Where does the reef start?

Excuse me, but could you elaborate on the question "Where does the reef start?" Are you referring to a specific coral reef, such as the Great Barrier Reef in Australia, or is it a more general inquiry about the formation and starting point of reefs in general? If it's a specific reef you're asking about, the starting point can vary greatly depending on the reef's location, geological history, and ocean currents. For instance, the Great Barrier Reef starts off the coast of Queensland, Australia, and extends for over 2,300 kilometers. However, if you're asking about reefs in general, they typically begin to form where sea levels are stable and coral polyps can grow and thrive. These polyps, tiny animals related to jellyfish, secrete a hard, limestone skeleton that eventually builds up to form the structure of a reef. Over time, as more polyps settle and grow, the reef expands and can eventually become a vast and complex ecosystem. So, in a sense, the "starting point" of a reef is wherever conditions are favorable for coral polyps to begin growing and building their homes.