Summary
This paper aims to summarize the main theses, ideas, and concepts from two research articles. First, the article by Snider and Brimlow (2013), which investigated the processes and dynamics of population growth in terms of the essential meaning of such studies, was selected. Second, the article by Vandermeer (2010) was studied, and the author sought to explore the concept of exponential population growth under upper-bound conditions as thoroughly as possible. Thus, both articles in the present work were based on population dynamics and approached the study of this phenomenon differently.
Snider and Brimlow’s Study
The work of Snider and Brimlow (2013) begins with a functional definition of why studying population dynamics makes sense. In short, the authors cite the importance of prediction, managing population biodiversity, and analyzing complex ecosystem connectivity as answers to this question.
The second concept their paper describes is exponential growth – the scientists explain the mathematical and physical logic of such growth in some detail and with examples, pointing out that population size is a predictor for exponential growth. It is also reported that this form of population dynamics is not uncommon in natural settings, particularly in relation to bacteria. The authors then discuss the factors that influence population fluctuations in natural ecosystems, noting that each population has limits to growth determined by a complex combination of natural environmental predictors.
The limitations of exponential growth are also discussed. As population size increases, certain factors begin to limit growth, including the inability to provide food for all members of the growing population and increased competition for survival. Dynamic population fluctuations can be driven by seasonal changes or by biogenic interactions between species. At the end of their paper, the authors extrapolate their findings to populations but do not answer whether there are limits to human populations.
Vandermeer’s Study
The research of Vandermeer (2010) should be seen as a mathematical study of the patterns and regularities of exponential population growth, along with the conditions for limiting such growth. The author initially discusses the meaning of such a study, noting that it involves modeling and predicting population growth using exponential equations. In this section, the author elaborates at length on the mathematical and applied meanings of the exponential equation, providing a relief of material for the uninformed reader. Apart from the example of bacterial growth, the author also cites the growth of lilies in a pond and of wheat grains to ease understanding of the material. The author raises the question of whether unlimited growth can be a problem and points out that there are threshold factors that limit population growth.
Vandermeer (2010) then updates the previously derived exponential equations by introducing an intraspecific competition factor that reduces population density: as population density increases, the population growth rate decreases. The differential equation for population growth is quadratic, meaning the growth rate is equalized with increasing population density. As a result, the author develops a logistic equation that accounts for population carrying capacity constraints, which is the main conclusion of this study. Such an equation enables accurate modeling of population growth while accounting for constraints imposed by population density.
References
Snider, S. B. & Brimlow, J. N. (2013). An introduction to population growth. Nature Education Knowledge, 4(4), 1-3.
Vandermeer, J. (2010). How populations grow: The exponential and logistic equations. Nature Education Knowledge, 3(10), 1-15.