Astroecology: Theory and Models of the Universal Structure and Distribution of Life.

Astroecology has been proposed as a scientific field to study the diversity, structure, and function of ecosystems on Earth and other worlds; it is increasingly important as new space-borne observatories expand the search for inhabited planets and moons. Recent work has highlighted the relevance of ecological concepts across hierarchical levels from organisms to biospheres. However, we still lack general predictions about how processes such as species interactions and tradeoffs scale to affect food-web structure, biodiversity patterns, and life-planet feedbacks. Ecological processes emerge from basic physical and biological constraints. They generate patterns in biodiversity, ecosystem structure, and energy flow that are replicated across ecosystems, biomes, and taxa. These patterns generate "ecosignatures"-large-scale spatial or temporal signatures that reveal not just life but aspects of its ecological organization. Astroecological models thus provide a theoretical foundation for biosignature interpretation, comparative planetary habitability, and the universality of ecology.