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Evolution of Evolutionary Theories

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Published: 23rd Sep 2019 in Biology

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The Evolution of Evolutionary Theories: a macro and micro look at adaptation

Research Question: How does the evolution of cells, specifically from prokaryotic to eukaryotic, provide insight into the role of energy in evolution?

Table of Contents
 

Section 1: Introduction

Section 2: Energy of Prokaryotic Vs Eukaryotic Cells

Section 3: Implications

Section 4: Conclusion

Section 5: The Future of Evolutionary Theory

 

Section 1: Introduction

 

Our understanding of evolution is rapidly changing. The most familiar and dominant theory in evolutionary sciences is the theory of natural selection developed by Charles Darwin in 1859 when he published On the Origin of the Species. He wrote that the diversity of species was the result of genetic mutations over time that gave a species competitive advantages. The process of genetic mutations might take generations as the new genes were passed down to new generations.[1]

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When On the Origin of the Species was published, Darwin’s theory was considered controversial. Since then, the theory has been widely supported and therefore widely accepted in the scientific community and the general population. The primary principles of natural selection have even been recreated and simulated. This 2018 Nobel Prize winners in Chemistry, for example, directed enzyme evolution in a way that is now used in making everything from biofuels to synthesizing medical drugs.[2]

But in the last two decades, there has been a significant number of new theories and significant research milestones that have added to our understanding of the causes of biological life on earth as we understand it.

There is an increasing interest in various factors being responsible in part for the biological diversity. For example, self-organization, which is the concept that order can arise from local interactions between parts that are initially disordered. Spontaneous self-organization has been identified as important to shaping living organisms on the molecular level and within morphogenesis: the biological process that causes an organism’s shape.[3] Other scientists factor in the essential role of energy such as from the sun in driving biochemical reactions in cells. Their systems are considered self-catalyzing, developing their living systems through a constant source of energy rather than just self-organizing.[4]

Neither of these more recent developments in understanding of the evolutionary process replace the notion of natural selection but they add to Darwin’s dominant theory and explain how changes and adaptation in living organisms might happen more quickly than previously thought and with more complexity, in other words, there are more forces and factors at play and less intentionality. Life also exists, not just out of survival of the fittest, but also self-organization.

One biophysicist in particular working today, Jeremy England, uses statistical physics to explain the spontaneous emergence of life.England calls this process “dissipation-driven adaptation.”[5]

His theories have even been tested on computer simulations.

Like many other scientific breakthroughs, Jeremy England’s began with observation; and then a question. He often spent time by the beach and he noticed the variety of creatures that lived there. He began to wonder why there were so many types, shapes and sizes of organisms. He thought natural selection would account for fewer types of creatures honed for survival rather than the multitude of creatures like snails and jellyfish that he encountered. One hundred and fifty years earlier, Darwin had travelled to the Galapagos and walked among the animals and began his insights into the cause of life by similarly observing and asking how the different types of finches developed.

When we combine Darwin’s substantiated claims of natural selection with Jeremy England’s emerging theories of dissipation-driven adaptation we are able to get a fuller picture of the cause of life.

England’s research is focused on how evolution is the constant change in how biotic creatures react to energy. For example, the force of the sun’s heat injects into the system of a jellyfish which is forced to redistribute that energy and dissipate that energy while maintaining its systems of existence. This includes cause and effect as well as dissipation and conservation. This is what often drives change in living creatures. This is seen in changes between the animal kingdoms, for example. The mitochondria in eukaryotic cells is an evolutionary example of such processes. This can also be compared to prokaryotes and their lack of such functions and organelles, like the mitochondria. Understanding the evolution of these cells can provide insight on what role energy plays in evolution. For this investigation, mitochondria will be the focus despite its similar counterpart, chloroplasts.

In order to investigate the role of energy in evolution, the terms must first be defined. Energy exists in different forms but is neither created nor destroyed; it simply converts to another form.[6] Energy can take different forms such as kinetic, thermal, chemical, and potential. Many of which are utilized in the cell. Energy is important to evolution; “life is the harnessing of chemical energy in such a way that the energy-harnessing device makes a copy of itself”[7] In short, the capacity to do work takes many forms in type of energy and ways of reacting to it, which affects the direction taken in evolution and promotes the change in the first place.

