Origin of Life in Water

Numerous theories exist that explain the origin of life. One of these is the argument that life originated from water (Pollack, Figueroa, & Zhao, 2009). This arose from observations that water is a common feature shared by most living systems. In various living organisms, water forms a large constituent suggesting that the origin of life may have arisen in an aqueous environment. In one of the theories attributing the origin of life to an aqueous environment, life is contended to have begun beneath the frozen ocean (Pollack, Figueroa, & Zhao, 2009). Advocates of this hypothesis argue that the sun was not as luminous as it is today and the temperatures were very low. Such low temperatures occasioned a layer of ice that covered the ocean and protected the organic compounds below it from ultraviolet rays (Pollack, Figueroa, & Zhao, 2009). The protected compounds then underwent a series of reactions whose eventual outcome was living organisms (Pollack, Figueroa, & Zhao, 2009). Evidence supporting this hypothesis is the outcome of an experiment in which an ammonium cyanide solution was frozen for 27 years. The products from this experiment were purines and pyrimidines, which are nucleotides found in life elements such as DNA and RNA. The experiment offered proof that some aspects of living organisms may arise from frozen-ocean conditions (Miyakawa, Cleaves, & Miller, 2002).

Other researchers suggest that life began in the deep-sea vents. Such researchers argue that these vents produced hydrogen-rich molecules, which were concentrated by the rocky nooks (Martin, Baross, Kelley, & Russell, 2008). Mineral catalysts provided by the concentration of hydrogen-rich molecules facilitated critical reactions. Evidence supporting this hypothesis is the presence of ecosystems that are found in the ocean depths. Since various organisms such as crabs, bacteria, worms and some types of fish can survive in the cold environment in the depth of oceans, life is believed to have originated in this environment (Martin et al., 2008). Particularly, observations that such vents can support the existence of life in the absence of photosynthesis, offered support for this school of thought.

References

Martin, W., Baross, J., Kelley, D., & Russell, M. J. (2008). Hydrothermal vents and the origin of life. Nature Reviews Microbiology, 6(11), 805-814.

Miyakawa, S., Cleaves, H. J., & Miller, S. L. (2002). The cold origin of life: B. implications based on pyrimidines and purines produced from frozen ammonium cyanide solutions. Origins of Life and Evolution of Biospheres, 32(3), 209-218.

Pollack, G. H., Figueroa, X., & Zhao, Q. (2009). Molecules, water, and radiant energy: new clues for the origin of life. International Journal of Molecular Sciences, 10(4), 1419-1429.