Fundamental niche vs Realized niche
The range of abiotic conditions under which species can persist vs the abiotic and biotic conditions where it does persist.
How does the realized niche determine the geographic range of a species?
The abiotic and biotic conditions where a species persists makes up the area that a species inhabits or its geographical range
Give 2 reasons why a species might be absent from a location that an ecological niche model predicted to be suitable
- Presence of predators
- Presence of a parasite/pathogen
- Competition
Endemic vs Cosmopolitan species
A single, often isolated, range vs large geographic ranges that can span several continents
Of endemic and cosmopolitan species, which are more vulnerable to habitat change/loss?
Endemic species
The dispersion pattern characterized by individuals that are aggregated.
Clustered
The dispersion pattern characterized by each individual maintaining a minimum distance between neighbours.
Evenly spaced
The dispersion pattern characterized by each individual’s position being independent of the location of other individuals.
Random
What might cause Clustered dispersion patterns?
- Living in social groups
- Proximity to clustered resources
- Parent/offspring proximity (especially in plants like Aspen)
What might cause Evenly spaced dispersion patterns?
- Territories
- Competition
- Chemicals (plants, inhibits growth near them)
Dispersal vs migration
Permanent vs Temporary
What is area/volume based sampling? What is this method best used to count?
When a quadrat is set up and the amount of individuals in each quadrant in counted. Best for immobile species.
What is line-transect sampling? What is this method best used to count?
When researchers count the number if individuals along a line. Best for immobile species or species that do not distribute easily (slow or restricted to an area).
What is mark-recapture? What is this method best used to count?
An amount of individuals are captured, marked and released. A second survey is done at a later date and the number of marked and unmarked individuals are noted and compared. Best for highly mobile species.
The formula to calculate mark-recapture data is as follows:
M/N=R/C
What do the variables represent?
M= # marked
N= Population size
R= # of marked individuals
that were recaptured
C= Total # captured in second survey
Rearrange the mark-recapture formula to solve for population size
N=(M/C)/R
On a graph, the relationship between individual body size and population density is best described as...
a) linear
b) exponential
b) exponential
What is dispersal limitation? What are some examples?
The absence of a population from suitable habitat because of barriers to dispersal.
- Water bodies
- Inhospitable habitats (species specific)
- Roads
- Mountains
What does the basic metapopulation model describe? What is it best used for?
A scenario in which there are patches of suitable habitat embedded within a matrix of unsuitable habitat.
What nuance the source-sink metapopulation model add to the basic model?
When it is necessary to also consider the quality of patches.
What makes the landscape metapopulation model so complicated? Why might we not use it if it theoretically provides the most nuanced results?
The consideration of quality differences in suitable patches AND in the surrounding matrix.
The quality of the matrix is sometimes not necessary to consider (e.g., terrestrial species on an isolated island or fish in an enclosed pond)
What is the basic metapopulation model best used for?
Emphasizing how colonization and extinction events can affect the proportion of total suitable habitats that are occupied.