Trypanosomes coevolved with humans through a variety of mechanisms that left lasting effects on both organisms. These parasites generate two main human diseases: Chagas disease, caused by Trypanosoma cruzi, and African sleeping sickness, caused by Trypanosoma brucei. These two trypanosomes diverged early in humans, and therefore, evolved very differently from each other, each leaving its own impact on its host (Stevens and Gibson 1998). Human and non-human immune systems have developed many defenses against these parasites. Through an array of mechanisms: human migration (Stevens and Gibson 1998), industrialization (Gakuppo et al. 2009), and improvements in health care (Matovu, Seebeck, Enyaru, and Kaminsky 2001) these environmental pressures …show more content…
2009), instead the human immune system evolved another way to combat trypanosome infection. The human MHC complex allows the presentation of a foreign antigen to the immune system. For a parasite to have an impact on the evolution of the MHC complex it must coevolution with its host for an extensive period of time (Klein 1991). Certain trypanosomes have uniquely impacted the human MHC complex in a way few other parasites can claim. Trypanosomes possess flagella, meaning they are among the oldest eukaryotic organisms (Teixeira et al. 2009). The human MHC complex is polymorphic, meaning it can have many variants. The clonal evolution of parasites, specifically trypanosomes, pressured the human immune system to have a polymorphic MHC complex (Klein …show more content…
cattle bread in Europe. Researchers found that cattle bread in Africa had a significant difference in resistance to ticks and trypanosomes (Mattioli, Pandey, Murray and Fitzpatrick 2000). This correlation displays that hosts with a long relationship with a parasite evolve slightly different defense mechanisms specific to that parasite.
Researchers sought to describe the relationship between host, parasite, and food quality. In bumble bees, a high concentration of sugar in water (high food quality) lead to an increased survival rate with a parasite (Sadd 2011). This demonstrates that the environment shapes host-parasite interactions. This could link climate change and human disease in regards to trypanosomes. This adds evidence for the Red Queen Hypothesis, which states, organisms must evolve to survive (Sadd