问一个36套的问题

gloryming

练习7中第11题
For the following question, consider each of the choices separately and select all that apply  11. The author would be most likely to agree  with which of the following statements  about left-eyedness and right-eyedness in  the starry flounder? □A They are adaptive variations by the starry flounder  to environmental differences.
□B They do not seem to give obvious selective  advantages to the starry flounder.
□C They occur in different proportions in different  locations.
为什么不选A
这不是有原话么？
Biologists call this kind of gradual variation over a  certain geographic rang a ―cline‖ and interpret clines as   strong indications that the variation is adaptive, a  20 response to environmental differences.求解释！

zkh1991

你说的这句是 biologists的解释
后面作者也写了这些现象不能用adaptive很好的解释 所以肯定是不同意adaptive的说法的

gloryming

你说的这句是 biologists的解释
后面作者也写了这些现象不能用adaptive很好的解释 所以肯定是不同意adaptive的说法的

-- by 会员 zkh1991 (2012/12/3 19:04:11)

谢谢，看了你的解释我懂了。