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Masses of ocean plastic are providing artificial habitat (栖息地) for otherwise coastal species, according to a new study published in Nature Communications. The study’s authors observed floating water bottles, old toothbrushes and waste fishing nets. The possibility exists that species may be evolving to better adapt to life on plastic.

A decade ago, marine researchers believed coastal species could not survive a trip across the inhospitable open ocean. Yet Japan’s 2011 tsunami (海啸), which sent some 300 species of Asian marine life riding floating plastic garbage onto North American shores, disproved that assumption.

Ocean plastic is “creating opportunities for coastal species’ biogeography to greatly expand beyond what we previously thought was possible”, Linsey Haram, a researcher and co-author of the study, said in a report.

The concept of species-covered plastic may sound like the story of ocean species’ victory in spite of human pollution. But that’s not quite the case, explains Juan José Alava, PhD, an expert at the University of British Columbia. In addition to transporting non-native species to new habitats where they may become invasive and destructive, the plastic is “basically an ecological trap”, says Alava. “That’s because small species on the floating structure may attract bigger animals to come for food. When these creatures enter garbage areas for food, they run a high risk of eating and/or becoming caught in plastic and dying.”

While scientists have found some types of bacteria (细菌) are able to break down plastic, thereby cleaning up garbage, it’s unlikely that the marine animals will have any such effect. “The 2021 UN report was clear that the increasing plastic pollution is putting the health of all the world’s oceans and seas at risk,” says Alava.