta currently growing half a million plants, to see how the world’s living plant collections have changed over time. 

The results suggest that the world’s living collections have collectively reached peak capacity, and that restrictions on wild plant collecting around the world are hampering efforts to gather plant diversity on the scale needed to study and protect it.

There is little evidence that institutions are managing to conserve threatened plants within collections, on a global scale, despite accelerating rates of elevated extinction risk.

The findings imply that tackling the loss of biodiversity has not been prioritised across the world’s botanic gardens as a collective - a fact the researchers say must be urgently addressed.

Curator of Cambridge University Botanic Garden Professor Samuel Brockington, who led the work, said: “A concerted, collaborative effort across the world’s botanic gardens is now needed to conserve a genetically diverse range of plants, and to make them available for research and future reintroduction into the wild.”

In their report, published in the journal Nature Ecology and Evolution, the researchers say the Convention on Biological Diversity (CBD) has effectively halved the level at which plants are being collected from the wild, and also created obstacles to the international exchange of plants.

Brockington, who is also Professor of Evolution in the University of Cambridge’s Department of Plant Sciences, said: “The impact of the Convention on Biological Diversity is a remarkable demonstration of the power and value of international agreements. But it seems to be preventing individual botanic gardens from working with many globally threatened plant species that we could help save from extinction.”

Collective thinking

As much as 40% of the world’s plant diversity is at elevated risk of extinction. Acceptance that individual collections have limited capacity to single-handedly prevent species extinction demands a rethink as to how they collaborate to store and safeguard diversity in living collections.

The researchers say it will be vital for the living collections to be considered as a ‘meta-collection’ in future: only by working closely together will the world’s botanic gardens be able to hold the range of plants needed to make a meaningful contribution to conservation efforts. This will include sharing data and expertise and supporting the development of new collections in the global south, where much of the world’s biodiversity is located. 

The researchers point out that some individual institutions, like the Royal Botanic Gardens Edinburgh, have successfully targeted and measurably conserved threatened conifer species. Similarly, Botanic Gardens Conservation International (BGCI) has established numerous global conservation consortia. However, these initiatives are the exception.

Wild decline

Plants must be regularly replaced or propagated within living collections: the average lifetime of a specimen is just 15 years. But the team’s analysis found that the number of wild-origin plants - those collected in the wild - in the collections peaked in 1993 and has been in decline ever since. 

“It is certainly not getting any easier to sustain the diversity of our collections. This is especially true for wild-collected plants, and they’re the most valuable for us in terms for supporting research, and in finding solutions to the twin challenges of climate change and global biodiversity loss,” said Brockington.

Weather worries

As climate change alters growing conditions in different regions of the world, it will become more challenging for individual botanic gardens to continue to grow such a diverse range of species.

Brockington said: “Climate change affects our work directly by altering local weather conditions - we’ve already seen record-breaking temperatures in Cambridge in recent years. That’s going to affect how well our plants survive, so we need to think rationally and collectively about the best locations to hold different species across the global network of living collections.” 

On 25 July 2019, Cambridge University Botanic Garden reached 38.70C - the highest temperature ever recorded in the UK at that time.

Diversity is key

Genetic diversity is important when it comes to protecting plants at risk of extinction, because it allows for breeding populations of species that can adapt to future challenges.

The more individual plants of a particular species in a collection, the greater the genetic diversity is likely to be. 

The team says data from the International Conifer Conservation Programme, run by the Royal Botanic Garden Edinburgh, shows that living collections can make a valuable contribution to conservation efforts - given the right resource and focus. By distributing threatened species across a network of safe sites, the trees are grown where they grow best, and as a whole they represent a strong sample of the genetic diversity of this important group.
Ethical collecting

Last year, Cambridge University Botanic Garden advertised for a new ‘Expedition Botanist’ to lead global plant-collection expeditions and contribute to vital conservation efforts. 

Brockington says these expeditions remain vital to work to safeguard and study the world’s plant species. He suggests that collaborative collecting work is possible, in a fair and ethical way, that builds equitable international partnerships. 

The CBD is a global agreement, signed by 150 government leaders in 1992, dedicated to promoting sustainable development. It makes each country responsible for protecting its own biodiversity, and supports fair and equitable sharing of the benefits arising out of the use of that biodiversity.

There are 3,500 botanic gardens and arboreta worldwide. They exist so that scientists can study, conserve and provide access to the world’s plants, as well as showcasing them to the public.

