Symbiotic Relationships February 17th 2016

Shape of the Day 10 – 15 minutes – Run through lecture at breakneck speed Rest of Block – Organism Research in Library

Learning Objectives Define symbiosis Define and give examples of parasitism, commensalism and mutualism

Symbiosis When two organisms share a close relationship, where at least one benefits

Parasitism Where one party benefits and the other suffers + / -

Parasitism Where one party benefits and the other suffers + / -

Parasitism Parasites usually don’t kill their hosts, why not? Because from an evolutionary standpoint, if the hose dies, the parasites die as well.

Parasitism Unless the parasites have already reproduced.

Commensalism When one party benefits and the other is unaffected + / 0

Mutualism When both parties benefit + / +