雅思阅读辅导：代谢速率和寿命长短的关系

　　阅读段落

　　Animals which behave ‘frugally’ with energy become particularly old, for example, crocodiles and tortoises. Parrots and birds of prey are often held chained up. Thus they are not able to ‘experience life’ and so they attain a high life span in captivity. Animals which save energy by hibernation or lethargy (e.g. bats or hedgehogs) live much longer than those which are always active. The metabolic rate of mice can be reduced by a very low consumption of food (hunger diet). They then may live twice as long as their well fed comrades. Women become distinctly (about 10 per cent) older than men. If you examine the metabolic rates of the two sexes you establish that the higher malemetabolic rate roughly accounts for the lower male life span. That means that they live life ‘energetically’—more intensively, but not for as long.

　　段落大意

　　本段举例总结了代谢速率和寿命长短之间的关系：两者成反比。

　　阅读笔记

　　Animals behave ‘frugally’ become particularly old

　　E.g. chained up birds —not able to ‘experience life’ → high life span

　　Animals save energy live longer than those active

　　Higher malemetabolic rate → lower male life span
 

　　逻辑关系

　　1. 因果(逻辑连接词: THUS)

　　Parrots and birds of prey are often held chained up.

　　They are not able to ‘experience life’ and so they attain a high life span in captivity.