Working with Royal Botanic Gardens Kew, the University of Greenwich, and the Technical University of Denmark, the scientists engineered a diet that mimics the key nutrients bees normally get from pollen.

When tested, colonies fed this supplement produced up to 15 times more young. The findings were published in the journal Nature.

Bees Are Starving for the Right Nutrients

Honeybees rely on pollen as their main food source. It contains essential lipids called sterols that are critical for growth and development.

But climate change and intensive farming have reduced the variety of flowers bees depend on. As a result, bees are increasingly missing key nutrients.

Beekeepers often use artificial pollen substitutes made from protein flour, sugars, and oils. These provide calories but lack the sterols bees need, leaving colonies nutritionally deficient.

A Lab-Made Solution Using Engineered Yeast

To fill this gap, researchers engineered the yeast Yarrowia lipolytica to produce a precise mix of six essential sterols.

They added this yeast to bee diets and tested it over three months in controlled glasshouse experiments. The enclosed setup ensured bees ate only the experimental feed.

Colonies Grew Faster and Stayed Healthier

The results were dramatic. Colonies receiving the enriched diet produced up to 15 times more larvae that reached the pupal stage compared with those on standard diets.

They also continued raising brood throughout the entire study period. Colonies without sterols stopped producing brood after about 90 days.

Even more striking, the nutrient profile of larvae matched that of bees feeding naturally, suggesting the supplement closely replicates real pollen nutrition.

Scientists Say This Could Be a Game Changer

Senior author Professor Geraldine Wright (Department of Biology, University of Oxford), said: “Our study demonstrates how we can harness synthetic biology to solve real-world ecological challenges. Most of the pollen sterols used by bees are not available naturally in quantities that could be harvested on a commercial scale, making it otherwise impossible to create a nutritionally complete feed that is a substitute for pollen.”

Lead author Dr. Elynor Moore (Department of Biology, University of Oxford at the time of the study, now Delft University of Technology) added: “For bees, the difference between the sterol-enriched diet and conventional bee feeds would be comparable to the difference for humans between eating balanced, nutritionally complete meals and eating meals missing essential nutrients like essential fatty acids. Using precision fermentation, we are now able to provide bees with a tailor-made feed that is nutritionally complete at the molecular level.”

Cracking the Code of Bee Nutrition

To figure out what bees actually need, researchers analyzed tissues from pupae and adult bees. This required extremely delicate lab work, including dissecting individual nurse bees.

They identified six key sterols that dominate bee biology: 24-methylenecholesterol, campesterol, isofucosterol, β-sitosterol, cholesterol, and desmosterol.

CRISPR and Yeast Make It Scalable

Using CRISPR-Cas9 gene editing, the team programmed Yarrowia lipolytica to produce these sterols efficiently.

This yeast was chosen because it naturally produces lipids, is safe for food use, and can be scaled up for industrial production. The final supplement is made by growing the yeast in bioreactors and drying it into a powder.

Why This Matters for Food and Farming

Honeybees help produce more than 70% of major global crops. But their populations are under severe pressure from poor nutrition, climate change, parasites, disease, and pesticides.

In the U.S., annual colony losses have ranged from 40 to 50% in recent years and could reach as high as 60 to 70% in 2025.

This new supplement could strengthen bee health without increasing competition for limited wildflowers. It may even evolve into a complete nutritional feed.

Helping Wild Bees Too

Co-author Professor Phil Stevenson (RBG Kew and Natural Resources Institute, University of Greenwich) added: “Honey bees are critically important pollinators for the production of crops such as almonds, apples, and cherries and so are present in some crop locations in very large numbers, which can put pressure on limited wildflowers. Our engineered supplement could therefore benefit wild bee species by reducing competition for limited pollen supplies.”

A Potential Breakthrough for Beekeepers

Danielle Downey (Executive Director of honeybee research nonprofit Project Apis m., not affiliated with the study) said: “We rely on honey bees to pollinate one in three bites of our food, yet bees face many stressors. Good nutrition is one way to improve their resilience to these threats, and in landscapes with dwindling natural forage for bees, a more complete diet supplement could be a game changer. This breakthrough discovery of key phytonutrients that, when included in feed supplements, allow sustained honey bee brood rearing has immense potential to improve outcomes for colony survival, and in turn the beekeeping businesses we rely on for our food production.”

