Topic 9: Populations and Metapopulations Flashcards
What is a plant or animal produced from sexual reproduction from a zygote called?
genet
What are the modules produced through asexual means?
ramets
What does the distribution of a population represent?
represents the presence and absence of individuals.
What is the distribution of population influenced by?
environmental conditions
What is meant by environmental heterogeneity? and what does it cause?
environmental heterogeneity means mixing of “conditions”. basically differences in conditions (topography, soil etc)
Environmental heterogeneity causes most populations to be divided into subpopulations.
What does the abundance of a population refer to?
abundance of a population refers to the population size or the number of individuals.
What is population density?
the number of individuals per unit area. can be estimated in crude form by way of a gird.
What is the problem with calculation population density?
problem is that individuals tend to not be equally numerous everywhere and density is often not uniform.
What is spatial distribution? What kind of interaction is present in random, uniform or clumped distribution? Which is the most common?
spatial distribution refers to the spatial position of one individual to another.
random - no interaction happening at all. resources are randomly scattered across the range.
uniform - comes with negative association (ie: competition)
clumped - comes with positive association with other (can benefit from one another) most common interaction.
What is age structure?
age structure is the number or proportion of individuals in different age classes.
In what instance is there no age structure?
in organisms that only live for a single season.
Populations can be divided into 3 ecologically important age classes/stages. What are they?
pre-reproductive, reproductive, and post-reproductive.
What is a cohort?
a small subpopulation sample of a larger population to make inferences about the whole.
What is a metapopulation?
a metapopulation is a group of local subpopulations within a larger area or region.
How are subpopulations connected?
subpopulations are connected through movement of individuals and interact by dispersal and gene flow.
What is colonization?
colonization is the movement of individuals (via dispersal) from occupied patches to unoccupied patches and forms new subpopulations.
The rate of colonization into suitable populations depends on two factors. What are these factors?
- the proportion of empty patches
- proportion of patches providing colonizers
What is extinction?
extinction is the complete loss of a subpopulation from an occupied patch.
What does it mean if:
colonization rate = extinction rate ?
colonization rate > extinction rate ?
colonization rate < extinction rate ?
- the number of patches occupied remains static at equilibrium.
- more patches will be occupied until the median (~50% of patches are occupied) is reached.
- will be brought back the median.
What is a synchronized event?
synchronized event acts on EVERY subpopulation within a metapopulation at the same time and may pose an extinction risk for the entire metapopulation