Botanic Gardens Conservation International (BGCI) is a charity whose purpose is to mobilise botanic gardens and engage partners in securing plant diversity for the wellbeing of people and the planet.

Reference: Cano, A. et al: ‘Insights from a century of data reveal global trends in ex situ living plant collections.’ Nature Ecology and Evolution, January 2024. DOI: 10.1038/s41559-024-02633-z
 

The world’s botanic gardens must pull together to protect global plant biodiversity in the face of the extinction crisis, amid restrictions on wild-collecting, say researchers.

A concerted, collaborative effort across the world’s botanic gardens is now needed to conserve a genetically diverse range of plants.Samuel BrockingtonHoward RiceCambridge University Botanic Garden

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The group of bacteria called Enterobacteriaceae, including Klebsiella pneumoniae, Shigella, E.coli and others, is present at low levels as part of a healthy human gut microbiome. But at high levels - caused for example by increased inflammation in the body, or by eating contaminated food - these bugs can cause illness and disease. In extreme cases, too much Enterobacteriaceae in the gut can be life-threatening.

Researchers have used computational approaches including AI to analyse the gut microbiome composition of over 12,000 people across 45 countries from their stool samples. They found that a person’s microbiome ‘signature’ can predict whether a person’s gut is likely to be colonised by Enterobacteriaceae. The results are consistent across different states of health and geographic locations.

The researchers identified 135 gut microbe species that are commonly found in the absence of Enterobacteriaceae, likely protecting against infection.

Notable amongst the protective gut species are a group of bacteria called Faecalibacterium, which produce beneficial compounds called short-chain fatty acids by breaking down fibre in the foods we eat. This seems to protect against infection by a range of disease-causing Enterobacteriaceae bugs.

The researchers suggest that eating more fibre in our diet will support the growth of good bacteria - and crowd out the bad ones to significantly reduce the risk of illness.

In contrast, taking probiotics - which don’t directly change the environment in the gut - is less likely to affect the likelihood of Enterobacteriaceae infection.

The results are published today in the journal Nature Microbiology. 

“Our results suggest that what we eat is potentially very important in controlling the likelihood of infection with a range of bacteria, including E.coli and Klebsiella pneumoniae, because this changes our gut environment to make it more hostile to invaders,” said Dr Alexandre Almeida, a researcher at the University of Cambridge’s Department of Veterinary Medicine and senior author of the paper.

He added: “By eating fibre in foods like vegetables, beans and whole grains, we can provide the raw material for our gut bacteria to produce short chain fatty acids - compounds that can protect us from these pathogenic bugs.”

Klebsiella pneumonia can cause pneumonia, meningitis and other infections. The alarming global rise in antibiotic resistance to this bacterial pathogen has led scientists to look for new ways of keeping it, and other similar infectious bacteria, under control. 

“With higher rates of antibiotic resistance there are fewer treatment options available to us. The best approach now is to prevent infections occurring in the first place, and we can do this by reducing the opportunities for these disease-causing bacteria to thrive in our gut,” said Almeida.

A new understanding of gut microbe interactions

Earlier research to understand interactions between the different bacteria in our gut has used mouse models. But some of these new results are at odds with previous findings. 

The new study revealed that 172 species of gut microbe can coexist with disease-causing Enterobacteriaceae bugs. Many of these species are functionally similar to the bugs: they need the same nutrients to survive. Previously it was thought that competition for resources would stop the disease-causing bacteria from getting established in the gut.

This has important implications for treatment: taking probiotics that compete for the same nutrients with the bad bacteria to try and starve them out isn’t going to work. The researchers say that it will be more beneficial to change the environment in the gut, for instance through diet, to reduce the risk of infection with Enterobacteriaceae.

“This study highlights the importance of studying pathogens not as isolated entities, but in the context of their surrounding gut microbiome,” said Dr Qi Yin, a visiting researcher at the University of Cambridge’s Department of Veterinary Medicine and first author of the report.

The research was funded by the Medical Research Council.

Reference: Yin, Q. et al: 'Ecological dynamics of Enterobacteriaceae in the human gut microbiome across global populations.’ Jan 2025, Nature Microbiology. DOI: 10.1038/s41564-024-01912-6.

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A new study has found that the composition of your gut microbiome helps predict how likely you are to succumb to potentially life-threatening infection with Klebsiella pneumoniae, E.coli and other bugs - and it may be altered by changing your diet.

Our results suggest that what we eat is potentially very important in controlling the likelihood of infection with a range of bacteria.Alexandre AlmeidaCredit Oleksandra Troian GettyIntestine with microbiome

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