Researchers are exploring how the intricate and collaborative behavior of honey bees (Apis mellifera) is genetically encoded, allowing it to be inherited by future generations. Their investigation centers around a gene known as the doublesex gene (dsx).
A team from Heinrich Heine University Düsseldorf (HHU), alongside researchers from institutions in Frankfurt/Main, Oxford, and Würzburg, is examining the genetic basis of the complex social behaviors exhibited by honey bees (Apis mellifera) and how these behaviors can be transmitted to later generations. Their findings, published in the journal Science Advances, point to the involvement of a gene called doublesex (dsx).
The ways in which organisms interact are essential and often passed down through generations. Every person and animal engages with others in their social circles through various behaviors. In the animal world, social interaction plays a crucial role in activities such as group foraging, protecting against predators, and raising young ones.
In species like honey bees, social bonds are developed to such an extent that the colony members collectively operate as a single “superorganism.” Thousands of worker bees demonstrate their behavior by safeguarding the hive, providing food, and nurturing the larvae.
Professor Dr. Martin Beye, head of the Institute of Evolutionary Genetics at HHU and the leading author of the recent study in Science Advances, underscores that “the array of behaviors that bees exhibit and their roles within the colony are inherited rather than learned. The genetic basis of such complex behaviors was previously unknown.”
In collaboration with researchers from universities in Frankfurt/Main, Oxford, and Würzburg, Beye’s team, including primary author Dr. Vivien Sommer, has identified that a specific gene known as dsx defines the behaviors particular to worker bees.
Dr. Sommer explains: “This gene determines whether a worker bee performs a task in the colony and the duration of that task. This encompasses cooperative tasks like caring for the larvae, foraging for nectar, and engaging in social interactions regarding food sources.”
To carry out their research, the biologists employed CRISPR/Cas9 technology to modify or deactivate the dsx gene in specific bees. Each genetically altered bee was assigned a QR code and their behavior was monitored within the hive using camera systems. The video footage was analyzed through artificial intelligence to discern their individual behavioral patterns.
Sommer states, “Our main inquiry was whether and how the inherited behaviors would shift as a result of modifying the gene. Such alterations should manifest in the nervous system of the worker bees, where these particular behaviors are regulated.”
The researchers incorporated a green fluorescent protein (GFP) into the dsx gene sequence, leading to the simultaneous production of GFP and the dsx protein. This modification allowed them to visualize neuronal connections in both genetically unaltered and altered bees using fluorescence microscopy. “These methods enabled us to identify the precise neural pathways that the dsx gene establishes in the brain and how it influences the inherited behaviors of honey bees,” notes doctoral researcher Jana Seiler, a co-author of the study.
“Our results suggest a key genetic program that shapes the neural circuitry and behavior of worker bees,” adds Professor Dr. Wolfgang Rössler from the Department of Behavioural Physiology and Sociobiology, who oversaw the Würzburg part of the study.
The next phase for the researchers is to transition their focus from individual honey bees to the concept of the bee colony as a superorganism. Dr. Alina Sturm, another doctoral researcher and co-author, emphasizes, “We aim to uncover the connection between individual genetic programming and the coordinated actions of the group.”
