Transcript Populations 2016x

Populations 2016
-You need to know how population size is determined by births,
deaths, immigration, emigration and limiting factors.
-You need to be able to use data about population dynamics,
abiotic factors, and biotic factors to explain a change in carrying
capacity and population size in an ecosystem.
-You need to know that different types of organisms exist within
aquatic systems due to chemistry, geography, light, depth, salinity,
and/or temperature.
-You need to know the potential changes in an ecosystem resulting
from seasonal variations, climate changes and/or succession.
-You need to know the positive or negative consequences that
result from a reduction in biodiversity.
Active
Topic 3- Population
9/19 & 9/20
SC.912.L.17.5 Population size is determined by births, deaths,
immigration, emigration and limiting factors.
Daily Activity
Word Wall
Population
Dynamics
Birth
Death
Immigration
Emigration
Exponential Growth
Logistic Growth
•1. Intro Population Dynamics
Carrying Capacity
OUI •2. Practice Questions
Density
•3 Limiting Factors Activity-(Group)
Dependent
Density
Home LearningEcology – Shoology Exam
Evaluation: Teacher Observation &Limiting Factors Activity
Independent.
Mr. Suydam
Room # 43103
BIOLOGY
Producer
Brain Pop : Population Growth
• http://glencoe.mcgraw-hill.com/sites/dl/free/0078695104/160350/00050757.html
1.In 1553, Portuguese sailors released goats to graze on the grasses
on the island of St. Helena in the South
Atlantic in order to serve as a food source for sailors on passing
ships. A few years later goats were plentiful, but many of the native
plants and animals no longer inhabited the island. Which of the
following is the most likely cause for the disappearance of the plants
and animals?
A. The goats fed on the other plants and animals.
B. Sailors more frequently visited the island for food and destroyed
the vegetation.
C. The goats brought diseases to the island that killed the native
plants and animals.
D. The goats had no natural predators on the island, so they
reproduced rapidly and overgrazed.
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working
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work
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Limiting factors- are environmental conditions that limit
the growth, abundance, or distribution of an organism
or a population of organisms in an ecosystem.
• A population is a group
of similar organisms,
Limiting Factors for the marine environment are?
Light Nutrients
Oxygen Temperature
Phytoplankton
Depth increase:
Temperature- __________
Pressure- _____________
# of Organisms- _________
Sketch Ocean Zones
http://www.census.gov/popclock/
Population Pyramids Show Growth Rates.
Slow Growth
Rapid Growth
Population Pyramids
SC.912.L.17.5
Organisms, Populations, and Ecosystems
Analyze how population size is determined by births, deaths, immigration, emigration, and
limiting factors (biotic and abiotic) that determine carrying capacity.
Carrying Capacity
• maximum population size of the species that
the environment can sustain indefinitely.
https://www.youtube.com/watch?v=8FPMP41LYJ8
Population Growth
Three factors can affect population size:
• the number of births
• the number of deaths
The number of individuals that• Enter (immigration)
• Exit (emigration)
• A population can grow when its birthrate is
greater than its death rate. BR>DR
Change in
Population
=
Can you think of something in nature that exhibits exponential
growth? Logistic growth?
Population will follow two
general paths:
• When faced with
unlimited resources
it will grow
exponentially
• When faced with
limited resources it
grow logistically
“Boom and Bust”
“Boom then Stable”
Exponential growth of
bacteria
Which Letter ?
J-shaped curve.
Logistic Growth
As resources become less available, the growth of a
population slows or stops.
Logistic growth occurs when a population's growth slows
or stops following a period of exponential growth.
Which Letter ?
S-shaped curve.
Environmental
resistance
Population size (N)
Carrying capacity (K)
Biotic
potential
Exponential
growth
Time (t)
Growth of a population of fur seals
What
the
What
is is
the
carrying
capacity
carrying
of sheep?
capacity
of
fur seals?
Limiting Factors of the Homestead Glades
* Class Set
OBJECTIVES: Students will learn how an ecosystem may be
affected by limiting factors; students will explain how carrying
capacity can differ in various scenarios
QUESTION: What types of factors limit the carrying capacity
of the system in the homestead glades ecosystem?
MATERIALS: masking tape ,yard stick or measuring tape,
pipe cleaners bent into 10 x 10 cm squares to represent the owls,
colored pencils, graph paper , large bag of pinto beans
(or other dried beans) to represent the mice, student data sheet.
