Mutualism

Question 1

Define: mutualism

Answer 1

= both species benefit from relationship- but is selfish and not desire to be helpful so is prone to exploitation and cheating (NOT GOOD TO CHEAT)

Question 2

What are the types of mutualism?

Answer 2

faculative = only engaged opportunistically

obligate = one or both partners dependent on the other

Combinations of the 2 are possible- so mutualists can be specialised or generalised

Question 3

what is example of facultative and generalised mutualist

Answer 3

honeyguide (bird) and humans

Question 4

Describe an example of an obligate and specialised mutualism?

Answer 4

African tree- has fruits size of human head that can only opened by elephants
- seeds need to pass through elephant gut in order to germinate

= elephants only dispersal agent for seeds- elephants only facultative as they can eat other things

Question 5

Describe an example of facultative and generalised mutualism

Answer 5

Interaction between ants and sap-sucking insects
- insects produce honeydew as waste product which the ants collect
- in return the ants protect bugs from predators

both benefit but can persist without the other

Question 6

What are the 2 main advantages of mutualistic interactions? + examples

Answer 6

• access scare resources- one species can trade its waste or surplus product for a resource it lacks
  e.g. green salamander- algal species penetrates eggs and enters during development
  algae benefits from protection and direct source of CO2
  salamander gains O2 released by algae during photosynthesis
• Protection
  e.g. red ridged crab very vulnerable to predators and hides in ivory bush coral- it prevents the coral from being outcompeted by algae as it grazes on it and in return coral produces nutritious mucus for crabs

Question 7

What is a 2 common feature of mutualism?

Answer 7

mutualism can turn into other interactions like commensalism or even parasitism

specialism is usually one sided- 2 way specialism incredibly rare as it would result in both species being vulnerable to extinction

Question 8

What risk is there to mutualistic interactions?

Answer 8

Exploitation and cheating

Question 9

Describe an example of how mutualisms are policed

Answer 9

Yucca plants are pollinated by moths which lay eggs in ovaries
The moths want seed to develop for food for their caterpillars
Plant regulates mutualism by aborting flowers that have 6+ eggs so moths have to obey this rule in order to not lose their eggs

Question 10

Describe an example of specialised mutualists