These scientists are taking a fresh look at familiar organisms such as mussels, honey, and insects, which prove as unlikely but powerful tools to uncover hidden dimensions of our ecosystem. While one project explores how honey and mussels can serve as natural detectors of environmental health, the other delves into the genetic mysteries of the yellow mealworm, aiming to better understand how organisms adapt to environmental change. Though distinct in approach, both projects share a common goal: to sharpen our understanding of the natural world and bolster efforts to protect it.

Honey and Mussels: Nature’s Pollution Sleuths

When we hear the word "radioactivity", most of us think of nuclear accidents or industrial waste. But in fact, radioactivity is a natural part of life like a cosmic process that has existed since the dawn of time. Elements like potassium, carbon, uranium and thorium are naturally radioactive and can be found in the soil beneath our feet, the water we drink, the air we breathe  and even in our bones. Each second, roughly 5,000 atoms in the human body decay, emitting radiation that evolution has long taught us to live with.

Dr Katja Magdić Košiček is leading a project titled “Mussels and Honey as Bioindicators of Radioactivity in the Marine and Terrestrial Environment”, based on the Pelješac Peninsula. Here, bees and mussels are cast in the role of environmental inspectors, each in their own domain.

Bees, acting as land-based secret agents, visit hundreds of flowers daily, bringing back not just nectar but also microscopic particles from their environment, including radioactive isotopes. These particles become embedded in the honey they produce, turning this sweet substance into a natural archive of environmental radioactivity. Crucially, honey can reveal not only naturally occurring radionuclides such as polonium, but also artificial ones like radioactive caesium—clear indicators of human-induced contamination.

Mussels, on the other hand, are the perfect marine sentinels. These bivalves filter up to 80 litres of seawater each day in search of nutrients—retaining within their tissues any pollutants they encounter along the way, including heavy metals and radioactive substances. Their ability to accumulate such contaminants makes them ideal for monitoring the health of marine ecosystems.

“The health of our environment is directly tied to human health,” Dr Magdić Košiček explains. “This study provides a comprehensive picture of how radionuclides move through land and sea around Pelješac. The results will form a crucial baseline for monitoring radioactivity across Croatia—an issue of growing importance in the context of global events such as the war in Ukraine and rising concerns around potential contamination.”

Cracking the Genetic Code of an Insect with a Double Life

It’s not just bees and mussels doing the heavy lifting, an unassuming insect is also stepping into the spotlight. In a separate project led by Dr Eva Šatović Vukšić of the IRB’s Division of Molecular Biology, the yellow mealworm is offering a peek into the inner workings of genome.

“The yellow mealworm leads a double life,” says Dr Šatović Vukšić. “It’s both a nuisance—infesting food stores—and a rising star in animal feed production due to its high protein content. Since 2022, the EU has even approved it for human consumption, so we urgently need to know more about its biology.”

Thanks to its ease of breeding, short life cycle and high reproductive rate, the yellow mealworm is a popular model organism for scientific research. But what makes it even more intriguing is its genetic makeup.

Think of its genome as a vast library filled with well-known and widely read books—but also with mysterious, dust-covered volumes tucked away in the back. These are the satellite DNAs (satDNA), part of what scientists call the genome’s “dark matter.” Though they make up a large portion of the genome, we still know little about their function or significance.

Dr Šatović Vukšić’s project, “Shedding Light on the Roles of Genome ‘Dark Matter’ in the Function of the Economically Important Beetle Tenebrio molitor”, aims to map where these sequences lie within the genome, observe how they behave, and investigate how they influence the insect’s development and resilience, particularly under stress.

“Our research may uncover the hidden mechanisms that allow this insect to adapt so effectively to changing conditions,” Dr Šatović Vukšić explains. “Understanding these processes could also help us decode how genomes function and evolve. Beyond that, studying this insect enhances our knowledge of insect biology, their life cycles and survival strategies—providing insights of great value to agriculture, ecology, and the food industry.”

These two interesting projects exemplify how the smallest creatures, and even the food on our tables, can hold the key to answering some of today’s most pressing environmental and biological questions. By tuning in to nature’s subtle messages, scientists at the Ruđer Bošković Institute are helping us read between the lines and prepare for a more sustainable future.