BACKGROUND: In nature, populations of organisms rarely grow uncontrolled. Each
ecosystem has a carrying capacity or number of organisms it can sustain. Limiting Factors are
biotic and abiotic factors that prevent the continuous growth of a population. Because of
limiting factors, the number of organisms in a population are often well below carrying
capacity. This activity will look at limiting factors found in the Cedar Glade ecosystem, and
their impact on population growth.
PROCEDURE:
1. Divide class into groups of four. Assign these roles:
a) bean counter (mice counter) – scatters beans between rounds and records the number of
beans caught. Beans represent mice.
b) Recorder – reads directions for the activity and records the data
c) female owl – stands outside the glade area, tosses the sampling square (to model the owl
feeding), collects all beans (mice) located inside the square
d) male owl – same role as female
2. With masking tape, mark off an area (approximately 4 ft. square) on the floor. This represents
an area in the glade where the owls will hunt.
3. Scatter 80 beans over the grid. Each bean represents a mouse in the glade.
4. The two pipe cleaner squares represent a male and female owl, which separately hunt the
area. Student should stand about one foot from the grid and toss the square into the grid.
5. Remove any beans that are inside the square. Repeat.
* Each “owl” has two chances to “hunt” (toss) each day.
6. Do the same thing with the other owl. This process represents hunting mice.
7. In nature, each owl hunts twice a day. In order to stay alive, each owl must eat at least 4
mice in a three day period! If fewer than 4 mice are eaten in any three-day period, the owl
grows too weak to hunt and dies.
Limiting Factors of the
Homestead Glades
Name(s)_____________________ _____________________ Date________
_____________________ _____________________ Per. ________
Investigation 1: Glade in early spring-conditions usually favorable for mouse population
A. Each owl hunts 2 times per day beginning with the female. Any mice caught must be
removed before the next owl hunts. Enter the numbers in Table 1.
B. Continue as long as there is a surviving owl. Enter an X in the appropriate box on the
table indicating the date of death (if it occurs).
Table 1:
Mice
Day
Day
Day
Day
Day
Day
Day
Day
Day
Day
Eaten
1
2
3
4
5
6
7
8
9
10
Female
Owl
Male
Owl
Total
Captured
Investigation 2: Lack of rain has led to drought like conditions in the glade. 25% of the mice
die (20 total). Remove these 20 from your area before the owls hunt.
A. Complete Table 2 for 10 days as in Investigation 1.
Table 2
Mice
Day
Day
Day
Day
Day
Day
Day
Day
Day
Day
Eaten
1
2
3
4
5
6
7
8
9
10
Male
Owl
Female
Owl
Total
Captured
Investigation 1
Favorable Spring
Conditions 80 Beans
Investigation 2
Drought Conditions
Remove 20 beans
1.How did the dry conditions affect the hunting success of the owls as compared with
Investigation 1? (Use data to compare).
http://rjknits.blogspot.com/2012/01/dissectin
g-owl-pellet.html
2. What do you predict would happen if the drought-like conditions had killed 50% of the
mice?
Investigation 3: The spring season this year has been a successful one for the Eastern Garter
Snake. Its numbers have increased by 25% and the owls are in direct competition with the
snakes for mice. Begin with 80 mice; remove 3 mice (beans) each day before each of the owls
hunt (6 removed total each day for male and female).
Table 3
Mice
Eaten
Male
Owl
Female
Owl
Total
Captured
Day
1
Day
2
Day
3
Day
4
Day
5
Day
6
Day
7
Day
8
Day
9
Day
10
1. How did the addition of competitors affect the survival rate of the owls?
2. What were some limiting factors that were used in this activity?
3. Give two examples of other limiting factors that would influence either the mouse or owl
population?
Investigation 3
Competition with
Snakes
read instructions
Snake eats 6 each time
before the owls…
Graph your total captured data using a line graph.
Data from table 1- normal activity – use a green color.
Data from table 2- drought activity – use a brown color.
Data from table 3- competition activity – use a red color.
# of Mice
Create a line graph
Days
1-10
Essential Questions: EQ
1.How does a population differ from a
community?
- A population is made of a group of
individuals and community of all the
individuals.
1.Describe one factor that can influence a
change in population size.
- Death- lowers population
- Emigration- lowers population
- Birth- increases population size.
- Immigration increases population size.
