•In your summary reflect on one aspect that you find important to your interests (eg a new model for fat metabolism, or a unique system for conservation biology etc):
My interest in this paper: parasite infection setting conditions for a possible speciation event
Long distance migratory species like monarch butterflies (Danaus plexippus) are an interesting subject of study, because if they are exposed to selective pressures like parasitic protozoans such as Ophryocystis elektroscirrha during their migratory journeys, there are chances of fragmenting the population and setting the conditions for an speciation event to occur.
Migration is triggered by cues of habitat deterioration such as the photoperiod that instill an animal to travel to another location where resources and living conditions will be more favorable. It can also have indirect benefits, like reducing the predominance of parasites among a population by removing the infected individuals, a phenomenon known as "migratory culling". Such is the case for long-distance migratory monarch butterflies (Danaus plexippus) and parasitic protozoans like Ophryocystis elektroscirrha in North America.
It is known that parasitic infection rates are higher southwards in eastern North America, supporting the evidence that infected monarchs are slower and have less endurance, thus performing poorly in migration. The objective of this study was to determine the effect of parasite infection in the flight performance of monarchs migrating towards their wintering grounds in Mexico. The researchers hypothesized that infected individuals would travel shorter distances, and that among infected individuals shorter distances are correlated with higher parasite loads.