Many are imperiled by loss of habitat, rising ocean temperatures and rural and urban areas’ demand for ever-increasing amounts of fresh water. Worldwide, the U.N. assessment found that of an estimated 8 million plant and animal species, about 1 million are on the brink of extinction because of the damage humans are inflicting on the Earth through global warming, logging, farming, mining and other activities. It was compiled by 145 expert authors from 50 countries. The full report won’t be made public until later this year, but a summary released Monday offered a damning assessment of human impacts over the last five decades.