1 in 4 Mammals Threatened, Study Says An “extinction crisis” is under way, with one in four mammals in danger of disappearing because of habitat loss, hunting and climate change, a leading global conservation body warned Monday. “Within our lifetime, hundreds of species could be lost as a result of our own actions,” said Julia Marton-Lefèvre, the director general of the International Union for Conservation of Nature, or I.U.C.N., a network of campaign groups, governments, scientists and other experts. Among 188 mammals in the group’s highest threat category — critically endangered — was the Iberian lynx, which has an estimated population of 84 adults and has continued to decline as its primary prey, the European rabbit, has fallen victim to disease and overhunting. The report, presented at the World Conservation Congress in Barcelona, formed part of a Red List of Threatened Species issued annually by the group. Jan Schipper, the director of the global mammal assessment for the I.U.C.N. and for Conservation International, an environmental group, said it was hard to draw a direct comparison with the last detailed survey on mammals, in 1996. New species have been identified, others discovered, and the criteria used to assess species have been made more broadly applicable across all animals and plants....