Butterflies, often considered a “sentinel of change”, are on the move across every continent they inhabit, shifting to survive as global heating reshapes their environment. About one in 10 species have already expanded or contracted their geographic range, or shifted in altitude, according to a global study published in Nature Ecology & Evolution. “Butterflies are early‑warning indicators and are signalling a warning across the entire planet. About 80% of butterflies that shifted expanded their ranges, often moving into newly suitable areas as temperatures rise. Chris Farrow, the biodiversity officer at Yarra Valley Water, who was not involved in the global study, said the butterfly had “been making a comeback”.