What makes a theory a good theory

One lesson is that the reason a "good" theory should be testable, be coherent, be economical, be generalizable, and explain known findings is that all of these characteristics serve the primary function of a theory--to be generative of new ideas and new discoveries.

Explanation:

producers: apple trees, potatoes, carrots, grains, acorns, cabbage, grass, corn, lettuce

consumers: deer, mice, rabbits, chickens, squirrels, horses, worms, cows

predators: eagles, frogs, wolves, owls