Micro-evolution

Student Name:
Professor:
Course:
Date:
MICRO-EVOLUTION
Micro-evolution is the evolution that takes place below the level of species, for instance, the change of gene frequency of organisms’ population or the procedures on which new species are developed (Endler). Changes in micro-evolution may be due to one of the following processes; genetic flow, genetic drift, mutation as well as natural selection (Endler). Changes in this type of evolution are observed over short durations of time (Endler). Scientists have tried to find laboratory evidence of micro-evolution. In their findings, organisms with certain markings that permits them to better blend with their particular surrounding, as well as presumably avoid being visualized by the predators. In this experiment, when predators were removed from the surrounding, the markings of the organisms stood out more in their surrounding likely to attract mates, in case of sexual selection (Endler).
Similarly, evidence of micro-evolution has been demonstrated in the field. For instance, since sparrows’ introduction in North America in 1852, the development of different traits of the sparrows in different places has been observed (Johnston & Robert, 376). They have evolved differently exhibiting different traits such as larger body-size that aid the sparrows in surviving in low-temperature areas. The small-bodied sparrows survive in warm temperature places (Johnston & Robert, 378). Moreover, the sparrows in the South also developed lighter color of the marks on the feathers (Johnston & Robert, 388).

Additionally, micro-evolution is evidenced by the case of antibiotic resistance (Morschhäuser, 701). In each generation of bacteria, new mutations and combinations of genes are generated. Natural selection favors gene versions of organisms that confer resistance to the exposed antibiotic (Morschhäuser, 702). Over the courses of multiple generations of bacteria, the bacteria adapt to human defenses hence evolving right out from human attempts to get rid of the bacteria from themselves (Morschhäuser, 704).
References:
Endler, John A. Natural selection in the wild. No. 21. Princeton University Press, 1986.
Morschhäuser, Joachim, et al. “Evolution of microbial pathogens.” Philosophical Transactions of the Royal Society of London B: Biological Sciences 355.1397 (2000): 695-704.
Johnston, Richard F., and Robert K. Selander. “Evolution in the house sparrow. III. Variation in size and sexual dimorphism in Europe and North and South America.” The American Naturalist 107.955 (1973): 373-390.