G7 leaders were on Sunday urged to take urgent action to secure the future of the planet, as they finalised new conservation and emissions targets to curb climate change, and wrapped up a three-day summit where revived Western unity has been on show. Veteran environmentalist and broadcaster David Attenborough told the gathering of the world’s richest nations the natural world was “greatly diminished” and inequality was widespread. “The question science forces us to address specifically in 2021 is whether as a result of these intertwined facts we are on the verge of destabilising the entire planet?” he said. “If that...