Countries are gathering Tuesday for a key U.N. nature conference in Montreal, aiming to broker a new global agreement to protect what’s left of Earth’s wildlife and natural spaces…Negotiators hope that the two-week summit, known as COP15, yields a deal that ensures there is more “nature” — animals, plants, and healthy ecosystems — in 2030 than what exists now. But how that progress is pursued and measured will need to be agreed by all 196 governments under the U.N. Convention on Biological Diversity (CBD).