Chapter 15: Mutualism

mutualism

interactions between individuals of different species that benefit both partners

obligate mutualism

species cannot survive if the species do not interact

facultative mutualism

they can live without each other but they do better when they interact

mutualism persists if

fitness of successful mutualists > fitness of unsuccessful mutualists and non mutualists

combined fitness of mutualists > fitness of non mutualists > fitness ofp

plant mutualists

pollination, nutrient absorption, seed dispersal

mycorrhizal associations

mutualistic association between plant roots and specialized fungi

plants receive benefits such as making nutrients available to plants

improves plant ability to extract water

more often then not facultative mutualism

ants and swollen acacias

ants aggressively defend home tree from herbivores and acacia provides year round food source (leaves and nectarines and beltian bodies)

obligate mutualism

coral mutualism

corals depend on mutualisms with algae and animals

reefs support high levels of biodiversity

coral and zooxanthellae

coral receive organic compounds from zooxanthellae and control compound release

zooxanthellae live in tissue of corals, receive nutrients from coral through ammonium waste, coral can induce zooxanthellae to release more organic compound for them

coral and crustaceans

facultative

xanthidae crabs stimulate production in coral

crustaceans provide coral with protection from predators