Reproduction in Complex Life Cycles: Toward a Developmental Reaction Norms Perspective

Biological reproduction is a material process of intertwined, recursive propagule generation and development, assuming that development produces simple life cycles. Most organisms, however, have more or less complex life cycles. Here, I attempt to reconcile recent articulations of a reproducer account with traditional approaches to complex life cycles by generalizing genetic demarcation criteria for life cycle generations in terms of the scaffolded development of hybrid reproducers. I argue that scaffolding provides a general method for identifying developmental bottlenecks and suggests in turn a new way of understanding developmental reaction norms.