Tinbergen's four questions

Tinbergen's four questions, named after 20th century biologist Nikolaas Tinbergen, are complementary categories of explanations for animal behaviour. These are commonly called levels of analysis.^[1] It suggests that an integrative understanding of behaviour must include ultimate (evolutionary) explanations, in particular:

• behavioural adaptive functions
• phylogenetic history; and the proximate explanations
• underlying physiological mechanisms
• ontogenetic/developmental history.^{[2][page needed]}