Evolution Changes induced by Humans

Human Activities and Global Climate Change

Human activities have negatively impacted on the environment. As a results of the activities, the planet has experienced global climate change that has ultimately led to an evolution of several species (Helen 2014, p 1). Global climate change is poised to become the serial murderer of the many plant and animal species. For instance, with rapid temperature changes within the whole world, ecosystems are thrown into a series of problems like loss of habitat that has pushed for extinction. Some scientists have argued that Earth is on the verge of another extinction event. The priority here is that if plant species and animals can adapt quickly to cope with the climate change and human-induced environmental changes (Sarah & Ryan, 2016). People think that evolution is a slow process. However, it is the opposite. If the selection pressures tend to be strong, evolution happens over decades. Human-induced changes in the evolution of other species are majorly caused by unnatural selection through harvest of wild animals.

Harvesting and Evolution

Humans have ventured to a harvest of phenotypically desired characteristics of wild animals thus imposing selection that reduces the frequencies of such desirable phenotypes. Fishing and hunting, on the other hand, contrast agricultural practices aimed at phenotypically breeding the desirable characteristics with a specific goal of increasing the frequency of desirable phenotypes. While observing evolution induced by humans, closer attention is paid potential effects of harvesting on the genetics and the sustainability of the existing populations. Harvesting also considers the mating system is hence modifying the selection in a manner that affects the recruitment process. Its likely that undesirable qualities are due to the selection that sidelines desirable phenotypes and therefore results in unnatural selection. Evolution of species as a result of human harvesting may increase the time needed for overharvested populations to recover. The long time is since the process normally creates strong selection differentials.

Human Harvesting and Selective Removal

Humans have been exploiting wild animals for food and clothing and also in making tools. Therefore human harvest of these animals is planned. A man practices the selective removal of certain genetics to causes changes in the harvested populations of wild animals (Allexis et al., 2017). The animals are selected by body size, morphology and regarding behavior as others are removed from the populations. Selective removal of wild animals on the above-stated basis brings about genetic changes in the populations being harvested. Selected harvesting of various species causes genetic changes to the species if the selection exhibits partial genetic basis.

Harvesting and Agriculture

In the field of Agriculture, harvesting has been practiced for thousands of years in breeding the most productive animals (Fred & Jeffrey, 2009). All the above is done with the goal of increasing the desirable phenotypes of the bred population. Aquaculture has adopted the same objectives despite its short existence. However, the practice as well involves exploitation of the wild animals. When the animals with the desirable characteristics have been harvested, they leave behind the less desirable to continue reproduction and contribute genes of future generations.

Types of Natural Selection and Human-induced Evolution

According to Charles Darwin, there are three types of natural selection that are considered human-induced evolution. The three types include; unconscious, methodological and natural. He discussed how the removal of desirable animals through hunting reduces their frequency of animals with desirable characteristics. Harvest affects the sexual selection of different species because it has the intention of removing individuals with specific characteristics from breeding with the other population. Sexual selection, therefore, acts in the context of natural selection.

Technological Impact and Human-Induced Evolution

Accelerated evolutionary changes are easy to understand since they are derived from the strong natural selection that is exerted by human force (Jay 2009, p 1). The human forces take the form of technology. Technological impacts have increased evidently over the past few years signifying that the humans might be the dominant evolutionary force playing the role causing evolution to other species (Stephen, 2001). The human-induced changes can be measured economically and in some cases manifest itself regarding pest and disease outbreaks. The attempts of reducing these changes are uncoordinated.

Human Activities and Evolution in Pest and Disease Resistance

As a result of human activities, several species have developed resistance that is reported as a result of evolution. For example, during the discovery of DDT as insect killer was reported with the evolution of resistance in houseflies. The resistance of other insects to DDT, for instance, mosquitoes led to global failure in the eradication of malaria. By 1990, its estimated that more than 500 species had developed resistance to more than one insecticide. Insects often show evolution and resistance after an exposure lasting more than a decade. Thus, many insects show resistance to pesticides hence difficulty in controlling. Similar resistance has also been shown in trajectory weeds which often evolve between 10 to 25 years.

Human Activities and Evolution in Bacterial Diseases

As a result of human activities, bacterial diseases have shown evolution and devastating resistance to the antibiotics in use. The resistance takes places at low levels of natural population and has become common over the past few years. Evolutions in the face of both antibacterial and antiviral drugs are both rapid processes and can take as short as two weeks. Therefore rapid evolution as a result of human activities is not only restricted to pest and diseases but also the other species.

References

Allexis P. Sullivan, Douglas B. Bird & George H. Perry. (2017). Human behavior as a long-term ecological driver on nonhuman evolution. [online]. (updated 2017). Available at: http://www.nature.com/articles/s41559-016-0065 [Accessed Oct. 8, 2017]

Brad Balukiajn. (2014). Why Doesn’t Everyone Believe Humans Are Causing Climate Change? [online] (updated 2004). Available at http://www.pbs.org/wgbh/nova/next/earth/climate-change-acceptance [Accessed Oct. 8, 2017]

Fred W. Allendorf & Jeffrey J. Hard (2009). In the Light of Evolution: Centuries of Darwin. [online] (updated 2009). Available at https://www.ncbi.nlm.nih.gov/books/NBK219730/ [Accessed Oct. 8, 2017]

Helen Thompson (2014). The Species That Are Evolving Due To the Changing Climate

Jay T. Stock (2008). Are all humans still evolving? [online](updated 2008). Available at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3327538/ [Accessed Oct. 8, 2017]

Jess Zimmerman. (2014). How Humans are Forcing Other Species to Evolve. [online] (updated 2014). Available at http://grist.org/article/2011-05-05-how-humans-are-forcing-other-species-to-evolve/ [Accessed Oct. 8, 2017]

Sarah E. Diamond and Ryan A. Martin. (2016). The interplay between Plasticity and Evolution in response to human-induced environmental change. [online](updated 2016). Available at https://f1000research.com/articles/5-2835/v1 [Accessed Oct. 8, 2017]

Stephen R. Palumbi (2001). Humans as the World’s Greatest Evolutionary Force. [online](updated 2001). Available at http://palumbi.stanford.edu/manuscripts/evolution.pdf [Accessed Oct. 8, 2017]