The Biological Overview Effect: Our Place in Nature

Abstract While gazing at the Earth from orbit, some astronauts have described a cognitive shift known as the overview effect. Here we describe an analogous biological overview effect produced by looking at the tiny twig of humanity on the tree of life. We describe the increasingly precise phylogenetic tree of all life on Earth and how it shows us our place in nature. We discuss problems with this tree including the assumption of sexual isolation, purely vertical gene transmission and the dependence of LUCA (Last Universal Common Ancestor) on the completeness of the tree. We compile and present the most concise taxonomic overview of the evolution of our lineage from Archaea to humans.