Charles Darwin’s theory of evolution does not heavily address energy and its role, instead it emphasizes a genetic heredity and natural selection. When it comes to processing energy, heritable physical or behavioral traits are results of the best, or most efficient given what has already evolved, ways to react to energy being passed down from generation to generation. It is important to mention that it is the most efficient given what has been evolved because natural selection will sooner result in the neglect of a trait no longer needed than the correction of that trait. Evolution is building upon the past and changing what has already been evolved. The evolution from prokaryotic cells to eukaryotic cells through endosymbiosis is described by this theory but the role of energy is important as well.[8] However, both interrelated aspects- genetic and energetic- are seen in the evolution and change from prokaryotic cells to eukaryotic cells and how they process and benefit from energy. This will allow the two aspects of evolution to be compared in one instance: the evolution of eukaryotic cells.

This cell’s evolution in summation is the result of the endosymbiosis between prokaryotic and eukaryotic cells, which consisted of bacteria living inside of larger cells creating a symbiotic relationship. This is called the Endosymbiotic theory of eukaryotic cell evolution. Their evolution is hard to map because there are no cells with a “medium” level of complexity, however, the mitochondria, with their own set of DNA, also show that the endosymbiosis theory is supported.[9] Assuming this theory is true, the success of the energetic processes resulted in the natural selection of these organisms and eventually lead to the eukaryotic cell.

With these differences identified in eukaryotic and prokaryotic cells as well as Darwin’s theory of evolution and energy in evolution, how then, do the differences in how prokaryotic and eukaryotic cells deal with energy provide insight into the role of energy in evolution?

Section 2: Energy of Prokaryotic Vs Eukaryotic Cells

 

To begin the comparison between prokaryotic cells and eukaryotic cells, prokaryotic cells are do not have a true nucleus or many of the other cell organelles that eukaryotic cells have such as the mitochondrion[10]. Prokaryotic organisms consist of a single prokaryotic cell, which makes energy for themselves often times through glycolysis in the cell’s cytosol or cell wall. Without mitochondria however, they use enzymes attached to the cell membrane to break down their consumed organic compounds to produce ATP.[11] It is this prokaryotic or bacterial cell or bacterium that was engulfed by an Archaeon resulting in a symbiosis relationship and eventually evolving into an entirely new type of cell with new characteristics, like mitochondria for the production of energy in the form of ATP.

The structures and characteristics of a eukaryotic cell must also be analyzed, as well as in respect to energy. One characteristic is that internal compartments, membranes and cytoskeletons organize the cell’s contents.[12] Eukaryotic cells are the result of the reproduction of the older characteristics of the original symbiotic pair: the two bacteria. After generations of this reproducing as such, the eukaryotic cell came to be allowing life to take a much more complex form and multicellular life, and therefore resulting in much more complex ways of reacting to energy, such as the utilization of millions of cells to process far greater amounts of energy through assimilation than was once possible due to the lack of evolved processes. The consumption of nutrients in more complex organisms, such as humans, is far more involved with thousands of more processes than what was necessary two billion years ago for the first eukaryotic cells to consume and utilize their own energy.[13]

The distinction between eukaryotic and prokaryotic is so great that “it is considered to be the most important distinction among groups of organisms.”[14] The difference between the two also shows in the eukaryotic cell’s resulting organisms, as organisms become much more complex and handle energy in a much more complex way through the further evolution of eukaryotic cells. For example, the many functions of an animal’s metabolism and how it processes energy. Other notable differences include the nucleus and its genetic information and DNA, which are present in eukaryotic cells as well as their larger size, complexity, organelles, number of chromosomes, and an endoplasmic reticulum. Perhaps noteworthy, is one of the few similarities shared by eukaryotes and prokaryotes. The presence of ribosomes, which are responsible for the creation of proteins. This shows one of the few ways in which eukaryotic and prokaryotic cells similarly process energy. In this case, how they process external resources such as sunlight and organic food molecules.[15] The similarities in which they react to energy -creating chemical energy from available resources- also shows support for the theory of Endosymbiosis in that eukaryotic cells may have evolved from prokaryotic cells. However most important to this investigation are their differences in energy processes and methods.