Last 10 Minutes
Time to use your
Cerebrum……
Number your paper
1-10
1
6
2
7
3
8
4
9
5
10
1. The size of the human population began to
increase exponentially after the
• A. bubonic plague.
• B. development of plowing and irrigation.
• C. Industrial Revolution.
• D. development of the first cities.
2. When the birthrate of a population
exceeds its death rate, the population
• A. decreases.
• B. Increases.
• C. stays the same.
• D. increases then decreases.
3. When an environment has reached its carrying
capacity for a certain population, which of the following
is true?
A. Growth and immigration rate is equal to death and
emigration rate.
B. Growth and immigration rate is greater than death
and emigration rate.
C. Growth and immigration rate is less than death and
emigration rate.
D. Growth rate is exponential.
4. Exponential growth in a population slows
down or stops as
• A. resources become limited.
• B. rate of immigration increases.
• C. of emigration decreases.
• D. birth rate increases.
• 5. Data on the immigration and emigration of a fish
species would be most helpful in determining which of the
following?
• A. biological magnification
• B. interspecies competition
• C. population of the species
• D. predator-prey relationships
6. The graph of a population of deer is shown below.
What can be concluded from this graph?
a. the deer population grew exponentially
b. the deer population grew at a constant rate
c. the deer population reached its carrying capacity
d. the deer population will never reach a carrying
capacity
7 .A population of rabbits experiences a large increase over time.
One researcher claims that this is because the number of gardens
near the woods has increased. Which statement is a valid
alternative explanation of the population increase?
A. Another species of rabbit has been introduced into the area.
B. The population has reached the carrying capacity of the area.
C. A conservation group has released a mated pair of hawks in the
area.
D. The passage of a leash law has kept predatory dogs from
roaming freely.
8. As the human population rises, the demand for popular fish,
like tuna, in grocery stores and restaurants has also gone up.
Many people enjoy eating these types of fish. How might
increasing the number of tuna caught affect the tuna fishery over
the long term?
A. The tuna population may decrease, but then rebound after the
tuna adapt.
B. The tuna population as a whole may decrease, but the
demand for tuna will also decrease.
C. The tuna population may decrease; therefore, fishing
restrictions will need to be implemented.
D. The tuna population as a whole may decrease, but individuals
may be larger due to less competition.
9. The pH of the water in several lakes in Norway and
Sweden had decreased to below 5.0 due to an increase in
acid rain. Which of the following is most likely to happen
in these lakes?
A. the decline of several fish populations.
B. an increase in numbers of fish
C. an increase in the amount of primary producers
D. increased predator-prey relationships
10. Which environmental factor would cause the greatest
Decrease in the number of species of plants and animals living in
some of the lakes in the United States?
A. increase in dissolved oxygen levels
B. global warming
C. ozone destruction
D. acid rain
9/ 18 & 9/21
Mr. Suydam
Active
Room #4313
Word Wall
Topic 3 - Population –Limiting factors
SC.912.L.17.5 Analyze how population size is determined by births, deaths, immigration,
emigration, and limiting factors (biotic and abiotic) that determine carrying capacity.
Abiotic
Biotic
Carrying
Capacity
Limiting Factors
-density
dependent
Daily Activity
•1. PPT –Limiting Factors
•2. Preview Activity
•3. Limiting Factors activity -.
* Practice Questions
HOME LEARNING – Population H/O - Due Next Class
TILT
-density
independent
______________
Food
Shelter
Water
Competition
Predation
Storms
Light
Temperature
Rabbit Population by Season
Evaluation: Teacher observation – Density Dependent Activity
BIOLOGY
1. An unusually warm spring leads to an increase in the
number of mice in a fertile valley. One result of this
population explosion is the loss of farmers’ crops due to
consumption by the mice. What would be another likely
result of the population increase of the mice?
A. Mice will fill a different niche in the ecosystem.
B. The following year the spring will be warm again.
C. Birds of prey that eat mice will become more numerous.
D. Animals that compete with mice will adapt to find new
niches.
Rabbit Population by Season
http://www.explorelearning.com/index.cfm?method=cResource.dspView&ResourceID=380&ClassID=1021137
What factors limit population
growth?
Limiting Factors
- limits the growth or
development of an organism
or a population.
1. Which limiting factor is shown in the chart below?
2. What are the optimal temperatures for each of the 3 fish?
3. Predict the effect global warming might have on the rainbow trout
species existence .
Limiting Factors
• a limiting factor can be a (abiotic
or biotic) factor
Producer
Describe some limiting factors for plants?
