One look at the mammoth blue whale—one hundred feet long and as heavy as 40 elephants—leaves no doubt that only something as vast as an ocean could hold it. Yet whales, like other mammals, once lived on land, and weren’t always so big. Learn why these smart, social animals first took to water, and how they have adapted to aquatic life despite retaining the most basic need of land mammals: to exchange air through the lungs.
The Comprehension Questions are available to download as an RTF file. You can save the file to your desktop and open it in a word processing program.