Tree of life (science)


Tree of life (science)

:"See also Tree of life (disambiguation) for other meanings of the Tree of Life."
Charles Darwin believed that phylogeny, the ascent of all species through time, was expressible as a metaphor he termed the Tree of Life. The modern development of this idea is called the Phylogenetic tree.

Darwin's Tree of Life

An excerpt from Darwin's "The Origin of Species" (originally entitled "Phylogeny via Oogeny") explaining his views on the Tree of Life:

The tree of life today

The model is still considered valid for eukaryotic life forms. The earliest branch of the eukaryote tree yields four supergroups: Plants (green and red algae, and plants), Unikonts (amoebas, fungi, and all animals—including humans), Excavates (free-living organisms and parasites), and SAR (a recently identified main group, abbreviated from Stramenopiles, Alveolates, and Rhizaria, the names of some of its members) [ [http://www.apollon.uio.no/vis/art/2007_4/Artikler/The_Tree_of_Life Apollon: The Tree of Life Has Lost a Branch ] ] . Modern biologists now recognize, however, that the prokaryotes, the bacteria, have the ability to transfer genetic information between unrelated organisms. Recombination, gene loss, duplication, and gene creation are a few of the processes by which genes can be transferred within and between bacterial species, causing variation that’s not due to vertical transfer. The tree of life gives an incomplete picture of life at this level.

ee also

*Cladistics
*Common descent
*Phylogenetic tree

Footnotes

References

* Doolittle, W. Ford, and Bapteste, Eric. "Pattern pluralism and the Tree of Life hypothesis" PNAS, February 13, 2007, vol. 104, no. 7, 2043-2049. ( Reported At [http://www.physorg.com/news92912140.html PhyOrg.com] March 12, 2007 )

External links

* [http://tolweb.org/Life_on_Earth/1 Tree of Life Web Project] - explore complete phylogenetic tree interactively
* [http://tellapallet.com/tree_of_life.htm Tree of Life illustration] - A modern illustration of the complete tree of life.
* [http://www.sciencemag.org/feature/data/tol/ Science Magazine Tree of Life] - Sample tree of life from Science journal.
* [http://www.sciencemag.org/cgi/content/summary/300/5626/1691 Science journal issue] - Issue devoted to the tree of life.
* [http://www.geneticstimes.com/Research/Tiny_Genetic_Differences_Have_Huge_Consequences.asp] -Report on recent paper on "pruning" of the tree of life model.
* [http://demonstrations.wolfram.com/TheTreeOfLife/ The Tree of Life] by Garrett Neske, The Wolfram Demonstrations Project: "presents an interactive tree of life that allows you to explore the relationships between many different kinds of organisms by allowing you to select an organism and visualize the clade to which it belongs."


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