It is intuitive to conceptualize the environment shaping digital innovations as "ecosystems." However, the literature on digital innovation and ecosystems reveals silos and fragmentation surrounding the ecosystem concept despite the holistic approach that the ecological perspective implies. Acknowledging the limitations of ecological metaphors, in this conceptual paper, we recognize key similarities between natural and sociotechnical ecosystems and argue that digital innovation research may benefit from taking the ecological perspective seriously, not just as metaphors, but also as a theory. Specifically, the concept ecosystem can be applied to multiple levels of the digital innovation landscape, linking diverse entities such as processes, products, services, organizations, industries, and communities, as they draw on resources, including technology, attention, and knowledge, to create and realize the value of digital innovations. Further, we synthesize insights on natural and sociotechnical ecosystems to develop building blocks of a comprehensive ecology theory, as a multilevel platform to advance digital innovation research. This ecology theory of digital innovation ecosystems will also be able to pinpoint key levers that practitioners can shape strategically to realize the full potential of digital innovations for organizations, communities, and society.