Facilitation and Mutualism Flashcards
What is the difference in the definition of facilitation and mutualism?
Facilitation is a one-sided positive interaction where one species benefits another without reciprocity. Mutualism is a co-evolved relationship where both species benefit and the benefits are reciprocated.
In what ways can one plant species facilitate another plant species?
Providing refuge from physical stress
Reducing predation
Improving resource availability (e.g., water, nutrients) through litter fall or hydraulic lift
In what type of environment is a closed canopy patch better for seedling establishment?
In more arid environments, as it moderates temperature and moisture stress.
What is a nurse plant?
Long-lived woody shrubs that create a favorable micro-environment under their canopies.
Does a nurse-protégé relationship necessarily stay the same over the lifetime of both species?
No, the protégé may start competing with the nurse plant for resources, leading to a more exploitative relationship.
What is hydraulic lift and how could it support seedling establishment?
Hydraulic lift is the process where deep-rooted plants move water from deeper soil layers to shallower soil layers, supporting seedling establishment by making more water available.
Did hydraulic lift significantly support seedling growth in the experiment presented in class?
No, it did not significantly support seedling growth.
In what environments do we see cushion plants and what is their effect on plant diversity?
Cushion plants are found in harsh alpine environments and increase species richness by providing a safer microhabitat for other species.
What does the stress-gradient hypothesis predict?
In harsh environments, facilitative interactions between plants are more common; as environmental stress decreases, competitive interactions become more dominant.
What are the two main categories used to classify mutualistic relationships?
Obligate mutualism
Facultative mutualism
What is the definition of symbiosis?
Symbiosis is a close physical association between two species, which may not necessarily be mutualistic.
Give an example of mutualistic symbiosis.
Rhizobium-legume mutualism, where both species benefit.
Give an example of parasitic symbiosis.
Mistletoe and its host tree, where mistletoe benefits while harming the tree.
Which is the most prevalent mutualism flowering plants engage in?
Plant-pollinator mutualism.
What do plants provide to pollinators in a mutualistic relationship?
Nectar or pollen (food).
What do pollinators provide to plants in a mutualistic relationship?
Transfer of pollen, facilitating plant reproduction.
What is a mutualism involving plants that is also a symbiosis?
Rhizobium-legume mutualism.
What is the definition of cheating in a mutualistic relationship?
One partner benefits without providing the reciprocal benefit.
Can any mutualist cheat? Give an example.
Yes, a cheating yucca moth lays more eggs than the yucca plant can handle, leading to less seed production.
In general, how is cheating controlled to assure the persistence of mutualism?
Through mechanisms that penalize cheaters and promote cooperation.
How does a legume control cheating rhizobium strains?
By limiting oxygen supply to nodules containing cheater strains.
How does a yucca control cheating yucca moth genotypes?
By aborting flowers that have too many eggs laid in them.
How does a yucca plant control cheating by the bogus yucca moth?
By aborting flowers that are infected with eggs from the bogus yucca moth.
What is Batesian mimicry? Give a plant example.
Non-toxic or harmless species mimics the appearance of a harmful or toxic species. Example: Some plants have flowers that mimic the appearance of milkweed.
