Prediction in ecology and evolution

Abstract

Prediction is frequently asserted to be the sine qua non of science, but prediction means different things to different people in different contexts. I organize and explain this diversity by addressing five questions. What does it mean to predict something? To answer this question, I describe concepts of prediction as prophecy, diagnosis, history, repeatability, and fate. What are we trying to predict? Here, I describe how predictions vary along several axes: general to specific, qualitative to quantitative, relative to absolute, point to range, and continuous to discontinuous. Where do predictions come from? In this case, I focus on deductive versus inductive reasoning. How do we test predictions? The answer here is not straightforward and I discuss various approaches and difficulties. How good are predictions? Not surprisingly, it depends on what is being predicted and how we judge success. Importantly, I do not espouse a "best"way to approach prediction but, rather, I outline its diverse manifestations so as to help organize practical thinking on the topic.