解析库 > 填空经典1290题
Among wide-ranging animal species, populations at the edge of the species` range are frequently exposed to less (i)_____ and more variable conditions than those in other parts on the range. As a result, the animal`s abundance is often (ii)_____.
- lower at the periphery
- unaffected by habitat
- underestimated by researchers
favorable , lower at the periphery 显示答案