Please read and make a 1 paragraph comment to this post. References would be welcomed with the response.
The first step in bringing paleontology to the level of respect it has today was when it began considering fossils to be organisms rather than just dead things that were documented and then dismissed. Paleontology did not always ask questions regarding the fossils that were found but really just described their anatomy. With the publication of the textbook Principles of Paleontology, this all changed because for the first time a book about paleontology did not include any descriptions of fossilized vertebrates (Prothero, 1992).
Punctuated equilibrium challenged Darwin’s theory of evolution by arguing that evolution did not occur gradually but in sudden spurts following stasis. The gaps that are seen in the fossil record contribute to this theory because due to the lack of transitional fossils. The argument regarding this was that the gaps were not actually gaps but evidence for punctuated equilibrium. Goulde and Eldredge argued that the gaps are simply stasis until the next burst of evolution occurred which gave us the next set of fossils.
An example of gradualism that was found to be well documented was with protistans. The argument to this was that it happened because they are mostly asexual, have populations containing trillions of individuals and that their populations live in massive environments with no isolation such as the ocean (Prothero, 1992). There was also discovery of stasis among most species lasting millions of years. It was found that even in extreme environmental change, such as Ice Age, that species were able to remain stable despite this change. This research began the idea of species selection which is natural selection of species rather than of the individuals making up those species (Prothero, 1992).
The key ideas that emerged from this research would be stasis and hierarchy. Science began to try explaining why organisms were not seen evolving and put an importance on this subject. Russel Lande addressed these patterns of stasis by developing quantitative genetic models and was able to prove that these periods of stasis do not actually provide enough conflict with Darwin’s theory in order to actually challenge it. The other key idea that came from this research was hierarchy. This was an argument on what the cause of speciation was. The argument became that evolution was not occurring gradually and continually with the result of species but that due to extreme environmental change or isolation resulted in new species. This resulted in the idea that maybe environment played a larger role in evolution than science had originally believed (Lyons,).
References in addition to Prothero’s Article:
Lyons, S. L. (2011). Evolution. Abingdon, Oxon: Routledge.
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