About Development

About Development is a freely available set of readings about what development is and how it works. How does development reliably produce organized living beings when there is no plan for the finished organism present at earlier stages? And how do we account for the differences among individuals that arise as they develop?

The readings draw on biology, psychology, neuroscience, and the history of ideas about development. They are organized into three parts and a coda.

What the Readings Cover

Part 1, Thinking About Development asks what we are trying to explain when we explain development. It considers changes across different timescales and places individual development within the recurring life cycles of organisms. The final reading examines the evolutionary emergence of multicellular development.

Part 2, The Making of Living Form takes up the question of how organized form arises. It begins with the historical debate between preformation and epigenesis, then considers Aristotle’s ideas about form and matter. Later readings examine the role of DNA and introduce developmental systems theory. The part ends by considering how development contributes to evolution.

Part 3, Bodies and Brains begins with the evolution of nervous systems in animals that were already moving and sensing. It then turns to the developing cerebral cortex. Studies of how cortical organization changes with bodily structures and patterns of sensory activity help us examine the relations between plasticity and constraint.

The Coda, The View From Where We Are returns to the broader questions running through the readings and considers their implications for understanding human lives. It also introduces the companion resource, Enacting Life, which explores living organization and its implications for cognition.

How to Read

The readings are arranged in a sequence, beginning with Development: A Wider View. Reading them in order will help with ideas that develop across the text, but individual readings can also be used independently.

No specialist background is assumed. Some readings nevertheless take up difficult questions, and it may help to return to an earlier discussion after encountering an idea in a different context. The historical material is part of the argument: older explanations of development often remain with us in the language we use today.

The Contents menu provides access to all the readings. On larger screens, an outline on the left links to sections within the current reading. Previous and Next links below each reading follow the sequence.

Source lists identify the works drawn on in the text. Some readings also include an Explore Further section for readers who want to pursue a question in more depth.

For the background to this project, see the Preface.