* Which of the following is a limiting factor in a
population of organisms.
A. reproductive replacement
B. life spans of the members
C. fluctuations in atmospheric temperature
D. availability of food
What are limiting factors in the ocean?
Euphotic Zone
Aphotic Zone
* Why are there so few aquatic plants and phytoplankton
that live at the bottom zones in the ocean?
• A. The ocean floor contains many decomposers.
• B. Most sunlight is absorbed before reaching these
levels.
• C. Water is a limiting factor.
• D. The temperature in these zones is extremely low.
B. Most sunlight is absorbed before reaching these levels.
Plants and phytoplankton are primary producers that rely on the sun to carry out
photosynthesis. The bottom zones of the ocean have little to no light.
Density Dependent Limiting Factors
Any factor limiting the size of a population whose effect
is dependent on the number of individuals in the
population.
For example, disease will have a greater effect in limiting
the growth of a large population, since overcrowding
facilitates its spread.
Examples:
Competition
Predation
Food & Water Shelter
Parasitism
Disease
• Competition
• When populations become crowded,
organisms compete for food, water space,
sunlight and other essentials.
These can
become limiting
factors
Density-Dependent Factors
• Predation
• Populations in nature are often controlled by predation.
Aphid
Density-independent factors are
environmental factors affecting a population regardless
of size, such as temperature and oxygen supply.
One Density-independent factors would be the impacts
of an earthquake on a pack of wild dogs.
The number of dogs does not affect the result of the
earthquake upon the dog population.
Density-Independent Factors
• Examples of density-independent limiting factors include:
• unusual weather
• natural disasters
• seasonal cycles
• certain human activities—such as damming rivers and clear-cutting
forests
Special Notes
• Human intervention or action may change
an ecosystem….
DENSITY
Independent (DI) or Dependent (DD)
Population
SIZE DOESN’T
MATTER
Population
SIZE MATTERS
DD
Bears feeding on salmon.
DI
Natural Disasters.
DD
Number of fish in a lagoon.
DI
Flooded trees near a river bank.
DI
A drought in a river in California’s fish population.
DD
Sick diseases pigs due to overcrowding.
DD
Owl catching a mouse.
DI
Death of a deer due to freezing.
LIMITING FACTORS
* Class Set
- to learn about various limiting factors that influence population dynamics
- to investigate which factors affect yellow perch in Lake Winnipeg
LIMITING FACTORS
All living things need food, water, shelter and space to survive. As long as organisms have all of these
things available to them their population will continue to grow. However, populations cannot grow
forever. Some form of environmental resistance will stop the population’s growth.
The form of environmental resistance is called a limiting factor since it limits the population. However,
limiting factors may also increase a population. We will look at many different limiting factors and
classify them into density independent factors and density dependent factors.
- natural disasters: disasters caused by nature
- density: organisms per unit area
- toxic: poisonous
- tail races: area of water located behind a dam
- aquatic: taking place in or on the water
- penetrate: to enter or force a way into
- depletion: the use or consumption of a resource
- turbid: degree of cloudiness of water
- tributaries: a stream that flows into a larger stream or other body of water
- invasive: moves in without right or permission, intrusive
TASKS:
Read the notes on limiting factors. Then, using the knowledge you have gained, read the next set of
notes to find all of the limiting factors that affect yellow perch in Lake Winnipeg.
Using the work sheet provided on page 4, try to identify as many limiting factors as possible
and classify them as density independent or density dependent factors.
Then answer the questions on pages 4 and 5.
DENSITY INDEPENDENT FACTORS
Density independent factors can affect a population no matter what it’s density is. For example:
natural disasters, temperature, sunlight, human activities, physical characteristics and behaviors of
organisms affect any and all populations regardless of their densities.
Natural disasters such as droughts, floods, hurricanes and fires can be devastating to aquatic life.
For example, a severe drought could lower the water levels of Lake Winnipeg and decrease its
carrying capacity. Thus, the fish population would decrease.
Temperature influences the activity and growth of organisms. Temperature also determines which
type of organisms can live in a lake. Usually, the higher the water temperature, the greater the activity
in a lake. However, all aquatic species have a preferred temperature range. If temperatures vary too
much out of this range the species will either die or move to a different location.
Temperature also influences the chemical properties of water. The rate of chemical reactions in the
water increases as temperature increases. For example, warm water holds less oxygen than cool
water, so even though there is more activity in warm water there may not be enough oxygen for the
activity to continue for long periods of time.
