Question 2: Symbiosis Symbiosis is another type of two-species interaction. It literally means living together, and refers to pairs of species that live in close physical proximity with the other species for a major part of their life cycles. Some examples of symbiosis: You and the microorganisms that live in your intestines; bark beetles burrowing in pine tree trunks; Monarch butterfly caterpillars and milkweed plants; and algae living in coral tissues. Can you think of any symbiotic interactions that are commensal or parasitic