Ryan Nagelhout 
Sponges [PDF ebook] 

Sponges are possibly the world’s oldest animals. Their ability to survive and adapt in their surroundings is truly astounding, as is the fact that they’ve been on Earth for over 700 million years. This scientific guide covers the wild world of sponges, including their life cycles, feeding behavior, and more. Fact boxes provide quick, interesting facts, while a glossary and index complete a comprehensive reading experience. Colorful images take readers on a visual journey through sponge habitats, where there’s always something new to explore.