Haeckel was, like Alexander von Humboldt before him, engaged in bringing together the - at that time, disparate - sciences of geology, evolution, zoology, embryology, physics and cosmology, and his newly coined "ecology," in the construction of a new, naturalistic worldview that brought all of these things together into a single explanatory story. He argued that the guiding principles for such a story would be the old Greek trinity of goodness, beauty, and truth. Many of the connections he made between various plant and animal organisms, and between the various sciences, were depicted in a number of his paintings and sketches. The most well-known of these can be found in his Kunstfbrmen derNatur. He sought in these drawings to sketch out the similarities in forms across many very different and very diverse species and in doing so challenged the dominant theological aesthetics of the Christian West at the time. This chapter analyzes some of these sketches/paintings and the way that he challenged three primary aesthetic categories: that between biotic and abiotic things in the world, that between plant and animal life, and that between humans and the rest of the animal world. It was from within these curious borders and crossings that Haeckel wondered most about constructing a naturalistic worldview that would fundamentally shift how we understood humans within the rest of the evolving planetary community.
