Evolution is a dynamic, interactive process that occurs constantly in nature, however, in a sense, humans have had disproportionate influence on evolution of other species thanks to the development of technology that allows us to achieve effects that animals in nature could not have accomplished. I think this is a very interesting article because we have read about how human interactions with the environment have changed pathogen transmission patterns in class, and this article provides more evidence that we might not be aware of.
12,000 years ago, domestication of wolves into dogs. Humans have domesticated all kinds of animals. Now days, the industrial, massive way humans fish is causing marine species to evolve to reproduce at younger ages and smaller sizes in order to keep passing on their genes. More specifically, cod, which have been overfished for decades off New England and the Canadian Maritime Provinces, have begun reproducing at younger ages and smaller sizes. Other species that have been observed to shower similar changes are bighorn sheep, caribou and ginseng plants. The shift in reproductive pattern improves the chances of reproducing before being killed, which gives those animals a short-term survival advantage. But it is harmful for the them in the long run, according to Paul Paquet, an environmental scientist at the University of Calgary, because the smaller, younger offsprings are not as strong and healthy as the older and bigger ones. Consequently, they are less likely to survive on their own. He refers to this phenomenon as “forced evolution”. As a result, Maine has passed legislation to protect lobsters and other common fish species from being hunted at a young age.
In addition, climate and landscape change have altered animal and plantation’s living environment beyond our estimation. For example, the development of highways and deforestation have physically limited the habitats of many wild animals and decreased their offsping’s diversity, which is detrimental for them in the long run. Furthermore, as a result of climate change, plantations shift their timing of bloom or move to a higher altitude in order to survive and reproduce.
The introduction of apples to North America in the 17th century led some fruit flies that had specialized on hawthorn fruit to branch out to apples instead. By the mid-1800s, the branched out flies have completely separated to form its own species. Further down the stream, that has encouraged modification of parasitic wasps that feed on those flies.
When we read about a specific study on a specific pathogen, the human impact on nature does not seem to be too detrimental. However, when we look at the bigger picture that include all aspects of ecosystem, humans have greatly altered the way animals and plants survive and reproduce in nature.
Dean, C. (2009, February 10). Seeing the Risks of Humanity’s Hand in Species Evolution. The New York Times. Retrieved from http://www.nytimes.com/2009/02/10/science/10humans.html