Sunlight can only penetrate to a depth of 30 meters in water. Thus most photosynthesis in
aquatic environments occurs near the surface. This means that most plants cannot grow if they
are at the bottom of a deep lake.
Human activities can also affect population dynamics. For instance, lake sturgeon spawn in fast
water and sometimes use the “tailraces” of hydroelectric dams. However, the water level in this
location often drops suddenly and the eggs die because they become exposed.
Physical characteristics of organisms can affect their population. Many organisms have adapted
and evolved in order to increase their chance of survival. For example, some species of fish have
colored markings to warn predators that they may be toxic. Or, some species use camouflage colors
to help them hide and avoid being eaten.
Behaviors of organisms can also affect their population. For example, some species migrate to find
new food sources or to mate. Some organisms create societies or feeding territories. For instance,
white bass live in schools and work together to drive emerald shiners to the surface for feeding. Some
species may have mating or courtship behaviors that affect their population.
white bass live in schools and work together to drive emerald shiners to the surface for feeding. Some
species may have mating or courtship behaviors that affect their population.
DENSITY DEPENDENT FACTORS
Density dependent factors can only affect a population when it reaches a certain density. For
example, competition, predation, disease, parasitism, crowding, and stress are all factors that only
affect populations with high densities.
Competition can occur between many organisms that live in the same habitat. Resources are limited
in a habitat so organisms must compete for food, water, space, and shelter. For example, both
northern pike and walleye prey on yellow perch and so they compete for the same food source.
However, this competition is only apparent when the populations of northern pike and walleye have
high densities OR the population of yellow perch has a low density.
Predation occurs when the population density of predators is high. The predators will consume their
prey and increase their own population. However, the population of the prey will decrease. On the
other hand, the lack of predation (when the population density of predators is low) will cause
problems for the prey’s population. When there are few predators, the prey’s population increases
very quickly and this can lead to the depletion of resources and increase disease.
Disease in a population increases with the density of that population. High densities makes it
easier for parasites to find hosts and spread the disease.
Parasitism is a relationship in which one species benefits at the expense of the other. A parasite is
an organism that lives in or on another organism (called a host) to get nourishment.
While the parasite benefits from this relationship the host is harmed or killed.
Crowding only occurs at high densities. Over-crowding can cause depletion of resources,
disease and stress. Stress usually has a negative effect on populations. Stress can make organisms
weak and more prone to disease.
YELLOW PERCH IN LAKE WINNIPEG
Located 217 m above sea level, Lake Winnipeg is a shallow lake composed of two basins: a
wide north basin and a narrow south basin. On average, Lake Winnipeg is only 12 meters deep
and receives 517 mm of precipitation annually. Lake Winnipeg provides a habitat for over
50different species of fish including yellow perch, chestnut lampreys and rainbow smelt.
Yellow perch prefer water that has little current. They can tolerate moderate tubidity.
Also, they prefer a temperature range of 18 to 20 degrees Celsius. If the temperature of the
water varies too much above this range, yellow perch will either move to a new location or die.
Yellow perch spawn in May or early June when water temperatures are above 6 degrees
Celsius. First, they migrate to tributaries and then several males attend a female while she
releases her eggs.
Yellow perch can grow to 302 mm in length. Their life span is approximately 9 years. If there is
a lack of resources or too many of them (over-population), yellow perch adapt by stunting. This
means that instead of starving, they simply do not grow as large as normal. Thus, they are able
to live off less food. Yellow perch feed in midwater or on the bottom of Lake Winnipeg. They
eat a wide variety of invertebrates, and fish such as emerald shiners. The eyes of yellow perch
allow them to see almost 360 degrees around them. Thus, they are better able to spot their prey
and evade predators. In Lake Winnipeg, yellow perch are eaten by northern pike and walleye.
They are also caught for food by commercial fishers and anglers. Chestnut lampreys are also
found in Lake Winnipeg. Lampreys are parasitic fish that attach to other species of fish (such as
yellow perch) to feed on their blood and tissues.
Recently, rainbow smelt have been introduced into Lake Winnipeg. Rainbow smelt are a very
invasive and competitive species. They have been thought to have caused a decrease in the
emerald shiner population.
Lake Winnipeg provides a home for many species of fish. However, a severe drought could
disrupt this ecosystem greatly. Lake Winnipeg’s water level would drop, the temperature could
change and it could become more turbid. Thus, the carrying capacity of the lake would change.
