Over 100 years ago, before threats such as global climate change and ocean acidification were issues engrossing marine scientists, numerous tropical reef biologists began expressing concern that too much emphasis was being placed on coral dominance in reef systems. These researchers believed that the scientific community was beginning to lose sight of the overall mix of calcifying organisms necessary for the healthy function of reef ecosystems and demonstrated that some reefs were naturally coral dominated with corals being the main organisms responsible for reef accretion, yet other healthy reef ecosystems were found to rely almost entirely on calcified algae and foraminifera for calcium carbonate accumulation. Despite these historical cautionary messages, many agencies today have inherited a coral-centric approach to reef management, likely to the detriment of reef ecosystems worldwide. For example, recent research has shown that crustose coralline algae, a group of plants essential for building and cementing reef systems, are in greater danger of exhibiting decreased calcification rates and increased solubility than corals in warmer and more acidic ocean environments. A shift from coral-centric views to broader ecosystem views is imperative in order to protect endangered reef systems worldwide. 1. Introduction Around the globe, tropical to subtropical reef ecosystems are at risk. Environmental threats in the form of pollution, overfishing, alien species, global warming, and ocean acidification have led to the documented decline of coral communities in numerous marine ecosystems [1–9] and allowed macroalgal overgrowth to result in potentially nonreversible phase shifts in many locations [5, 10–14]. Management efforts will hopefully help to preserve and protect the imperiled ecosystems in which corals live; however, scientific terminology may be thwarting responsible conservation efforts by creating false representations of tropical to subtropical reefs in the minds of the general public and governmental management agencies. Many reef systems contain areas composed primarily of coral, but these areas are interspersed among other types of ecologically necessary, hard-bottomed, carbonate-accreting, reef areas that contain little to no coral. Recognition of the essential role these noncoral-dominated reef areas play to the overall health status and accretion of reef ecosystems will help to ensure that effective reef management measures are accomplished. 2. What Constitutes a Healthy Reef? Reef researchers from past decades described many healthy tropical
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