Spy on the wood pigs to see if the soil is polluted

To think that an evolved and presumptuous species like ours can learn something from you earth pigs – those little armored creatures that we all played with as children, making them close up like a hedgehog – may seem unrealistic. Yet they were the ones, thanks to a project by the researchers from the University of Milan-Bicoccathey can help us understand if land is polluted and could in the future play a role, for example, in mapping of the quality of urban soils. How? Interpreting their behavior.

Earth pigs are crustaceans, the only ones to have colonized the mainland starting from the Lower Carboniferous, between 359.2 and 318.1 million years ago: by leaving the water they had to adapt by first compensating for dehydration. The evolutionary solution devised by the species was of a social nature: wood pigs tend to stay together, reducing the surface area in contact with the air. “They are crustaceans and need a lot of humidity. In normal conditions we find them all aggregated, literally one on top of the other,” he explains Sara Villa, professor of Ecology at the Milan-Bicocca University and member of the research team: “It is a survival strategy implemented to reduce the evotranspiration of water.” Things change under stress-induced conditions contaminated soil. “The group in this case fragments. The wood pigs are no longer capable of staying together: we think they are no longer able to communicate.” The idea of ​​the researchers at the University of Milan-Bicocca is to use this behavior as index of soil quality.

I changes in the sociality of piglets it’s theirs state of aggregation they will be monitored through a device composed of a plexiglass arena, an infrared micro-camera that detects and records movements and a artificial intelligence system who interprets them. “Our final goal is to develop a prototype that uses the automatic analysis procedure already patented by Elisabetta Fersini, professor of Computer Science at our university, to quantify the aggregation state of piglets when exposed to contaminated soil”, clarifies Villa. It’s about using the machine learning to automate the reading of the results of what ecotoxicologists call avoidance tests. A test that works roughly like this: soil is distributed inside a tray, contaminated land on one side, non-contaminated land on the other. If we put an earthworm or a wood pig in the tray, they will move (avoidance) from the polluted side to the “clean” one.

The innovation imagined by the Italian researchers is to move from an individual test to a team one, thus obtaining richer information: “Usually – specifies Villa – only one individual is observed, but by observing a group we move to a higher hierarchical level of ecological organization , much more informative than the response of an individual, which although very useful is still linked to individual characteristics”. To statistically quantify the degree of disaggregation, researchers from the University of Milan-Bicocca have developed a algorithm that from the movements of crustaceans in a few hours returns a synthetic index on the quality of the environment where they are placed: “It tells us whether the land is suitable to be populated or not”.

To develop an instrumental prototype that enhances and makes measurement more efficient, a project was launched crowdfunding campaign (“Many Little Pigs!”): first objective, 10,000 euros, achieved in a week, new objective, another 3,500, to investigate how the contaminants present in the soil prevent correct communication between these crustaceans (which to ‘talk’ to each other emitting pheromones). “Thanks to crowdfunding we will develop a better observation method for the gregarious behavior of wood pigs,” he says Lorenzo Federicoproject manager and doctoral student at the Department of Environmental and Earth Sciences of the University of Milan-Bicocca.

Once developed, “we believe that this method can be used both in a prognostic and diagnostic way”, Villa explains further. “Let’s think about the authorizations necessary for the placing on the market of products that contain an active chemical substance, such as a pesticide or a drug: all substances for which European legislation requires an environmental impact assessment. A company that needs to evaluate the potential risk before the product is used, in a prognostic way, could use this tool to obtain market authorization.” Or the pig method could be used “to map the quality of urban soils, also to measure its improvement over time, an objective indicated by the recently approved Nature Restoration Law. Or even to evaluate the quality of products such as compost”.