BIOL 372 Lecture Notes - Lecture 3: Desert Iguana, Co-Phenotrope, Parasitemia
Document Summary
Lecture 3: disease manifestations: signs and symptoms {revisions are in green font} Goals of lecture: to discuss the evolutionary functions of disease manifestations and the implications of this knowledge for assessing the consequences of symptomatic treatment. Disease manifestations: perceptible changes in the host that indicate disease. Symptoms: subjective manifestations of disease (e. g. , the feverishness a person feels when sick), Signs: objective manifestations of disease (e. g. , the elevated body temperature) Evolutionary categories of manifestations: defenses, manipulations, & side effects. Defense a manifestation (i. e. , a symptom or sign) of a disease that increases the evolutionary fitness of the individual expressing the manifestation. Exploitation (=manipulation) a manifestation of a disease that increases the evolutionary fitness of the agent that causes the manifestation. Side effect a manifestation of a disease that benefits neither the host nor the agent of disease. For nonliving, noninfectious ailments, evolutionary implications are easier to assess because. -long evolutionary histories should have weeded out responses that are damaging side effects.
