Topic 9: Populations and Metapopulations

Question 1

What is a plant or animal produced from sexual reproduction from a zygote called?

Answer 1

genet

Question 2

What are the modules produced through asexual means?

Answer 2

ramets

Question 3

What does the distribution of a population represent?

Answer 3

represents the presence and absence of individuals.

Question 4

What is the distribution of population influenced by?

Answer 4

environmental conditions

Question 5

What is meant by environmental heterogeneity? and what does it cause?

Answer 5

environmental heterogeneity means mixing of “conditions”. basically differences in conditions (topography, soil etc)

Environmental heterogeneity causes most populations to be divided into subpopulations.

Question 6

What does the abundance of a population refer to?

Answer 6

abundance of a population refers to the population size or the number of individuals.

Question 7

What is population density?

Answer 7

the number of individuals per unit area. can be estimated in crude form by way of a gird.

Question 8

What is the problem with calculation population density?

Answer 8

problem is that individuals tend to not be equally numerous everywhere and density is often not uniform.

Question 9

What is spatial distribution? What kind of interaction is present in random, uniform or clumped distribution? Which is the most common?

Answer 9

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.

Question 10

What is age structure?

Answer 10

age structure is the number or proportion of individuals in different age classes.

Question 11

In what instance is there no age structure?

Answer 11

in organisms that only live for a single season.

Question 12

Populations can be divided into 3 ecologically important age classes/stages. What are they?

Answer 12

pre-reproductive, reproductive, and post-reproductive.

Question 13

What is a cohort?

Answer 13

a small subpopulation sample of a larger population to make inferences about the whole.

Question 14

What is a metapopulation?

Answer 14

a metapopulation is a group of local subpopulations within a larger area or region.

Question 15

How are subpopulations connected?

Answer 15

subpopulations are connected through movement of individuals and interact by dispersal and gene flow.

Question 16

What is colonization?

Answer 16

colonization is the movement of individuals (via dispersal) from occupied patches to unoccupied patches and forms new subpopulations.

Question 17

The rate of colonization into suitable populations depends on two factors. What are these factors?

Answer 17

1. the proportion of empty patches
2. proportion of patches providing colonizers

Question 18

What is extinction?

Answer 18

extinction is the complete loss of a subpopulation from an occupied patch.

Question 19

What does it mean if:

colonization rate = extinction rate ?
colonization rate > extinction rate ?
colonization rate < extinction rate ?

Answer 19

1. the number of patches occupied remains static at equilibrium.
2. more patches will be occupied until the median (~50% of patches are occupied) is reached.
3. will be brought back the median.

Question 20

What is a synchronized event?

Answer 20

synchronized event acts on EVERY subpopulation within a metapopulation at the same time and may pose an extinction risk for the entire metapopulation