Timetree

A rectangular timetree of vertebrates [1]
A spiral timetree [2]

A timetree is a phylogenetic tree scaled to time.[3] It shows the evolutionary relationships of a group of organisms in a temporal framework.[3]

Therefore, if living organisms are represented, the branch length between the base of the tree and all leafs (e.g., species) is identical because the same time has elapsed, although extinct organisms can be shown in a timetree.[4]

As with a phylogenetic tree, timetrees can be drawn in different shapes: rectangular, circular,[3] or even spiral.[2] The only figure in Darwin's On the Origin of Species,[5] one of the earliest printed evolutionary trees, is a hypothetical timetree. Because the fossil record has always been tightly linked to the geologic record, evolutionary trees of extinct organisms are typically illustrated as timetrees.[6]

  1. ^ Hedges SB (2009). Vertebrates (Vertebrata). in The Timetree of Life, SB Hedges and S Kumar, Eds. (New York: Oxford University Press, 2009) P. 310 ISBN 0199535035
  2. ^ a b Hedges, SB; Marin, J; Suleski, M; Paymer, M (2015). "Tree of Life Reveals Clock-Like Speciation and Diversification". Mol. Biol. Evol. 32 (4): 835–845. doi:10.1093/molbev/msv037. PMC 4379413. PMID 25739733.
  3. ^ a b c Hedges SB; Kumar S (2009). Discovering the timetree of life. in The Timetree of Life, SB Hedges and S Kumar, Eds. (New York: Oxford University Press, 2009) P. 3-18 ISBN 0199535035
  4. ^ Marjanović, David; Laurin, Michel (2014-07-04). "An updated paleontological timetree of lissamphibians, with comments on the anatomy of Jurassic crown-group salamanders (Urodela)". Historical Biology. 26 (4): 535–550. doi:10.1080/08912963.2013.797972. ISSN 0891-2963. S2CID 84581331.
  5. ^ Darwin C (1859). On the origin of species by means of natural selection. (London: John Murray).
  6. ^ Benton MJ (2014). Vertebrate paleontology. Oxford, UK: Wiley-Blackwell. ISBN 978-111840755-4