Species, speciation... and definitions

 









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Myths and Misconceptions

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Myths and Misconceptions - "The Linearity of Evolution" A common misconception of evolution is that it is a linear process, meaning evolution is progressive and insinuating that there is an "end goal" (or predetermined destiny) surrounding evolution. However, there is no true goal or even intention of evolution, it is better to think of this process as a means of trials and errors, causes and effects, or experimentations and adaptations.  My interest in this misconception of evolution is its direct usage in the history of entomology. Theodor Eimer, a German zoologist, published a paper in the Oxford Press in 1897 disapproving of the Darwin's theory (which theorizes  that variation occurs randomly among populations/species and that individual traits could be inherited by its offspring) in favor of orthogenesis. The term "orthogenesis" states that  variations in evolution follow a linear direction and are not randomized. In this paper, Eimer argues for ...
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Mutation and the Tree of Life

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 Mutation and the Tree of Life It is helpful to view mutations as any change in the DNA sequence of a cell! In the following depiction below, I illustrate a simplified example of different types of mutations (substitution, deletion, and insertion) using geometric patterns as a model for a cell's DNA sequence.  Now let's step away from viewing mutations through a geometric point of view as seen above and turn to look at the role of mutations in organisms, specifically in cocomonteres (a fictional organism)! As depicted above, the cocomonteres' exposure to parasites ultimately led to a mutation that caused a deformity, specifically an increase in their amount of limbs. A similar tragedy can be found with  Ribeiroia ondatrae in amphibians in the Western United States of America ( see here for more interesting information on the topic ). Based on the information given above, do you believe their mutation was beneficial, harmful, and neutral? In the case of growing excessive l...
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Convergence, Natural Selection, 'Survival of the Fittest'

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 Convergence, Natural Selection, 'Survival of the Fittest' Convergent evolution is the evolutionary relationship that occurs when organisms that are not closely related evolve similar traits or behaviors. Whereas, divergent evolution is the opposite of convergent evolution and occurs when two organisms share a common ancestor and evolve one or more traits and behaviors that make them different from each other. I have chosen the following example from "Improbable Destinies" to illustrate convergent evolution: different caffeine-producing plants. Using DNA comparisons, the author of this book built an evolutionary tree illustrating how coffee, tea, and cacao all occur on different branches of the phylogenetic tree. They are not closely related to one another. Coffee, tea, and cacao all convergently evolved due to them not being closely related based on genetic research but evolved similar traits or behaviors (in this case, caffeine production) as seen in the figure belo...
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