SPIA – Stick insects as Parthenogenetic Indicators of Air pollution is a PRIN 2022 project coordinated by Leonardo Vignoli at the Department of Science, Roma Tre University.
The project explores the use of parthenogenetic stick insects as sentinel organisms for air pollution. Clonal reproduction makes it possible to work with genetically very similar individuals, reducing one source of variation and making biological responses to environmental exposure easier to interpret.
The model species is the Mediterranean stick insect Bacillus rossius, which can reproduce through apomictic parthenogenesis and generate genetically identical individuals. The animals are entirely captive-bred in controlled colonies, ensuring a constant supply of individuals without affecting wild populations.
This approach addresses one of the main limitations of traditional biomonitoring: individual genetic variability, which can make it difficult to distinguish pollutant effects from normal differences among organisms. Using clonal individuals reduces this background noise and produces responses that are more comparable, replicable and sensitive, including under chronic or low-dose exposure.
Clonal colonies maintained under controlled conditions are used to compare the responses of stick insects exposed to different levels and types of contamination. The analyses combine phenotypic and behavioural observations with molecular markers measured through qPCR assays.
The expected outcome is a portable, predictive and highly sensitive biomonitoring tool capable of assessing biological damage caused by terrestrial and atmospheric pollution. Standardising the responses of clonal organisms could make the method replicable across different contexts and support the development of innovative ecotoxicology protocols.
The project is funded under PRIN 2022 and NextGenerationEU.