BISC 313 Lecture Notes - Lecture 10: Ectosymbiosis, Spanish Moss, Commensalism
Document Summary
Many relationships could be considered ectosymbiotic, many parasitic relationship and some mutualistic relationships fall under endosymbiosis, organisms living within another organism. They gain habitat space but do not harm the hermit crab. Is (ecto)symbiotic: commensalism, obligate (for the clam) Ex: spanish moss- an epiphyte that grows on many different tree species. Absorbs water and nutrients from the air and rainfall. Rarely kills the tree it grows on. facultative commensalism: symbiotic. Ex: barnacles living on a crab or whale: facultative commensalism, symbiosis, ex: tomato hornworms are the larvae of the five spotted hawk moth that feed on tomatoes, peppers, tobacco, and potatoes. The larvae commonly can completely defoliate plants by not often kill them outright: facultative herbivory. For a mutualism to persist: cost > benefits. The partners in a mutualism are not altrustic. Altruism: a social interaction that enhances the fitness of an unrelated recipient while reducing the fitness of the donor.