Top-Down Causality

Advances in genome sequencing technology have allowed the molecular blueprint of all living things to be traced back to the emergence of the ribosome. From this molecular digital-to-analog converter radiated all cellular life. But we also learned that this blueprint is both far simpler and much more complex than we ever imagined. While the number of human genes is far fewer than we expected, our knowledge of the remarkable epigenetic coupling with the environment and extensive lateral gene transfer throughout evolution has radically changed our view of molecular heredity.

To truly understand this system, the range of diverse chemistry that makes it possible, and the extent to which alternate chemistries may have been discovered and abandoned, we must now map the molecular underpinnings of life on Earth today. The environment organisms live in—either here or on another planet—affects their growth, as does the diversity of organisms living together side by side. The nature of these relationships raises questions about how the environment affects and even alters genes, how the diversity of populations of organisms influences biochemical innovation, and how such interactions among organisms influence and shape environmental dynamics. The answers to these questions will significantly impact future survival.