<P> Tree diagrams originated in the medieval era to represent genealogical relationships . </P> <P> Phylogenetic tree diagrams in the evolutionary sense date back to at least the early 19th century . </P> <P> 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 . </P> <Table> <Tr> <Td> Part of a series on </Td> </Tr> <Tr> <Th> Evolutionary biology </Th> </Tr> <Tr> <Td> Key topics (show) <Ul> <Li> Introduction to evolution </Li> <Li> Common descent </Li> <Li> Evidence of common descent </Li> </Ul> </Td> </Tr> <Tr> <Td> Processes and outcomes (show) <Ul> <Li> Population genetics </Li> <Li> Variation </Li> <Li> Diversity </Li> <Li> Mutation </Li> <Li> Natural selection </Li> <Li> Adaptation </Li> <Li> Polymorphism </Li> <Li> Genetic drift </Li> <Li> Gene flow </Li> <Li> Speciation </Li> <Li> Adaptive radiation </Li> <Li> Co-operation </Li> <Li> Coevolution </Li> <Li> Divergence </Li> <Li> Convergence </Li> <Li> Parallel evolution </Li> <Li> Extinction </Li> </Ul> </Td> </Tr> <Tr> <Td> Natural history (show) <Ul> <Li> Origin of life </Li> <Li> History of life </Li> <Li> Timeline of evolution </Li> <Li> Human evolution </Li> <Li> Phylogeny </Li> <Li> Biodiversity </Li> <Li> Biogeography </Li> <Li> Classification </Li> <Li> Evolutionary taxonomy </Li> <Li> Cladistics </Li> <Li> Transitional fossil </Li> <Li> Extinction event </Li> </Ul> </Td> </Tr> <Tr> <Td> History of evolutionary theory (show) <Ul> <Li> Overview </Li> <Li> Renaissance </Li> <Li> Before Darwin </Li> <Li> Darwin </Li> <Li> Origin of Species </Li> <Li> Before synthesis </Li> <Li> Modern synthesis </Li> <Li> Molecular evolution </Li> <Li> Evo - devo </Li> <Li> Current research </Li> <Li> History of speciation </Li> <Li> History of paleontology (timeline) </Li> </Ul> </Td> </Tr> <Tr> <Td> Fields and applications (show) <Ul> <Li> Applications of evolution </Li> <Li> Biosocial criminology </Li> <Li> Ecological genetics </Li> <Li> Evolutionary aesthetics </Li> <Li> Evolutionary anthropology </Li> <Li> Evolutionary computation </Li> <Li> Evolutionary ecology </Li> <Li> Evolutionary economics </Li> <Li> Evolutionary epistemology </Li> <Li> Evolutionary ethics </Li> <Li> Evolutionary game theory </Li> <Li> Evolutionary linguistics </Li> <Li> Evolutionary medicine </Li> <Li> Evolutionary neuroscience </Li> <Li> Evolutionary physiology </Li> <Li> Evolutionary psychology </Li> <Li> Experimental evolution </Li> <Li> Phylogenetics </Li> <Li> Paleontology </Li> <Li> Selective breeding </Li> <Li> Speciation experiments </Li> <Li> Sociobiology </Li> <Li> Systematics </Li> <Li> Universal Darwinism </Li> </Ul> </Td> </Tr> <Tr> <Td> Social implications (show) <Ul> <Li> Evolution as fact and theory </Li> <Li> Social effects </Li> <Li> Creation--evolution controversy </Li> <Li> Objections to evolution </Li> <Li> Level of support </Li> </Ul> </Td> </Tr> <Tr> <Td> <Ul> <Li> Evolutionary biology portal </Li> <Li> </Li> <Li> Book </Li> <Li> Related topics </Li> </Ul> </Td> </Tr> <Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> </Table>

The type of decent that explains why all species are linked in a single tree of life