The Silent Astronomer

The first organisms on Earth may have closely mimicked the geochemistry of our planet. The reasons as to why may be worded in the following manner, the first organisms needed to be (1) simple, and (2) adapt to the immediate, geochemical energetics. Examining seawater and other saline-type environments allows one to ponder upon the early geochemistry. How and why did life manage to gain a strong foothold upon the Earth? That “mystery” seems like magic to many of us. Life’s chemistry follows an evolutionary path—it found “the Darwin’s warm pond.” (And, where was that original warm pond? It truly is unknown.) Given what is known—the fossilized remnants, the chemical life forms that abound in the hot, sea vents (the black/white smokers), and other hyper-saline environments on our planet, there is a chemical commonality. As any (earthly) organism would do—it adapted in a manner that assured its survival.

via Wikipedia–Living fossils of Shark Bay, Australia.

Fig. 1  Stromatolites of Shark Bay are typical of Microbial Mattes which covered the primordial Earth.  (See the following URL:

http://www.sharkbay.org/default.aspx?WebPageID=228 )

Stromatolites of primordial Earth were primarily made of Cyanobacteria–that utilized Chlorophyll.

Fig. 2 via Wikipedia. White Smokers, (“White flocculent mats in and around the extremely gassy, high-temperature (>100°C, 212°F) white smokers at Champagne Vent.”) Original is from National Oceanic and Atmospheric Administration.

From the source description: “White smokers emitting carbon dioxide at the Champagne vent, Northwest Eifuku volcano, Marianas Trench Marine National Monument”

Source URL : http://oceanexplorer.noaa.gov/explorations/04fire/logs/hirez/champagne_vent_hirez.jpg

The earliest life forms did not utilize photosynthesis of which we are familiar. The organisms had an abundance of hydrogen, methane, sulfur, nitrogen, phosphorous, and an assorted lot of metals to utilize for its foodstuffs. (The carbon, oxygen, along with the eventual migration from a reducing atmosphere to an oxygenated atmosphere may have occurred as the consequence of the ground beneath our feet.) Although the migration from simplistic (?) life without utilizing chlorophyll (bacterial or plant) to the more familiar life forms is not readily understood. Three of the more abundant elements in the Earth’s crust; silicon, magnesium and oxygen needed to elicit a disequilibrium in the early organisms of life. Earth’s early organisms needed to adapt to an outside prompt (to become oxygen producers). The early organisms also “needed” to have “chlorophyll-like” chemistry in place so the organisms could readily adapt to produce oxygen. Evolution dictates that life’s footsteps be logically consistent—there seem to be no quantum leaps. 

Although the bio-origins of chlorophyll remain mysterious, it may be intimated that once it took hold upon the Earth it evolved in the reducing atmosphere to the oxygenated atmosphere. The earliest forms of chlorophyll seem to be bacterial—not so surprisingly—and we continue to search for how chlorophyll (that complex molecule) took hold.

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REFERENCES:

Primary Reference for post from the Journal –Astrobiology

Serrano, Paloma, Alves Forancelli, Michael Scott Chaffin, Jack Thomas O Malley-james, and Susan Carla Moreno. 2013. “From Cytoplasm to Environment : The Inorganic Ingredients for the Origin of Life” 13 (3): 294–303. doi:10.1089/ast.2012.0836.