During evolution, many parasites have developed sophisticated strategies to improve their chances of survival.
An interesting case is that of the protozoan responsible for toxoplasmosis : Toxoplasma gondii . This parasite, in fact, is able to make rodents of easy prey for the cat, which represents the definitive host of the pathogen.
Unlike healthy mice - which avoid areas frequented by cats (recognized by the smell of their predator's urine) - infected rodents behave as if they were attracted to them. In fact, during the Toxoplasma gondii infection, brain changes occur that modify the natural behavior of mice .
Thus Toxoplasma gondii increases the probability of completing its biological cycle in the definitive host.
