Researchers from the Hessian State Museum Darmstadt and the Senckenberg Biodiversity and Climate Research Center Frankfurt have uncovered the factors that determine the enormous diversity of herbivorous insects. In their study, published today in the scientific journal “PNAS,” they show that the diversity of herbivorous insects evolved over the last 60 million years primarily through the shared use of food plants. The results are based on the analysis of feeding traces left by arthropods on more than 45,000 fossil leaves.

Herbivorous insects are the most diverse group of multicellular organisms on Earth. The variety of their mouthparts and feeding modes also testify to a high degree of diversity: for example, there are caterpillars or beetles that chew on leaves with their powerful jaw-like mouthparts, bugs and aphids that pierce plants to get at their sap, or animals that stimulate plants to form galls – an excessive tissue growth – in which they can develop and feed protected from enemies. “The feeding traces of such insects are also clearly visible on fossil leaves. They can help us to identify the factors that led to the enormous diversity of herbivorous insects,” explains Dr. Jörg Albrecht from the Senckenberg Biodiversity and Climate Research Center in Frankfurt.