Many animals live or work in groups. Some travel in large groups to protect themselves from predators. Other animals join together to hunt. No matter their size, groups are an important part of survival for many animals. Strength in Numbers: Animal Groups demonstrates the social structures of animal groups, exploring why they form and how they help different species. Aligned to Common Core Standards and correlated to state standards. Core Library is an imprint of Abdo Publishing, a division of ABDO.