How does each type of cell process and deal with energy? How is this related to the cell’s specific evolution? As discussed earlier, evolution and energy are responsive to one another. The evolution of prokaryotic to eukaryotic cells, specifically the greater complexity in energy processes as shown in the mitochondria, is an example of an evolutionary response to energy. In other words, changes were made in a certain type of cell because of the way in which energy was used as an input and output. These processes, in summation are the use of oxygen to form ATP for other cellular functions. It is how they gain the ability to do work. This includes glycolysis, the Krebs Cycle, and the Electron Transport Chain. Mitochondria can produce ATP from various energy molecules such as sugars and fatty acids through biochemical reactions.[16]

On the other hand, although some prokaryotic cells are able to use more processes than just glycolysis, most use this as their only source of energy production.[17] Prokaryotes themselves have many adaptable features such as how they process energy which are of a wide variety: Eukaryotic cells are only able to process energy through photosynthesis and respiration while prokaryotic cells are able to process energy through photosynthesis, respiration, nitrogen fixation, and denitrification.[18] Prokaryotic cells can also create ATP but they use mechanisms on their membrane and cytoplasm rather than using mitochondria. This may also explain the small and simpler characteristics of the prokaryotic as opposed to the eukaryote and eukaryotic cell. However, the external source of the energy is different for many prokaryotes and prokaryotic cells. The change in organism and complexity can be attributed to how the cells process energy. When eukaryotes are able to more efficiently dissipate, use, and produce energy, they are able to produce more complex organisms. This contrast can be seen in comparison to some prokaryotes in the same form as they were billions of years ago. This is not to discredit their role in energy processes as they are vital to many energy chains, however, the role of energy can be seen through their evolution and changes over time.

The history of the prokaryotic cells evolution to the eukaryotic cells evolution involves the Endosymbiosis theory. There are some issues with the theory including when and where the nucleus appeared in eukaryotic cells, and a characteristic required for such symbiosis not found in Archaea. Nonetheless there is much support for the theory. The mitochondria, membranes, and chromosomes to name a few. These especially support the idea of the mitochondrion originally acting as its own organism. The theory begins with the engulfment of unicellular organisms eventually resulting in these characteristics and causing a greater and more efficient generation of energy. [19] Chloroplasts also go to show that, with a different type of bacteria acting as symbiont, new efficient ways can be evolved to handle energy as seen in photosynthesis.

What does this difference in energy mechanisms say about energy in evolution? With more complex mechanisms and systems there becomes an increase in adaptability. This is also seen in the mitochondria as there are significantly greater amounts of ATP available with such evolutions, which makes it easier for an organism to adapt. This is also true because at least with living cells, oxygen is not necessary for energy production. This multitude of processes can support an organism in a variety of environments, which also promote evolution as this helps a species avoid extinction through natural selection. Some specific differences lie in just the location of the enzymes. Whether they are on the cell membrane or mitochondria can make a difference.[20] The greater production of energy lying in enzymes on the mitochondria as a result of the original symbiotic pairing between the bacteria and Archaea.

 

Section 3: Implications

Ultimately, the role of energy in evolution is that of a factor that drives change and adaptation in a species through the adoption of methods that best handle the energy in an efficient way, often times dissipating it. Systems become more complex with a higher capacity for variation and amounts of energy in general.

The release of energy from sugar is an example of one of the many ways eukaryotes neutralize energy when it is in contact with a cell. This example of how eukaryotes handle energy and try to dissipate it often shows its effectiveness in neutralization.[21]

Since eukaryotes are able to handle larger amounts of energy they also tend to live longer. Multicellular organisms with eukaryotic cells tend to have a longer life span.[22] Eukaryotic cells are able to dissipate, generate, and convert energy in very large quantities. These features of the eukaryotic cells from endosymbiosis was also a reaction to energy. How energy can be efficiently handled in an organism is what drives its evolution. The more complex structure of the eukaryotic cells also have benefits over their mitochondria-less counterpart, the prokaryotic cell. These include the controlled and complex movements of their filament. While prokaryotes do have this feature, it is not as efficient because of its lack of control or direction.[23]

 

The role of energy in evolution can be investigated through the comparison of energy systems in prokaryotic and eukaryotic cells and how each cell type’s respective characteristics contribute to the insight of this role. This can be looked at through analyzing the results of the evolution of the respective cell types and what their differences are. They show that efficiency, dissipation, and adaptability, which includes the ability of eukaryotes to not always need oxygen, lead to more complex changes and as a result, evolution and change. Through this it can be said that evolution is driven by an organism’s method of dealing with energy. The increasingly complex systems of dissipating energy in reaction to the impact of outside energy forces play a key role in evolution. The efficient energy production is not merely an evolutionary advantage, but processing, utilizing, and expending the energy injected directly and indirectly from outside sources such as the sun by developing spontaneous, self ordering complex dissipation systems is also a hallmark of staying alive to procreate and points to the possibility of self-ordering replication.

