article-review-165

This unit is about ecology, the study of the interaction between living species. As we discussed in the unit lesson, all species are dependent on one another—even trees need birds to eat the insects that want to devour the trees. Some trees, like oaks, need squirrels to plant their acorns. Consequently, when you study a species in the Red List for this assignment, be aware that somewhere along the line, this species is important.