Theories about the evolution of photosynthesis are constrained by two evolutionary assumptions. Firstly, scientists assume that the early earth lacked free oxygen as this would make the chemistry for origin of life scenarios easier to achieve. Also, since any new organisms would very soon need a source of food (i.e. organic carbon), scientists suggest hopefully that photosynthesis originated early in the history of life (before many cells could starve.) But how long would it take for these elaborate molecular systems to develop?

One expert defined photosynthesis and its significance as “the only significant solar energy storage process of Earth and [it] is the source of all of our food and most of our energy resources.” [Robert E. Blankenship. 2010. Early Evolution of Photosynthesis. Plant Physiol. October 154(2): 434-438 See p. 434]. Obviously, the importance of this process cannot be overstated since life could not last long without a source of food.

When specialists compare organisms which exhibit the capacity for photosynthesis, they find a hodge-podge of variations rather than clear lines of descent with modification. Dr. Blankenship therefore suggests that different component parts of the process evolved separately [p. 3] and that what we see in organisms today is the result of extensive shuffling of component parts between bacteria via HGT (horizontal gene transfer) (this is the perennial evolutionary cop-out these days). [p. 2] That is why no pattern in various traits can be discerned. Six different phyla of bacteria (including cyanobacteria or blue green algae) exhibit photosynthetic abilities. Among eukaryotes, various kinds of algae and land plants are all able to photosynthesize. We see therefore that no evolutionary pattern can be seen for the origin of photosynthesis, so the experts are forced to assume that parts of the system exhibited separate origins.

The core of the photosynthetic hardware is the reaction centre. It is a multiprotein complex (maybe ~ 25-30 subunits) surrounded by an antenna of hundreds of chlorophyll molecules. All aerobic photosynthesizers have chlorophyll a. Green algae and land plants also have chlorophyll b. Depending upon the kind of alga, various other accessory pigments can be found in the antenna. Anaerobic but photosynthetic bacteria exhibit other types of the chlorophyll molecule.

Chlorophyll molecules are enigmas. They require 17 or more metabolic steps to complete the synthesis. What could possibly encourage this chemical synthesis to proceed when there was no particular use for the intermediate products? How could the process develop before there was even a use for chlorophyll? The early steps in the formation are identical to heme, a compound important in releasing energy from food. Although presumably the early syntheses of chlorophyll were initially all carried out under anaerobic conditions, now however for the cyanobacteria and eukaryotes, several steps in the synthesis require oxygen. Scientists therefore assume that some genes in the process were replaced by substitutes. The overall pathway, they suggest, remained unchanged while several component genes became completely different than in earlier versions.

The reaction centre and associated antenna are called a photosystem. Depending upon the molecules in the reaction centre, we find photosystem II in purple bacteria, type I in green sulphur bacteria and photosystems II and I in all oxygenic photosynthesis including cyanobacteria and algae and land plants. The reaction centres are so complex that scientists speculate that the core complex developed only once and subsequently underwent major changes. The basic three-dimensional protein structure with associated molecules stayed the same, but the amino acid composition (and DNA sequences) of the molecules changed. [This is a popular evolutionary theory these days, that a protein shape stayed the same while its underlying chemical composition changed entirely. But if the biochemistry is different, how can they say that the molecules are similar, no matter what the outward appearance may suggest. What this situation suggests is the use of a common blueprint.]

The accessory pigments in various photosynthesizing organisms are quite different from each other. The experts conclude that new pigments originated multiple times. [But developing a pigment from scratch that will react to the correct wavelength of light, is no mean trick.] The experts still conclude that the reaction centre/ photosystems only originated once and then underwent complex development. Nobody however has any plausible idea as to how the cyanobacteria (blue green algae) and all eukaryotic photosynthesizers came to require two photosystems. The specialists also have no idea how oxygen came to be a byproduct from capturing light energy.

It is evident that evolutionary speculations cannot explain how such elaborate cellular machinery was ever assembled, nor how the components came together, nor how they work, nor how the whole system appeared spontaneously at a time of low to zero food/energy resources. The more we learn about photosynthesis, the more elaborate we find the process to be. Evolutionary explanations are obviously completely inadequate. God’s plan was perfect. He created plants (the primary producers) ahead of the animal consumers. There never was a time when God did not provide for His creatures. Nothing, not even photosynthesis is too hard for our God to create!

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