David Bigatel, age 7, of Allentown, Pennsylvania, for his question:

How fast does a lion's heart beat?

The human heart beats about 70 times a minute, through most of the day. It beats faster when you run or do a lot of bodily exercise. And it slows down somewhat when you are asleep. The mighty lion, of course, is known as the King of Beasts. Most of the time, his heart beats only 40 times a minute. It speeds up a little when he dashes around and slows down somewhat when he dozes.

It seems that each kind of animal has a heart that beats at its own special speed. And some of the figures are surprising. The seagoing dolphin's heart beats 150 times a minute. But the heart of a little weasel beats up to 240. The giraffe beats 66 and the kangaroo beats 125. A tiger's pulse. rate is 64. And our handsome mountain lion has a heart beat that matches that of the King of Beasts    40 times a minute.