Number of times that C4 carbon fixation (Hatch–Slack pathway) evolved independently

Range >65 times
Organism Biosphere
Reference Arrivault S et al., Metabolite profiles reveal interspecific variation in operation of the Calvin-Benson cycle in both C4 and C3 plants. J Exp Bot. 2019 Mar 27 70(6):1843-1858. doi: 10.1093/jxb/erz051 abstract & p.1844 left column bottom paragraphPubMed ID30773587
Primary Source Still CJ, Berry JA, Collatz GJ, DeFries RS. 2003. Global distribution of C3 and C4 vegetation: carbon cycle implications. Global Biogeochemical Cycles 17, 6-1–6-14 link AND Sage RF, Christin PA, Edwards EJ. 2011. The C4 plant lineages of planet Earth. Journal of Experimental Botany 62, 3155–3169 doi: 10.1093/jxb/err048 AND Sage RF. 2017. A portrait of the C4 photosynthetic family on the 50th anni-versary of its discovery: species number, evolutionary lineages, and Hall of Fame. Journal of Experimental Botany 68, 4039–4056 doi: 10.1093/jxb/erx005 PubMed ID21414957, 28110278
Method Primary source Sage et al. 2011, abstract: "Using isotopic screens, phylogenetic assessments, and 45 years of physiological data, it is now possible to identify most of the evolutionary lineages expressing the C(4) photosynthetic pathway."
Comments Abstract: "Low atmospheric CO2 in recent geological time led to the evolution of carbon-concentrating mechanisms (CCMs) such as C4 photosynthesis in >65 terrestrial plant lineages." P.1844 left column bottom paragraph: "C4 photosynthesis evolved independently >65 times in separate lineages among the angiosperms, and C4 species currently represent ~3% of terrestrial plant species and account for 23% of total terrestrial C gain (primary sources)."
Entered by Uri M
ID 116890