Reading Metrics
Grade Level
Middle Grades (MG 4-8)
Book Level
5.1
Points
0.5
Fiction/Nonfiction
Nonfiction
Word Count
2981
Points per Word
0.000168
Page Count
48
Points per Page
0.010417
Series
Crabtree Chrome
Description
This book theorizes about the events that caused each of the five great mass extinctions, the first about 450 million years ago to the most recent 70,000 years ago.