fig. 1 Gegenbaur 1870 hand homology
What is Homology?
ho·mol·o·gy
/hōˈmäləjē,həˈmäləjē/
In biology, similarity of the structure, physiology, or development of different species of organisms based upon their descent from a common evolutionary ancestor [1]. Homology is commonly thought of as structural evolution, such as limb homology. However, homologous structures can trickle all the way down to the gene level and sequence of amino acids. Homologous genes can be differentiated among organisms, as well as within a single organism. Orthologs, or orthologous genes, are a result of evolution from a common ancestor due to speciation. Genes that are paralogous arise as a result of a gene duplication event in the chromosome over the course of evolution[2].
/hōˈmäləjē,həˈmäləjē/
In biology, similarity of the structure, physiology, or development of different species of organisms based upon their descent from a common evolutionary ancestor [1]. Homology is commonly thought of as structural evolution, such as limb homology. However, homologous structures can trickle all the way down to the gene level and sequence of amino acids. Homologous genes can be differentiated among organisms, as well as within a single organism. Orthologs, or orthologous genes, are a result of evolution from a common ancestor due to speciation. Genes that are paralogous arise as a result of a gene duplication event in the chromosome over the course of evolution[2].
Ciona intestinalis (soft tunic ascidian)
Myotubularin ortholog (LOC100182371) Accession Number: ENSCINT00000015031.3 |
References:
fig. 1: https://commons.wikimedia.org/wiki/File:Gegenbaur_1870_hand_homology.png
[1] “Homology EVOLUTION.” Edited by The Editors of Encyclopaedia Britannica, Encyclopædia Britannica, Encyclopædia Britannica, inc., 8 Sept. 2016, www.britannica.com/science/homology-evolution.
[2] http://homepage.usask.ca/~ctl271/857/def_homolog.shtml
fig. 1: https://commons.wikimedia.org/wiki/File:Gegenbaur_1870_hand_homology.png
[1] “Homology EVOLUTION.” Edited by The Editors of Encyclopaedia Britannica, Encyclopædia Britannica, Encyclopædia Britannica, inc., 8 Sept. 2016, www.britannica.com/science/homology-evolution.
[2] http://homepage.usask.ca/~ctl271/857/def_homolog.shtml