Population Ecology

Question 1

What is ecology?

Answer 1

study of interactions of organisms with their environment

Question 2

What are the 2 components in the environments?

Answer 2

Biotic and Abiotic

Question 3

What are the biotic components?

Answer 3

Living organisms

Question 4

What are the abiotic components?

Answer 4

Non- living things

Question 5

From Greek words oikos (house) + logos (study): originally, study of _________________________-

Answer 5

organisms in their natural “homes”

Question 6

___________ is where organism lives

Answer 6

habitat

Question 7

population: a group of individuals of the ____________________________________.

Answer 7

same species occupying a given area

Question 8

____________: number of individuals per unit area (e.g. no./hectare or no./m2)

Answer 8

Density

Question 9

_________________: three possibilities: uniform (or even), random, or clumped

Answer 9

Distribution in space

Question 10

What are the population characteristics?

Answer 10

Distribution in space and Density

Question 11

What are the spatial distribution?

Answer 11

uniform; random; clumped

Question 12

Which of the spatial distribution is the most common?

Answer 12

clumped

Question 13

What factors affect the size of the population?

Answer 13

natality (births)
mortality (deaths)
immigration (movement of individuals into a population
emigration (movement out of a population)

Question 14

What is the equation for the growth rate?

Answer 14

Growth rate = (births + immigration) - (deaths + emigration)

Question 15

In the growth rate equation, if these two sets of factors are ________, population size is stable: ______________

Answer 15

equal; zero population growth

Question 16

What would happen to a pair of sexually reproducing organisms in an ideal habitat with no limitations on food or space?

Answer 16

Exponential growth would take place

Question 17

What type of curve is exponential curve?

Answer 17

“J-shaped curve”

Question 18

Exponential growth does not occur for ______________

Answer 18

very long in nature

Question 19

What is the equation for exponential growth?

Answer 19

G = rN
G = growth rate
r = net productive rate
N = number of individuals in population

Question 20

What are the examples of limited resources?

Answer 20

food, space, etc.

Question 21

other factors may also regulate population density: _____________________________

Answer 21

weather extremes, disease, competition, predation, etc.

Question 22

populations actually level off at some size, “K”, defined as the ________________________

Answer 22

environmental carrying capacity

Question 23

In exponential growth, number of individuals that the environment _______________________

Answer 23

is able to support indefinitely

Question 24

What are the 2 types of growth?

Answer 24

Logistic growth and exponential growth

Question 25

What is the equation for logistic growth?

Answer 25

G = rN(K-N/K)
G = Growth Rate
r = net productive rate
K = carrying capacity
N = # of individuals in a popl.

Question 26

What factors limit the carrying capacity?

Answer 26

density-dependent factors and density-independent factors

Question 27

What is and are the density-dependent factors?

Answer 27

depend on the density of organisms
e.g.: nutrient supply: the more plants, the more nutrients taken up; supply becomes limiting — reduces population growth

Question 28

What is and are the density-independent factors?

Answer 28

limits on growth that act independently of density
e.g. late spring freeze, volcanic eruption

Question 29

What is competition for resources?

Answer 29

individuals may compete for limited resources

Question 30

What are examples of competition for resources?

Answer 30

birds set up territories, and males chase away all others of same species

Question 31

Predation, parasitism, disease can be __________, especially if _________- increases

Answer 31

powerful factors; density

Question 32

What are density-dependent population controls?

Answer 32

competition for resources and predation, parasitism, disease

Question 33

human growth over the last several hundred years has become _____________

Answer 33

exponential

Question 34

_______________, ___________, and _____________&___________ have raised carrying capacity

Answer 34

agriculture, technology, and medicine & sanitation

Question 35

for thousands of years, population was limited by _______________, _____________, and ___________

Answer 35

food resources, water supplies, and disease

Question 36

The human population still increasing ____________
overall growth rate is __________

Answer 36

exponentially; decreasing

Question 37

Survivorship curves graphically represent the _________________________

Answer 37

death rates of a population over a generation

Question 38

What are the different types of survivorship curves?

Answer 38

types I, II, and III

Question 39

What is survivorship curve type 1?

Answer 39

high survivorship through most of life; most deaths late, after reproduction

Question 40

What is survivorship curve type 2?

Answer 40

constant rate of death throughout lifespan

Question 41

What is survivorship curve type 3?

Answer 41

high early death rate; only a few make it to old age

Question 42

What population will have survivorship curve type 1?

Answer 42

typical of human populations with good health care

Question 43

What population will have survivorship curve type 2?

Answer 43

songbirds, lizards, small mammals, etc.

Question 44

What population will have survivorship curve type 3?

Answer 44

insects, marine invertebrates, many fishes