Tinbergen's Four Questions
Behavior can be studied through mechanism, development, function, and evolutionary history.
The Mechanism: Niko Tinbergen distinguished four complementary questions about behavior: what causes it now, how it develops, what function it may serve, and how it evolved. They organize inquiry rather than provide four interchangeable answers.
The Philosophical Pivot: A cause at one level does not erase causes at another. Neural activity may explain how an action occurs while learning and evolutionary history help explain why that capacity exists.
The Horizon: Researchers can mistake an attractive evolutionary story for evidence about an individual animal. Separating questions helps prevent a plausible function from being treated as a proven history.
The framework also disciplines human explanation. A behavior can be biologically influenced without being inevitable, morally justified, or fully explained by its possible adaptive value.
A complete account need not reduce a life to one master cause; it can hold several levels of explanation together.
To explain a behavior is to ask which question you are answering, not to choose one cause for every level.
When I say I understand why someone acted, have I explained the mechanism, the development, the function, or merely chosen the story that feels most complete?