We’ve recently found out that it gets even more interesting. Two species of Mediterranean beetles are capable of seeing red, throwing longstanding scientific assumptions about insect eyesight into disarray. The study was led by an international team of researchers. It features the unprecedented visual prowess of the beetles that call the eastern Mediterranean home. That pioneering work was recently published in the Journal of Experimental Biology. It provides new perspectives to inform our understanding of the ecology of these important pollinators.
The research team did include some big names. The Chair of Zoology II at the Biocentre of Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany, led by Dr. Johannes Spaethe, and the Würzburg Bioinformatics Chair, led by Dr. Elena Bencúrová, were instrumental. Coauthors from the University of Ljubljana in Slovenia and the University of Groningen in the Netherlands collaborated on this study. Their collaboration is an amazing example of international collective action.
Discovery of Red Color Perception
Additionally, no one knew that the retinas of these two beetle species contained four different types of photoreceptors. These four photoreceptors are excellent at absorbing ultraviolet light, blue light, green light, and deep red light. This finding represents an enormous step forward in our understanding of beetles’ visual potential. Until recently, the scientific consensus was that seeing red was exceptional among insects.
“To our knowledge, we are the first to have experimentally demonstrated that beetles can actually perceive the color red,” – Dr. Johannes Spaethe
This new capability enlivens some fascinating avenues for research. With the first genomic tools available, scientists can further investigate how these beetles interact with their environment, particularly in terms of their roles as pollinators. Their discovery indicates that these beetles have independently evolved visual systems to adapt, likely multiple times. It equips them to better understand the lively and complex flora of their home, Mediterranean basin.
Flower Color Preferences and Adaptation
This new research investigated the flower color preferences of two different beetle species. These species are within the genera Eulasia, Glaphyrus, and Pygopleurus. The researchers found that these beetles have a surprisingly wide spectrum of preferences for flower colors. They are particularly attracted to the colors red, violet, white, and yellow. This variety is especially important considering the amazing diversity of flower colors that originated from the Mediterranean basin.
Dr. Spaethe noted the implications of these findings for understanding ecological interactions: “The prevailing opinion in science is that flower colors have adapted to the visual systems of pollinators over the course of evolution.” In response, specific pollinators—such as beetles—adapted their vision to enhance foraging efficiency. It’s through this relationship that we get to experience the beautiful, dynamic interaction between plants and their pollinators.
A New Model for Visual Ecology Research
The Glaphyrid family of beetles is emerging as a promising new model system for investigating both visual ecology and the evolution of flower signals. The researchers are eager to continue researching these beetles. They hope this research will provide a better understanding of how pollinators are able to detect and respond to floral cues.
Now, scientists are trying to figure out just how special beetle vision is. They hope that further studies will help to characterize how various species acclimatize to their changing habitats and how these adaptations impact larger ecological interactions. The involvement of expertise from multiple international institutions is a testament to the team-oriented nature of today’s scientific inquiry.