If Sharks Disappeared by Lily Williams. Roaring Brook Press, 2017. 9781626724136.
It says something about the power of art and storytelling (and a lot about Lily Williams) that she can make a complex idea like a trophic cascade (the drastic changes in an ecosystem resulting from the disappearance of an apex predator) clear and compelling to a young audience. As she shows, even though sharks can seem scary, they are absolutely necessary to the health of the oceans. They keep their prey populations in balance which in turn keeps their food sources in balance, and so on and so on, which extends to populations on land as well. The book ends with steps ordinary people can take to protect sharks that are vulnerable to extinction, from buying sustainably caught fish to creating their own shark art.