Insect behavior under the microscope: Study reveals reproducibility problems!

Insect behavior under the microscope: Study reveals reproducibility problems!

A current report from the University of Münster highlights the challenges of reproducibility in insect behavioral biology. An interdisciplinary research team from the universities of Münster, Bielefeld and Jena carried out behavioral studies with the common grasshopper (Pseudochorthippus parallelus), which is considered a common model organism in evolutionary biology. The reproducibility crisis, which is increasingly being discussed in the scientific community, also affects the results of this insect research.

The study shows that under controlled conditions in behavioral experiments with insects, consistent results were only achieved in about half of the experiments. Depending on the definition, deviations in reproducibility were between 17 and 42 percent. While reproducibility has been widely studied in biomedical research, there is currently a lack of systematic studies focusing on insect behavior. This is particularly striking because insect research often uses large sample sizes, which would suggest more robust results.

Details of the experiments

Under the direction of Prof. Dr. Helene Richter, the scientists in Münster, Bielefeld and Jena carried out three different behavioral experiments, each aimed at specific insect species:

• Die Auswirkungen von Futtermangel auf die Abwehrreaktionen bei Larven der Rübsen-Blattwespe (Athalia rosae).
• Der Zusammenhang zwischen Körperfarbe und bevorzugter Umgebungsfarbe bei Grashüpfern.
• Die Habitatwahl bei Red Flour Beetle (Tribolium castaneum).

The results of the experiments were systematically compared and illustrate the difficulties in reproducing behavioral studies in different laboratories.

Revealing numbers

Another study from the Biological Preprint Database revealed that statistical treatment effects could be successfully reproduced in 83% of experiment replicates. However, the reproducibility of the effect size was only present in 66% of cases. This discrepancy highlights the complexity of the experimental conditions. Furthermore, it was found that the problems of reproducibility that are present in research on mammals such as rats are also relevant for studies on insects.

The researchers advocate a rethink in the scientific community. They recommend open research practices and the implementation of methodological strategies to reduce bias and avoid problems caused by over-standardization. In particular, the introduction of systematic variations could make a significant contribution to improving reproducibility in studies of living organisms.

The study, which is considered the first systematic investigation of the reproducibility of insect behavior studies, was financially supported by the German Research Foundation (DFG) as part of the Transregio Collaborative Research Center “Niche Choice, Niche Conformity, Niche Construction” (NC3). The original publication is in PLOS Biology to find.