the type of decent that explains why all species are linked in a single tree of life
Tree of life (biology) The term phylogeny for the evolutionary relationships of species through time was coined by Ernst Haeckel, who went further than Darwin in proposing phylogenic histories of life. In contemporary usage, tree of life refers to the compilation of comprehensive phylogenetic databases rooted at the last universal common ancestor of life on Earth. The Open Tree of Life, first published 2015, is a project to compile such a database for free public access.