The purple martin is a bird that eats insects. In terms of systems, why would the sudden elimination of this species be a problem? 1. The make up part of a negative feedback system that promotes insect population growth.

2. They make up part of a positive feedback system that promotes insect population growth.

3. They make up part of a negative feedback system that regulates insect population size.

4. They make up part of a positive feedback system that regulates insect population size.