The famous “Tree of Life” (a branching diagram showing the evolution of species since the emergence of life on Earth) was not the first option Darwin chose to illustrate his theories. In fact, he was initially inspired by colonies of branching corals: Living corals (symbolizing recent life) grow atop large clusters formed over time by the accumulation of dead corals (symbolizing past life). He thus drew his first evolutionary sketches using this metaphor. He ultimately abandoned this concept in favor of the tree and its obvious connotations with religion, antiquity, art, and mythology, which at the time offered an image more accessible to the public. Yet in biology, the example of the branching coral is now regarded as a mathematical model. In particular, it helps resolve several practical and conceptual difficulties associated with the tree of life. This work is a tribute to Darwin’s research. Each piece of coral has been carefully selected and placed to symbolize the slow transformations that have been taking place in living organisms for 3.8 billion years.