Editing Common descent (section)

===Common biochemistry===

All known forms of life are based on the same fundamental biochemical organization: genetic information encoded in [[DNA]], transcribed into [[RNA]], through the effect of [[protein]]- and RNA-[[enzyme]]s, then translated into proteins by (highly similar) [[ribosome]]s, with [[Adenosine triphosphate|ATP]], [[Nicotinamide adenine dinucleotide phosphate|NADPH]] and others as energy sources. Analysis of small sequence differences in widely shared substances such as [[cytochrome c]] further supports universal common descent.<ref name=Knight>{{cite journal |last1=Knight |first1=Robin |last2=Freeland |first2=Stephen J. |last3=Landweber |first3=Laura F. |date=January 2001 |title=Rewiring the keyboard: evolvability of the genetic code |journal=[[Nature Reviews Genetics]] |volume=2 |issue=1 |pages=49–58 |doi=10.1038/35047500 |pmid=11253070 |s2cid=12267003 }}</ref> Some 23 proteins are found in all organisms, serving as [[enzyme]]s carrying out core functions like DNA replication. The fact that only one such set of enzymes exists is convincing evidence of a single ancestry.<ref name="theobald" /><ref name="Than2010">{{cite magazine |last1=Than|first1=Ker |title=All Species Evolved From Single Cell, Study Finds |url=https://news.nationalgeographic.com/news/2010/05/100513-science-evolution-darwin-single-ancestor/ |archive-url=https://web.archive.org/web/20100515123853/http://news.nationalgeographic.com/news/2010/05/100513-science-evolution-darwin-single-ancestor |url-status=dead |archive-date=May 15, 2010 |magazine=National Geographic |access-date=22 November 2017 |date=14 May 2010}}</ref> 6,331 [[gene]]s common to all living animals have been identified; these may have arisen from a single [[Animal#Phylogeny|common ancestor]] that lived [[Cryogenian|650 million years ago]] in the [[Precambrian]].<ref name="NYT-20180504">{{cite news |last=Zimmer |first=Carl |author-link=Carl Zimmer |title=The Very First Animal Appeared Amid an Explosion of DNA |url=https://www.nytimes.com/2018/05/04/science/first-animal-genes-evolution.html |archive-url=https://ghostarchive.org/archive/20220101/https://www.nytimes.com/2018/05/04/science/first-animal-genes-evolution.html |archive-date=2022-01-01 |url-access=limited |date=4 May 2018 |work=[[The New York Times]] |access-date=4 May 2018 }}{{cbignore}}</ref><ref name="NC-20150430">{{cite journal |last1=Paps |first1=Jordi |last2=Holland |first2=Peter W. H. |title=Reconstruction of the ancestral metazoan genome reveals an increase in genomic novelty |date=30 April 2018 |journal=[[Nature Communications]] |volume=9 |pages=1730 |number=1730 (2018) |doi=10.1038/s41467-018-04136-5 |pmid=29712911 |pmc=5928047 |bibcode=2018NatCo...9.1730P }}</ref>