National Geographic Primary Readers is a high-interest series of beginning reading books that have been developed in consultation with education experts. The books pair magnificent National Geographic photographs with lively text by skilled children's book authors across four reading levels. Over the course of their 70-year life-span, sperm whales will easily travel the circumference of the Earth in search of food and the need to breed and find a mate. Males will travel as far north as the Bering Sea and as far south as Antarctica in order to find enough food to sustain their ways of live - up to 700 squid a day! Along the way, these massive beasts battle 30-feet-long giant squids, and each other, to sustain their ways of life. Find out all about the life journey of sperm whales in this photographic book. Level 4: Independent readerPerfect for kids who are reading on their own with ease and are ready for more challenging vocabulary with varied sentence structures. They are ideal for readers of White and Lime books.