The Columbian Exchange refers to a historical period of exchange of animals, plants, diseases, and technology between the Old World (Europe, Asia, and Africa) and the New World (the Americas). It is considered one of the most significant events in cultural history because it affected nearly all societies by bringing deadly diseases and expanding the variety of new crops and livestock. Today, rats can be found anywhere in the world, but they are native to Asia (commonly found in large numbers in China, Japan and India) and eventually arrived in Europe via established trade routes, passing through Turkestan and a region around the Black Sea. Europeans initially disliked the presence of rats because they helped spread the bubonic plague, which killed a third of Western Europe's population. Although fleas were the main reason for the spread of bubonic plague, they fed on the blood of infected rats. Other than that, rats don't seem to cause much damage to Europe. While some people view rats as affectionate and intelligent rodents, others may consider them dirty and unattractive. During the period between 1450 and 1750, rats served as pests by spreading and eating all the settlers' food, competing with the small native animals of the New World, and today the people of the United States have developed methods to avoid the presence of rats using methods such as poison or traps. However, although rats had a negative impact on the New World by bringing diseases, diseases have always been prevalent even before the spread of rats throughout the world. Rats were transported from the Old World to the New World during the Columbian exchange across the Atlantic. waters. Although Europe......middle of paper......with unpleasant things, such as disease and dirt. The black and brown rats are the most common variations of rats found today, but they have originated, through trade, in almost all parts of the world today. Works Cited http://www.gilderlehrman.org/history-by-era/american-indians/essays/columbian-exchange http://public.gettysburg.edu/~tshannon/hist106web/site19/ http://www. crf-usa.org/bill-of-rights-in-action/bria-25-1-the-columbian-exchange http://www.jstor.org/discover/10.2307/3868189?uid=3739832&uid=2&uid=4&uid=3739256&sid=21102935431757 http://books.google.com/books?id=7yClMF7IQt8C&pg= PA97&lpg=PA97&dq=how+rats+were+involved+in+the+Colombian+exchange&source=bl&ots=WY P-eGyHWv&sig=bPGAqL7e-F8cOrV8zX81G2yJ1U0&hl=en&sa=X&ei=HFuIUpbmNanPsASl74DgAQ&ved=0CDQQ 6AEwAQ#v=a page&q=how%20were%20rats%20involved% 20in%20the%20Colombian%20exchange&f=false