I first learned about Ernst Haeckel when I found his book Kunstformen der Natur online, in high-res PDF form. (You can now buy it in handy book form.) Using someone else's plotter and paper, I made some lovely posters for my apartment, but I never learned much about the man.
Last night, I watched Proteus, a 60-minute documentary about Haeckel. He was a scientist who wanted to be an artist, and vice-versa. He loved painting landscapes, but he was drawn, Goethe-like, to live in both worlds, art and science, and so he studied biology and used his extensive skill to record what he found.
He became a classic naturalist, traveling the world in search of every form nature took, but the documentary focuses on his decades-long obsession with radiolaria, the microscopic protozoa that leave uncountable varieties of mineral skeletons on seafloors throughout the world. Haeckel drew thousands of these, recording the minute variations in an impossibly beautiful, draftsman-quality hand (see above).
Haeckel became the primary proponent of Darwin's theories in Europe, and easily bridged his spiritual questions about the "first cause" with the wonder of nature he studied as closely as anyone ever could. In addition to his extensive printwork and literary output, Haeckel had some unadmirable, 19th-century ideas about race and politics. But he sure made pretty drawings.