A recent study also shows that generational mutations are not required for evolution and adaptation. Energy can have an immediate effect on organisms and their DNA. Jeremy England’s research presents a similar concept in which evolution- or rather the change of an organism in reaction to energy for the sake of efficiency and dissipation- takes place within one lifetime. These changes take place through epigenetics, or traits that originate from cellular proteins that are in charge of access to DNA. as opposed to changes through genetics.[24] These proteins respond to changes in the environment and the energy in the environment of the cell. The study was conducted on Archaea due to their simplicity and similarity to eukaryotes where acid resistance became a characteristic.[25] These Archaea show a change in reaction to energy within one lifetime challenging Darwin’s original idea of generational evolution.

Section 4: Conclusion

These differences, mostly the mitochondria in eukaryotic cells being investigated, result from the endosymbiosis of bacteria and Archaea resulting in a new type of cell. The symbiotic relationship enhanced energy efficiency and quantity resulting in the morphing of the eukaryotic cell. Now, with more complex features, compartments, and organelles, like the nucleus and flagella, more is possible. In parallel with the two cells that originally merged, the grouping of eukaryotic cells into multicellular organisms results in even more complex, efficient and high energy machines effectively able to process and produce energy. An example of such organisms being humans. Another example being the ability to conserve energy in controlled movements of flagella in eukaryotic cells, as opposed to the constantly moving flagella of the prokaryotic cells. Eukaryotic cells tend to be larger and can process much higher amounts of energy as well as becoming larger organisms because the endosymbiosis of the Archaea and bacteria allowed for there to be a much higher yield of ATP. The processes, as they get more complicated also allow for a wider variety of energy types like kinetic and chemical. Prokaryotes also have a variety of methods to taking in energy themselves. This shows how although the complexity and size is not at the same level as that of eukaryotic cells, it is still extremely effective and efficient in ecological systems as a whole and how larger chains react to and deal with energy. This complexity of energy methods in the prokaryotes also show that variety can result in adaptability as well as the role of energy in evolution as how the prokaryotic cells and eukaryotic cells each deal with energy results in change and evolution.

In this investigation there may have been possible errors or inconsistencies. These could have resulted from the lack of comparison between different types of bacteria, prokaryotic cells, Archaea, and eukaryotic cells such as plant cells. For example, there are multicellular prokaryotes. There also maybe a lack of discussion regarding the different types of prokaryotes include photosynthetic prokaryotes, heterotrophic prokaryotes, and autotrophic prokaryotes.

Section 5: The Future of Evolutionary Theory

 
At some point in the history of the world, life may have formed from no life. The same physical principles that shaped the earliest living organisms are probably still at play in the formation of life today. While the origins of life are still a mystery many agree that great progress will be made in the next few years and it will shed light on evolution today. While dissipation-driven adaptation of matter has been statistically proven through mathematical models, there is no readily accessible example of this type of self-ordering to point to in nature–yet. “Many examples could be right under our nose, but because we haven’t been looking for them, we have not noticed them,” said Jeremy England.[26]


When we consider the future exploration of the causes of life we can assume that the direction scientists take will largely depend on how we define life in the first place. One definition being that as long as something is able to self-organize and reproduce, it is considered alive. For example, if molecules in a glass are able to reorganize upon being met with a high-pitched sound in order to maintain shape, would the “alive” be considered a fit label for the glass?


Will future human life be a hybrid of biology/technology or will we be shaped in response to our next host planet? The outcome is less understood than the evolutionary process that will get us there. As our understanding of evolution increases, it is becoming evident that there is more to it. It is a mix of Darwin’s natural selection, generational evolution, events of evolution within one lifetime all of which become responses to energy at efficient levels. While a complete model shedding light onto the causes shaping life remain elusive, we are getting closer to a full understanding of the causes of life each day.

Bibliography

 

 

  • “Brian Goodwin.” Wikipedia, Wikimedia Foundation, 30 July 2018, en.wikipedia.org/wiki/Brian_Goodwin.