What Happens Next

Larger field trials are still needed to confirm long-term benefits. If successful, the supplement could reach farmers within two years.

The same technology could also be adapted to support other pollinators or farmed insects, opening new paths for sustainable agriculture.

That assumption is now being questioned thanks to a real cow named Veronika. A study published in Current Biology reports the first documented case of tool use in a pet cow, suggesting that cattle may be far more cognitively capable than previously believed.

“The findings highlight how assumptions about livestock intelligence may reflect gaps in observation rather than genuine cognitive limits,” says Alice Auersperg, a cognitive biologist at the University of Veterinary Medicine, Vienna.

Meet Veronika, the Tool-Using Cow

Veronika is a Swiss Brown cow who lives as a companion animal rather than being raised for food production. She belongs to Witgar Wiegele, an organic farmer and baker who considers her part of the family.

More than a decade ago, Wiegele noticed an unusual behavior. Veronika would pick up sticks and use them to scratch her body. This behavior eventually caught scientific attention when it was recorded on video and shared with researchers.

“When I saw the footage, it was immediately clear that this was not accidental,” Auersperg says. “This was a meaningful example of tool use in a species that is rarely considered from a cognitive perspective.”

Testing Tool Use in Controlled Experiments

To better understand this behavior, researchers conducted structured tests with Veronika. They placed a deck brush on the ground in different positions and observed how she interacted with it.

Across multiple trials, Veronika consistently chose specific parts of the brush depending on where she wanted to scratch. Her selections were not random. Instead, they matched the needs of different areas of her body.

“We show that a cow can engage in genuinely flexible tool use,” says Antonio Osuna-Mascaró. “Veronika is not just using an object to scratch herself. She uses different parts of the same tool for different purposes, and she applies different techniques depending on the function of the tool and the body region.”

Flexible and Multi-Purpose Tool Use

The researchers found clear patterns in how Veronika used the brush. For larger, firmer areas like her back, she preferred the bristled side. For more sensitive regions on her lower body, she switched to the smoother handle.

She also adjusted her movements. Scratching her upper body involved broader, stronger motions, while movements directed at lower areas were slower and more precise.

Tool use is defined as using an external object to achieve a goal through physical interaction. Veronika’s actions meet this definition and go beyond it. Her behavior qualifies as flexible, multi-purpose tool use, meaning she uses different features of the same object for different outcomes.

This type of behavior is extremely rare and has previously been clearly documented only in chimpanzees among non-human species.

Overcoming Physical Limitations

Veronika’s tool use is directed at her own body, which is known as egocentric tool use. While this form is typically considered less complex than using tools on external objects, it still presents challenges.

Because cows lack hands, Veronika must manipulate tools using her mouth. Despite this limitation, she shows careful control and appears to anticipate the effects of her actions. She adjusts her grip and movements to achieve the desired result.

Why This Behavior May Be Rare

The researchers believe Veronika’s unique living conditions may have contributed to her behavior. Unlike most cattle, she has lived a long life in a complex and stimulating environment. She has daily interactions with humans and access to a variety of objects she can manipulate.

These factors likely created opportunities for exploration and innovation that are uncommon for most cows.

“[Veronika] did not fashion tools like the cow in Gary Larson’s cartoon, but she selected, adjusted, and used one with notable dexterity and flexibility,” the researchers write. “Perhaps the real absurdity lies not in imagining a tool-using cow, but in assuming such a thing could never exist.”

Rethinking Animal Intelligence

This discovery represents the first confirmed case of tool use in cattle and expands the range of species known to demonstrate this ability. It also raises the possibility that similar behaviors may exist but have gone unnoticed.

The research team is now exploring which environmental and social conditions allow such behaviors to develop. They also encourage others to report similar observations.

“Because we suspect this ability may be more widespread than currently documented,” Osuna-Mascaró says, “we invite readers who have observed cows or bulls using sticks or other handheld objects for purposeful actions to contact us.”