"Why do roses have thorns? What are burs for? Theyre successful in keeping enemies and predators away! This superpowered defense is found on many kinds of plants, including well-known cacti! In this book, readers learn about these plants and find out the details of this cool defense. Concepts that are important for young science students, including survival and adaptation, ecosystems, and life cycles, are covered in the accessible main text, written especially for elementary readers"--.