Tilman later employed Monod kinetics for examining the competition between two different types of algal populations, as a function of limiting resource ratios 7. Monod’s equations were derived from extrapolations of data obtained from bacterial grown in batch cultures, but he proposed the method of continuous growth which was later used to verify many of his predictions 6. He then mathematically incorporated this relationship into the equation for exponential bacterial growth, thereby providing a model for the relationship between growth rate and the concentration of a limiting nutrient, an equation similar to the Michaelis-Menton representation of enzyme kinetics 5, 6. In defined medium, in which all but one isolated nutrient was provided in excess, he demonstrated that “total growth”, or bacterial growth yield, is linearly dependent on the initial concentration of the limiting nutrient 5. Jacques Monod, a pioneer in the study of bacterial growth kinetics, first demonstrated the relationship between limiting nutrient concentrations and bacterial growth. Nutritional resources are a focal point of microbial competition. The potential pool of microbial competitors is therefore vast, and a wide range of mechanisms can be responsible for the emergence and radiation of dominant microbial populations. Members of the rare biosphere that are amplified under favorable conditions to which they are pre-adapted can give rise to discrete, abundant populations. These approaches and others have begun to reveal that underlying the numerically dominant microbial populations is a highly diverse, low-abundance population (described as the rare biosphere, see 3 ). Tremendous microbial diversity has been revealed by new molecular methodologies such as metagenomic sequencing and deep microbial tag sequencing 3, 4. Vast numbers of microbes are present in all but the most rarified environments. Similarly, most microorganisms face a constant battle for resources. Thus, the habitat of Chthamalus was limited to areas where it could escape from competition with Balanus, an example of competitive exclusion. However, Balanus could not grow further up the rocks, due to desiccation sensitivity. If he experimentally removed the Balanus barnacles from the lower areas, Chthamalus could grow there, but upon reintroduction of Balanus, Chthamalus would eventually be crowded out by the more competitive Balanus. He found that in intertidal zones in Scotland, Balanus barnacles were always found closest to the shore, while Chthamalus barnacles grew further up the rocks. Connell’s barnacles provide a classic example 2.
In animals and plants, there are a large number of well studied examples of populations which are held in balance, or driven to transition, by competitive forces. This leads to natural selection, which provides the driving force for innovation and diversification between competing organisms 1. The battle for resources through which organisms survive and pass on genes to the next generation can often be fierce and unforgiving. The high level of competition in human society in many ways mirrors the comparatively ancient and complex interactions observed at virtually every level in the natural world. In capitalist societies, competition is thought to continually hone the attributes of competing entities, improving their efficiency and defining their activities and structure. Competition is a fact of modern life, with individuals and institutions vying to gain advantage in terms of finances, material resources, and status. Examples of true charity and altruism in human societies are highly lauded, and rightfully so, but are far from the norm.
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