triphosphate (ATP), which became the universal storage of aerobic energy, becoming essentially spare energy for the cells to use(6). The energy within the molecules is stored within the phosphorus bonds to power cellular processes. The new cell itself was capable of reproducing asexually through binary fission, the process where a prokaryote splits into two (not to be confused with mitosis as it occurs in eukaryotes), with more cells being capable of carrying out metabolic reactions. The engulfed cell eventually became the mitochondria, known as the powerhouse of the cell. (7)

The engulfment of a cell though occurred more than once throughout history. Approximately 1.7 billion years ago, a cell engulfed another cell, and the smaller cell transformed into the chloroplast, an organelle containing chlorophyll with enzymes that can photosynthesise (convert carbon dioxide and water into oxygen and glucose). (8)

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Chloroplasts are found in plants and some bacteria, though through photosynthesis using light energy, the production of oxygen gas increased, and the early plant cells produced 10% of the oxygen in today’s atmosphere. The volumes of oxygen led to the planet becoming deadly as oxygen reacted with other greenhouse gases, changing the composition of the atmosphere and allowing less heat to be trapped, from which derives the snowball earth theory, claiming that the planet’s surface became almost entirely frozen 1.9 billion years ago. Afterwards, volcanoes pumped greenhouse gases back into the atmosphere, raising the temperatures that lead to the unfreezing of the globe.(9)

As the new microorganisms evolved through natural selection, adapting to the environment through mutations, species became much more diverse. Despite approximately 99.9% of all species that have existed throughout the past being extinct(10), The estimate of species nowadays ranges from 3 to 100 million. (11)

Studying the formation of the Earth expands our understanding of the origins of life, and it has the potential to discover extraterrestrial beings by providing insights into the conditions necessary for survival.

(1). May, A., & Howell, E. (2023, July 26). What is the Big Bang Theory? Space.com. https://www.space.com/25126-big-bang-theory.html
(2). M. (2023, June 13). How the Earth and moon formed, explained. University of Chicago News. https://news.uchicago.edu/explainer/formation-earth-and-moon-explained
(3).  Study suggests complex life was present on Earth 2.33 billion years ago. (2017, March 6). MIT News | Massachusetts Institute of Technology. https://news.mit.edu/2017/complex-life-eukaryotes-earth-233-billion-years-ago-0306
(4). Webb, P. (n.d.). 3.1 Origin of Earth and the Solar System. Pressbooks. https://rwu.pressbooks.pub/webboceanography/chapter/3-1-origin-of-earth-and-the-solar-system/
(5). Knowlton, N., & Jackson, J. B. C. (2013, January 1). Corals and Coral Reefs. Elsevier eBooks. https://doi.org/10.1016/b978-0-12-384719-5.00237-9

(6).“The Deadly Chemistry That Made Life Interesting - Realclearscience, www.realclearscience.com/video/2023/06/16/the_deadly_chemistry_that_made_life_interesting_941108.html#! Accessed 12 Dec. 2023.
(7). “Binary Fission.” Encyclopædia Britannica, Encyclopædia Britannica, inc., www.britannica.com/science/binary-fission. Accessed 12 Dec. 2023.

(8).  Eukarya | Definition, Characteristics & Domains - Study.Com, study.com/academy/lesson/eukarya-definition-characteristics-examples.html. Accessed 12 Dec. 2023.