动物园的存在引发伦理争议，是否应关闭？chinese同志男男版

　　Liz Bonnin presents a controversial and provocative episode of Horizon, investigating how new scientific research is raising hard questions about zoos - the film explores how and why zoos keep animals, and whether they need to change to keep up with modern science or ultimately be consigned to history. 　　Should zoos cull their animals to manage populations? Liz travels to Copenha... (展开全部)