lecture 13: What is a population?

Question 1

What is a population?

Answer 1

A group of individuals of a single species inhabiting a specific area

Question 2

What are some characteristics that all populations have?

Answer 2

• Density
• Distribution
• Other demographic charactersitics

Question 3

What is Density in regards to a population?

Answer 3

• number of individuals per unit area

Question 4

What is Distribution in regards to a population?

Answer 4

Size, shape, and location of area occupied by population

Question 5

What are the other demographic characteristics held by a population

Answer 5

Age & sex ratios, birth & death rates, immigration and emigration rates, growth rates.

Question 6

What is absolute density?

Answer 6

The number of individuals of a population per unit area

Question 7

What is ecological density?

Answer 7

The number of individuals of a population per unit area of suitable habitat

(moose per hectare of forest)

Question 8

What limits a populations distribution?

Answer 8

The geographic distribution of a population is limited by the physical environment.

So a species can only live in areas where its niche requirements are fulfilled.

Question 9

What are the three reasons why species aren’t living in all spaces?

why are they isolated to only certain locations

Answer 9

1. All organisms have limited energy and resourses
2. it takes extra energy to survive and reproduce in region on the edge of their niche
3. Therefore, organisms don’t usually bother spreading out

Question 10

What dose teh dispersal of a population affect?

Answer 10

It can alter the distributions and local population densities

Question 11

What are the two major categories of dispersal?

Answer 11

immigration: Movement into a local population

Emigration: movement out of a local population.

Question 12

Is migration dispersal?

Answer 12

no

Question 13

What is migration?

Answer 13

Migration is the seasonal movement of individuals from one location to another.

Question 14

What is dispersal?

Answer 14

The permanent movement from one population to another

Question 15

What is the issue with killer bees that have been moving up from central america?

Answer 15

Aggressive compared to standard farm bees

Can create larger colonies because of an excess of food

Also form massive swarms to protect their hives.

Question 16

In theory, Dispersal will allows a species range to move along with what?

Answer 16

The climate that their niche is within.

Question 17

What is the leading force of population dynamics?

Answer 17

Climate.

Question 18

What is dispersal a response of?

Answer 18

Changing of food supply

Question 19

What are the two responses seen by predators when food supply is altered?

Answer 19

Functional response

Numerical response

Question 20

What is a numerical response?

Answer 20

Change in density of predator populations in response to changes in prey density.

Question 21

What are the two drivers of numerical responses?

Answer 21

Reproduction & Dispersal

Question 22

What is a reproduction based numerical response?

Answer 22

Time lag between peak prey population and peak predator population.

Question 23

What is a Dispersal based numerical response

Answer 23

no time lag between peak predator and prey populations.

Question 24

Mountain pine beetle is spreading to
Alberta, wreaking havoc along the way.
What do you think the driving factor of their
dispersal is?

A. They are a non-native species, like the
Africanized honey bee example
B. Climate change, like the maple and
hemlock example
C. Food availability, like the kestrel/owl and
vole example

Answer 24

B. Climate change, like the maple and

hemlock example

Question 25

What is a meta population?

Answer 25

A meta-population is made up of a group of subpopulations living on patches of habitat connected by an exchange of individuals.

Question 26

What is a requirement for meta populations to form?

Answer 26

The populations need to be able to disperse from one population to another.

Question 27

If there is no dispersal between populations, then can it be considered a meta population?

Answer 27

No it cannot,

Question 28

What are the characteristics of a distribution pattern within a small scale

Answer 28

On smaller scales (< few hundred meters), the
individuals of a population are distributed in
patterns that may appear to be random,
regular/even, or clumped.

Question 29

What are the characteristics of a distribution pattern within a large scale

Answer 29

The populations are clumped. (around areas of ideal conditions)

this is over an area which there is substantial environmental change

Question 30

What is a random distribution?

Answer 30

Seen within small scales,

individuals have an equal change of living anywhere within an area.

Question 31

What is a regular distribution?

Answer 31

Seen within small scales,

Individuals are uniformly spaced.

Question 32

What is clumped distribution?

Answer 32

Seen within small scales,

individuals have a higher probability of being in some areas versus others.

Question 33

What is the common understanding of large scale distributions of populations?

Answer 33

They are populations that are distributed over scales in which there is significant environmental variation

Question 34

True or false:
All populations have characteristics such as
density, distribution, and demographics

Answer 34

True

Question 35

True or false:
Density is defined as the number of individuals
per unit area. Can be measured as absolute
density (/area) or as ecological density
(/habitat area)

Answer 35

True