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Repeated evolution: Despite biochemically complex, C4 photosynthesis evolved repeatedly more than 60 times

Another miraculous stuff happened here, let me quote from a mainstream paper. Even the author finds the evolution of C4 photosynthesis ‘somewhat puzzling’ because it requires ‘dozen of genes’ to be changed simultaneously – the right way – in at least 60 evolutionary unrelated cases:

Both C4 photosynthesis and CAM have evolved independently multiple times from C3 ancestors. C4 species represent about 3% of flowering plant species (Sage et al., 2012), while CAM species represent about 6% (Silvera et al., 2010). The evolutionary path and the fact that it has been traversed multiple times independently are somewhat puzzling given that both pathways represent complex traits, which require multiple genes to change simultaneously. They require architectural adaptations—large storage vacuoles in obligatory CAM, Kranz anatomy, or highly specialized cell anatomy in C4—and biochemical adaptations with at least a dozen gene products altered in abundance and regulation.”

here is another mainstream scientist who seems to be surprised:

C4 is biochemically complex; to turn a C3 into a C4 plant appears to require modification of dozens of genes. Evolutionary theory suggests that complex adaptations should originate rarely, yet C4 has arisen in at least 66 lineages of angiosperms, appearing in 19 unrelated plant families.

lets not forget, it is not only the C4 photosynthesis… As the paper claims, the same miraculous stuff happened with CAM photosynthesis as well – also evolved many times repeatedly and independently in unrelated species …

But who cares ? Miraculous stuff happens all the time, mostly in biology …