But, in its current condition, Lake Winnipeg is an excellent habitat for many species of fish.
QUESTIONS:
Name(s) - ______________________ ________________________
_____________________
________________________
Date- ________ Per. _____
1) Explain the difference between density independent and density dependent limiting factors.
2) From the article “Yellow Perch in Lake Winnipeg”, identify and describe 2 limiting factors
for each: density independent and density dependent.
Density Independent Limiting Factors:
1.________________________________________2. __________________________________________
Density Dependent Limiting Factors:
1.________________________________________2. __________________________________________
3) Each of the statements below involves a situation that will affect the growth of a population.
Classify each of the statements as DD (density dependent) or DI (density independent),
then give a reason for your choice.
a. Rainbow smelt and yellow perch attempt to occupy the same area. The more aggressive smelt survive; the
perch do not. DD or DI Justification:______________________________________________________
b. A severe flood brings a lot of sediment and silt into Lake Winnipeg. The turbidity of the lake increases
greatly.
DD or DI Justification:______________________________________________________
c. A drought decreases the water level in Lake Winnipeg. The carrying capacity of the lake decreases.
DD or DI Justification:______________________________________________________
d. Due to the introduction of rainbow smelt, Lake Winnipeg becomes crowded and some fish species do not
survive
DD or DI Justification:______________________________________________________
e. Since northern pike prey on yellow perch, an increase in the perch population causes an increase in the pike
population. DD or DI Justification:______________________________________________________
f. Many fish die due to an increase in water temperature.
g. Due to over-fishing, the number of walleye in Lake Winnipeg decreases.
DD or DI Justification:______________________________________________________
h. A population is growing quickly when parasites cause disease to spread quickly.
DD or DI Justification:______________________________________________________
i. Since lake sturgeon migrate long distances to spawn, many do not survive the trip.
DD or DI Justification:______________________________________________________
Choices – Use the following statements to respond to the above scenarios

They are not in correct order
DI - natural disasters affect all populations regardless of density
DI - natural disasters affect all populations regardless of density
DD - crowding only occurs at certain densities
DD - parasitism only affects certain population densities
DI - human activities affect all population densities
DI - temperature affects all population densities
DD - predation only occurs at certain densities
DD - competition between species only occurs at certain densities
DI - behaviors of organisms affect all population densities
On the back staple each your groups PLAYER CARDS.
Practice questions: * DO AS A GROUP.
1.___ Angel was trying to explain carrying capacity to her mother. Which of the following descriptions is
accurate? Carrying capacity is :
A. the greatest number of individuals that an area can sustain over the long term.
B. the ability of an environment to accommodate a growing population.
C. the maximum number of individuals that an ecosystem can sustain.
D. the maximum number of species that can co-exist in an area.
2.___ Jenn is studying a population of fish found in a pond that has a decreasing carrying capacity.
Which of the following factors would not decrease the carrying capacity of her fish?
A. drought
B. flooding
C. food shortages
D. a freeze
3. ___
An animal’s population decreases from 800 individuals to 600 individuals.
Which of the following could explain this change in population size?
A. The population size of the animal’s predator increased.
B. The emigration rate of the animals from the population decreased.
C. The number of breeding pairs in the animal’s population increased.
D. The number of species competing with the animal for food decreased.
4. ____ After the Aswan High Dam was built on the Nile River, the rate of parasitic blood fluke infection
doubled in the human population near the dam. As a result of building the dam, the flow of the Nile changed.
This changed the habitat, which resulted in an increase in its population of a certain aquatic snail. The snails,
which were infected, released larvae of the fluke. These larvae, then infected humans. This situation best
illustrates that:
A. the influence of humans on a natural system is always negative in the long term
B. the influence of humans on a natural system can have unpredictable negative impacts
C. human alteration of an ecosystem does not need to be studied to avoid ecological disaster
D. human alteration of an ecosystem will cause pollution and loss of finite resources
5. ____ When fertilizers run off farmland into streams and ponds, the nitrogen content of the water increases.
This can lead to rapid growth of algae in a process called eutrophication. How can this process affect other
organisms in the water?
A. Oxygen is used up as algae is decomposed, reducing the amount available to other organisms.
B. The water becomes better able to support aerobic organisms.
C. The algae provide food for fishes and other organisms, leading to decreased algae populations.
D. The extra nitrogen provides additional food for the other organisms, increasing their population.
6. What is the carrying capacity for the fish
population shown in the graph to the right?
