 In philosophy of biology, debates about reduction have focused on the question of whether and in what sense classical genetics can be reduced to molecular biology. Although other strands of discussion have been present (e.g., whether evolutionary theory is inherently anti-reductionist because of the principle of natural selection), philosophical debates increasingly address a wider array of domains (e.g., development, ecology, evolution, cell biology, and neuroscience), and include additional questions about the nature and status of interdisciplinarity, such as the integration of data or standards across biological fields. Questions about reduction in biology are pervasive throughout the history of philosophy and science. Many contemporary debates have historical analogues that reflect long-standing controversies about the legitimacy of reductionist research strategies and modes of explanation used by different life science subdisciplines.