Chapter 12 Flashcards
The process where one species gives rise to several others that exploit different features of the environment is known as
adaptive radiation
As the population of a predator increases, the…
population of the prey species decreases
When the trunk or limb of a tree provides the substrate on which an epiphytic orchid grows, the arrangement benefits the orchid (which gets nutrients from the air and moisture from aerial roots) while the tree is unaffected. This relationship is referred to as
Commensalism
In most plant-pollinator interactions, plant species are pollinated by
multiple animal species and each animal species pollinates multiple plant species
Adaptive radiation is often the result of
resource competition
A remora feeds on the scraps that escape from a shark’s mouth while feeding. It has no clear positive or negative impact on the shark. This is an example of…
commensalism
A food web is a better representation of a community than a food chain because most interactions among organisms…
are diffuse across a range of contexts
An ecological niche is typically ___ dimension(s)
an unspecificed number of
A realized niche can be larger than a fundamental niche….
when a commensal species expands another’s niche space
As two competing species approach their respective carrying capacities, the growth rate of the other species…
slows down
What are the 3 types of possible interactions?
Positive (+)
Detrimental (-)
Neutral (0)
Define neutral interaction
Neither species affects the other (0 0)
Define mutualism
Both species benefit from each other (+ +)
Define commensalism
Benefit for one, other is unaffected (+ 0)
Define amensalism
Detrimental to one, other is unaffected (- 0)
Define predation
One species eats, other dies (+ -)
Define parasitism
One species feeds on another, reducing the host fitness but not killing it (+ -)
Define parasatoidism
One species uses another for reproduction, and its larvae feed on the host and eventually kill it (+ -)
Define agent of mortality
Something that impacts a species deathrate. when a predator kills prey for an example
As number of predators (Npredator) increases, what happens to prey population?
Number of prey captured and killed increases. Deathrate of prey increases (dprey).
Positive linear relationship.
What is the equation for interspecific competition? (2 different species)
dN1 / dt = r1N1 (1-((N1+N2)/K1))
What does the presense of a second species do to the carrying capacity of the 1st species?
If both species use same resources, they share the same carrying capacity. This leads to a reduction of the potential individuals of species 1.
What is the equation using the competition coefficient alpha? What does alpha represent?
Alpha represents the impact of species 2 on species 1.
dN1 / dt = r1N1 (1-((N1+αN2)/K1))
What is the equation using the competition coefficient beta? What does beta represent?
Beta represents the impact of species 1 on species 2.
dN2 / dt = r2N2 (1-((N2+βN1)/K2))
Define coevolution
Process in which 2 species undergo reciprocal evolutionary change through natural selection.
What are the 2 main reasons for coevolution?
- Counter-adaptive changes attempting to thwart other species
- Reinforce the effect of adaptive change in mutually beneficial interactions
What can coevolution lead to?
Divergence of phenotypes due to a desire of wanting to reduce competition. Can also lead to mimicry between species.
Define ecological niche
Species is the range of physical and chemical conditions under which a species is able to survive and reproduce
Define competitive exclusion principle
2 species can’t coexist if they occupy exactly the same niche.
Define multidimensional hypervolume
Each dimension is a variable that relates to a specific resource. There are n# of dimensions that an organism lives in.
Define fundamental niche
Environmental conditions in which a species can survive and reproduce
Define realized niche
Portion of the fundamental niche that a species actually uses as a result of interactions with other species