_________
7. List 2 limiting factors that may have
caused the fish to reach carrying capacity.
1. _______________________
2. _______________________
8. Predict how acid rain would affect the
fish population shown to the right.
________________________________
________________________________
9 What type of curve is shown in the graph
to the right?
Exponential or Logistic
10. Draw a dashed line ( - - - - - ) line in the graph above that
represents the carrying capacity of the fish.
http://www.gov.mb.ca/conservation/sustain/boardgame.pdf
Game : Limiting Factors
• 1) Groups of 4 students will pretend to be a fish and play the Fish Limiting
Factors board game.
• 2) Each group will need one die
• 3) Each student will cut out his or her fish token or other object as a
marker.
• 4) Students will place their tokens at the start, take turns rolling the die
and moving the number of spaces indicated on the die.
• 5) They will follow all directions written on spaces they land on.
• 6) Students will use the playing card to keep track of all limiting factors
they experience during the game (and to classify them as density
independent or density dependent).
Playing Card
• Staple your card to the hand out
Limiting factors of Homestead Glades
Density Independent Limiting Factors
Density Dependent Limiting Factors
http://www.gov.mb.ca/conservation/sustain/boardgame.pdf
Essential Questions:
1.Distinguish between abiotic and ibiotic
limiting factors ?
Abiotic- Non Living.
Biotic – Living
2. Identify 3 limiting factors that affect deer
and identify if it is ABIOTIC or BIOTIC.
Water---- ABIOTIC
Food---- BIOTIC
Shelter----- ABIOTIC
Freezing Winter- ABIOTIC
1-10
1
6
2
7
3
8
4
9
5
10
1. Which of the following would be
a limiting factor affecting the
panda population of China?
• A. programs that educate people about
endangered species
• B. capture of some pandas for placement in zoos
• C. laws protecting habitat destruction
• D. a disease that kills bamboo plants
2. Within a limited area, if the population of a
predator increases, the population of its prey is likely
to
• A. increase.
• B. decrease.
• C. remain about the same.
• D. become extinct.
• 3. Which of the following is a densityindependent factor affecting populations?
• A. predation
• B. disease
• C. a destructive hurricane
• D. parasites
4. How does the predator-prey relationship affect a
population?
A. The predators and prey are in competition with each
other.
B. Usually either the predator or the prey will become
extinct.
C. The predator species usually has exponential growth.
D. The relationship controls the population size of both
species.
• 5. The number of pythons found throughout Everglades
National Park has increased in recent years. These huge
snakes are not native to Florida and are believed to have
been released into the wild by pet owners. Wildlife
biologists have initiated attempts to capture and remove
these pythons. Which statement best explains the biologists'
reasons for removing these pythons from the Everglades?
• A. The pythons could upset the territorial boundaries of
native organisms.
• B. The pythons could adapt to overcome diseases common
to native snakes.
• C. The pythons could prey on native organisms and cause
native population to decline.
• D. The pythons could begin to interbreed with native snakes
and produce a more successful species.
6. The common brush tail possum is a marsupial
native to Australia. This possum was introduced to
New Zealand where it had no natural predators and
had an abundant food supply. Which of these likely
occurred a few years after the introduction of this
possum to New Zealand?
• A. The possums became extinct.
• B. The possums developed shorter life spans.
• C. The possum population grew to a larger size.
• D. The possum population evolved into a different
species
Many insects, such as mosquitoes and dragonflies,
7.
spend their juvenile stage as aquatic larvae before
becoming winged and airborne adults. Most years,
these insects are extremely abundant in the Arctic
tundra in summer. What might account for this?
A. Adult insects spend the long Arctic winter laying
thousands of eggs under the ice of frozen ponds.
B. Many insects migrate long distances to take
advantage of good breeding areas in the tundra.
C. Pools of water which make good breeding areas
are plentiful in summer as the permafrost melts.
D. Summer rains in the Arctic tundra replenish
breeding ponds that dried up during the winter.
8.A population of deer becomes stranded on a remot
e island. Eventually, the population
reaches the island’s carrying capacity. At this
point, the birth and death rates are
A. relatively equal.
B. crashing.
C. density dependent.
D. density independent.
9. The populations of fish and amphibians in a lake more than 100
miles downwind from a coal- fired power plant suddenly began to
decline. Biologists sampled the water in the lake and found that it
had a pH of 2.4. What conclusions could the biologists draw from
their finding?
