Why no two corals look alike

In September we cut two pieces off the same brain coral and put one in raceway two and one in raceway three. Same water, same feed, four hundred millimetres of difference in depth.

Eleven months later they are not the same animal. The shallow one went green over red; the deep one stayed olive and grew a third faster. Neither is healthier. Neither is a mistake.

This is why we photograph individuals and refuse to write "same as pictured". The photograph is a fact about one animal on one day, and that is the most any photograph of a living thing can honestly be.