As the world drowns in plastic, researchers are searching for practical materials that are lightweight, strong, and biodegradable. In recent years, scientists have increasingly turned to the natural world for inspiration, and a significant portion of research has focused on the impressive properties of spider silk.
But there is another promising alternative that often goes unnoticed: bee silk. If you’re feeling puzzled right now, you’re not alone. Most people have never heard of bee silk.
“The production of silk in nature is far more common than most people realize,” said Oan Wasserman from Utah State University. “Silk has evolved independently many times, and among insects alone, including ants, bees, and wasps, there are at least 23 separate evolutionary origins.”
Earlier this year, Wasserman and his team became the first to create a film showcasing a specific type of bee silk—an important first step in harnessing the potential of this incredible material. The findings were published in the journals PLOS One and SynBio.
In the insect world, silk can be used for everything from weaving webs and building nests to spinning cocoons. For bees, in particular, its purpose is protection.
“Social bees, like honeybees and bumblebees, produce silk to line the brood cells in their colonies,” Wasserman said. “Solitary bees, which make up about 75 percent of all bee species, spin silk to create cocoons that shield them from adverse environmental conditions.”
That’s right—about three-quarters of all bee species spin silk.
Researchers have been studying the properties of various types of bee silk for around 20 years, but Wasserman and the Jones lab have gone a step further by developing a non-invasive method for synthesizing silk.
This is important because, while everyone knows how impressive spider silk is—five times stronger than steel by weight!—it is incredibly difficult to replicate in a laboratory setting.
In his research, Wasserman focused on the blue orchard bee (Osmia lignaria), a solitary bee and a key pollinator in gardens, which has small, brownish, elongated cocoons with a distinctive nipple-like cap at one end. These cocoons are much tougher than they appear.
Although both silkworms and blue orchard bees use silk to build cocoons, they produce silk in completely different ways. A silkworm spins its cocoon from a single continuous thread.
As Wasserman explained, a bee larva takes a more architectural approach. It attaches a strand to the wall of the nest cell, drags the thread using head movements, and secures it at a new spot, repeating the process until the chamber is fully enclosed.
The resulting cocoon has only a few structural layers, but they work together to provide a balance of gas exchange, mechanical protection, moisture retention, and resistance to parasites. The last point is more significant than it might seem.
Solitary bee cocoons face a very real threat: parasitic wasps. These are wasps that detect bee cocoons using chemical signals and then attempt to pierce them with a needle-like structure to lay eggs inside the developing bee (yuck, we know). The bee’s silk cocoon is essentially the larva’s only line of defense.
In addition to its incredible puncture resistance (a property the Jones lab is actively studying), this material is also flexible, antimicrobial, and breathable.
That’s exactly the combination you would need for next-generation biomedical materials, such as surgical sutures, tissue engineering scaffolds, and technical textiles. However, the challenge in leveraging these properties has been recreating the silk outside the bee larva.
Wasserman’s early attempts involved extracting individual silk fibers from finished cocoons, but this process was labor-intensive and resulted in frequent breakages. So the team went back to the drawing board.
“The protocol we developed allows us to isolate silk fibers directly from the larva’s mouth opening,” Wasserman explained.
To do this, they use a 3D-printed bee-rearing system that mimics the natural nest of a bee house, and then raise the larvae inside it. The team monitors each larva daily and intervenes at the very moment it begins to spin—when the first threads are still loose and within reach. The fibers are then isolated and fixed for mechanical testing.
“One of the most promising aspects of the protocol is that the larvae continue to form their cocoons, indicating that the method is minimally invasive,” Wasserman said.
By isolating these fibers, the team was able to produce silk from scratch, using molecular biology techniques to insert target genes into a genetically modified microorganism that produced them in the lab. They then purified the resulting proteins (called fibroins) and cast them into transparent, self-supporting films.
This is the first time a bee silk protein produced in this way from a single bee has been turned into a material. Although this method is not yet directly applicable to any specific uses, it opens the door to further study of bee silk across different bee species.
For example, honeybee silk is known to be more elastic than orchard bee silk, and this same method could potentially be used to recreate that silk or even blend it with other materials.
That’s exactly what Wasserman and his team are now doing, using bee silk in combination with something even stranger: hagfish slime.
Hagfish are ancient, jawless deep-sea fish that release a viscous substance when threatened. This substance quickly swells in seawater, clogging the gills of attacking predators.
This slime is a mixture of mucus and thin protein threads, and when these threads are stretched and dried, their mechanical properties approach those of spider silk.
In Wasserman’s lab, the same molecular method is used for both hagfish proteins and bee silk, and both materials share a similar basic protein structure. This means they could potentially be blended to create materials that combine the best qualities of each.
“Silk has been used for various purposes for thousands of years. Yet, most attention has focused on only a few species, mainly silkworms and spiders,” Wasserman said. “Overall, insect silk is remarkably diverse, spun by many species with differences in composition and mechanical properties… But surprisingly, many aspects, such as silk and cocoons, remain poorly understood. As this field continues to develop, I expect many of these open questions will begin to find answers.”
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