A. Acid rain that had fallen on the lake had to have come from a
pollution source close to the lake.
B. Pollutants from the power plant could be making the lake water
too alkaline to support life.
C. The pH of the lake water was normal, so the decline in fish and
amphibian populations had some other cause.
D. The lake water had become very acidic, which could be linked to
emissions from the distant power plant
10. Two species of finches are in competition for the limited
resources of an ecosystem.
One species eats fruit and the second species eats seeds. If a third
species of herbivore finches moves into the area, how will the
ecosystem change?
A. Resources will be more abundant.
B. Water will become more available.
C. The climate of the ecosystem will change.
D. Fruit and seed resources will become less abundant
Review
Rabbit Population by Season
• http://www.explorelearning.com/index.cfm?method=cResource.dspView&ResourceID=380
Population
Escambia Biology
• http://ecsd-fl.schoolloop.com/L.17.5
Practice Questions
Time For the Sim
• http://glencoe.mcgraw-hill.com/sites/dl/free/0078695104/383928/BL_04.html
Name(s) ___________________________________________ Date- _________ Period____
Title: How does competition affect population growth?
http://glencoe.mcgraw-hill.com/sites/0078695104/student_view0/unit1/chapter4/virtual_labs.html#
The term protozoan means “ F_______ A_________”
Read the Purpose and the Objectives
Write a Problem Statement from information gathered the purpose.
______________________________________________________________________________
______________________________________________________________________________
Research Click on Information on the bottom and take notes below:
1. Make a hypothesis about how you think the two species of Paramecium will grow alone and
how they will grow when they are grown together.
Hypothesis:___________________________________________________________________
______________________________________________________________________________
Procedure Read and carry on with the activity.
Data Record in the table below.
When the table is complete, transfer the data to the computer table and select graph.
http://glencoe.mcgraw-hill.com/sites/dl/free/0078695104/383928/BL_04.html
Make a sketch of - P. aurelia
P. caudatum
Do the parameciums in the activity look anything like the real paramecium? ______________
Analysis – * use the graph to assist you
2. On what day did the Paramecium caudatum population reach the carrying capacity of the
environment when it was grown alone?_____________________________________________
How do you know?____________________________________________________________
3. On what day did the Paramecium aurelia population reach the carrying capacity of the
environment? __________________________________________________________________
How do you know?______________________________________________________________
4. Explain the differences in the population growth patterns of the two Paramecium species.
______________________________________________________________________________
_____________________________________________________________________________
5. What does this tell you about how Paramecium aurelia uses available resources?___________
_____________________________________________________________________________
6. Describe what happened when the Paramecium populations were mixed in the same test tube.
______________________________________________________________________________
______________________________________________________________________________
Do the results support the principle of competitive exclusion?___________________________
____________________________________________________________________________
7. Explain how this experiment demonstrates that no two species can occupy the same niche.
______________________________________________________________________________
______________________________________________________________________________
What would you rate this activity? 1 2 3 4 5 6 7 8 9 10
• Competition
• When populations become crowded,
organisms compete for food, water
space, sunlight and other essentials.
Active
Topic 3- Population
Word Wall
9/16
SC.912.L.17.5 Population size is determined by births, deaths,
immigration, emigration and limiting factors.
Essential Questions: EQ
1. How does a population differ from a community?
2. Describe one factor that can influence a change in
population size.
Population
Dynamics
Birth
Death
Immigration
Emigration
Exponential Growth
Logistic Growth
Carrying Capacity
Daily Activity
OUI
Trophic
Levels.
•1. Intro Population Dynamics
•2. Practice Questions
•3 Limiting Factors Activity-(Group)
Home Learning- Populations H/O
Evaluation: Teacher Observation &Limiting Factors Activity
Mr. Suydam
Room # 4313
BIOLOGY
A lesson on overpopulation
 Kaibab national forest - Arizona - deer
 1906 - stable population of 4,000 deer
- bounty was placed on their predators
 (1906-23) deer population swells and overgrazing begins
-- over 6,000 predators killed
 (1924-25) of the 100,000 deer present -- over 75% die chiefly of starvation & malnutrition
 1939 - fewer than 10,000 deer remained
 ** Destruction of natural enemies is not always good for
a species -- it can lead to its extinction or near
extinction.
 (Now for the Activity)