 


[2] Guarino, Ben. “Nobel Prize in Chemistry Goes to Three Scientists Who Harnessed ‘the Power of Evolution’.” The Washington Post, WP Company, 3 Oct. 2018, www.washingtonpost.com/science/2018/10/03/nobel-prize-chemistry-goes-three-scientists-who-harnessed-power-evolution/?utm_term=.7e8b99f1b06a.

[3] Kaufman, Stuart. At Home in the Universe

[4] Fox, Ronald F. (December 1993). “Review of Stuart Kauffman, The Origins of Order: Self-Organization and Selection in Evolution”. Biophys. J. 65 (6): 2698–99. Bibcode:1993BpJ….65.2698F. doi:10.1016/s0006-3495(93)81321-3. PMC 1226010.

[5] “Brian Goodwin.” Wikipedia, Wikimedia Foundation, 30 July 2018, en.wikipedia.org/wiki/Brian_Goodwin.

[6] “Energy.” Biology Online, www.biology-online.org/dictionary/Energy.

[7] Lane, Nick, et al. Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 19 July 2013, www.ncbi.nlm.nih.gov/pmc/articles/PMC3685456/.

[8] “From Prokaryotes to Eukaryotes.” Relevance of Evolution: Medicine,
evolution.berkeley.edu/evolibrary/article/_0/endosymbiosis_03.

[9] “How Did Complex Life Evolve? The Answer Could Be inside Out.” BMC, www.biomedcentral.com/about/press-centre/science-press-releases/28-oct-2014.

[10] “Prokaryotic Cell – Definition, Structure, Characteristics and Examples.” Biology Dictionary, Biology Dictionary, 29 Apr. 2017, biologydictionary.net/prokaryotic-cell/.

[11] “How Do Prokaryotes Obtain Energy?” Enotes.com, Enotes.com, www.enotes.com/homework-help/how-prokaryotes-obtain-energy
-627216.

[12] “Eukaryotic Cell vs Prokaryotic Cell.” Mountain Bike vs Road Bike – Difference and Comparison | Diffen, www.diffen.com/difference/Eukaryotic_Cell_vs_Prokaryotic_Cell.

[13] Cooper, Geoffrey M. “The Origin and Evolution of Cells.” Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 1 Jan. 1970, www.ncbi.nlm.nih.gov/books/NBK9841/.

[14] “Eukaryotic Cell vs Prokaryotic Cell.” Mountain Bike vs Road Bike – Difference and Comparison | Diffen, www.diffen.com/difference/Eukaryotic_Cell_vs_Prokaryotic_Cell.

[15] “Eukaryotic Cell vs Prokaryotic Cell.” Mountain Bike vs Road Bike – Difference and Comparison | Diffen, www.diffen.com/difference/Eukaryotic_Cell_vs_Prokaryotic_Cell.

[16] Nature News, Nature Publishing Group, www.nature.com/scitable/topicpage/eukaryotic-cells-14023963.

[17] “Prokaryotic Cells.” Basic Biology, basicbiology.net/micro/cells/prokaryotic-cells.

[18] “Prokaryotic Cells.” Basic Biology, basicbiology.net/micro/cells/prokaryotic-cells.

[19] “Difference between Unicellular Organism and Multicellular Organism.” Difference between Bryophytes and Pteridophytes, www.majordifferences.com/2013/10/unicellular-organism-vs-multicellular.html.
 

[20] Lane, Nick, et al. Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 19 July 2013, www.ncbi.nlm.nih.gov/pmc/articles/PMC3685456/.

[21] Nature News, Nature Publishing Group, www.nature.com/scitable/topicpage/cell-energy-and-cell-functions-14024533.

[22] Difference between Bryophytes and Pteridophytes, www.majordifferences.com/2013/10/unicellular-organism-vs-multicellular.html.

[23] Moore, Sarah. “The Major Structural Advantage Eukaryotes Have Over Prokaryotes.” Sciencing, 21 Nov. 2017, sciencing.com/major-structural-advantage-eukaryotes-over-prokaryotes-14989.html.

[26] Wolchover, Natalie. “A New Physics Theory of Life.” Scientific American, 28 Jan. 2014, www.scientificamerican.com/article/a-new-physics-theory-of-life/.
 

 

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