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Erle C. Ellis, University of Maryland, Baltimore County and James Watson, The University of Queensland

(THE CONVERSATION) Nature urgently needs our help. Wild creatures, from songbirds to butterflies and from primates to tortoises, are disappearing so rapidly that they could be lost forever together with the wild forests, grasslands and other habitats that long sustained them. We humans already use nearly half of all Earth’s land to sustain ourselves, and the most productive parts...