Why Mammals with a high rate of respiration need to have a high heart rate.

Because high heart beating rate can speed up the blood circulation in order to carry more oxygen for the body.

为什么哺乳动物具有高利率的呼吸都需要有一个高心率。
与呼吸作用的一种高速率的哺乳动物为什么需要有高心率。

Because they need to pump the blood to everywhere of the body to keep high level of blood and oxygen.

sorry。。ican not！