Bell Work Bell Work • Main word/ idea: Population(s) Main word/ idea: Population(s) 1. Write as much information as you can 1. Write as much information as you can about:_ about:_ ________________________________ ________________________________ 2. A ______________________________is like a 2. A ______________________________is like a _____________________________ because: _____________________________ because: 3. Describe why it is important to study 3. Describe why it is important to study ________________________________? ________________________________? 4. What are some important characteristics of 4. What are some important characteristics of _______________________________________? _______________________________________?
Transcript
Bell WorkBell Work
• Main word/ idea: Population(s)Main word/ idea: Population(s)1. Write as much information as you can 1. Write as much information as you can
2. A ______________________________is like a 2. A ______________________________is like a _____________________________ because:_____________________________ because:
3. Describe why it is important to study 3. Describe why it is important to study ________________________________?________________________________?
4. What are some important characteristics of 4. What are some important characteristics of
Chapter 19 pg 236-237Chapter 19 pg 236-237Characteristics of populationsCharacteristics of populations
ObjectivesObjectives
• TLW: review definition of population.TLW: review definition of population.
• TLW:TLW: List the characteristics used to List the characteristics used to describe a population.describe a population.
ObjectivesObjectives
• TLW: review definition of population.TLW: review definition of population.
• TLW:TLW: List the characteristics used to List the characteristics used to describe a population.describe a population.
• TLW: create science vocabulary TLW: create science vocabulary cards for this chapter.cards for this chapter.
What is population What is population biology? biology?
It is the study of how and why It is the study of how and why populations changepopulations change
Define populationDefine population
A PopulationA Population
• Group of Group of organisms of the organisms of the same species same species living in the living in the same place at same place at the same timethe same time
• Individuals may Individuals may come and go, come and go, but the but the population can population can remain the sameremain the same
Characteristics of Characteristics of PopulationsPopulations
Important characteristics of a Important characteristics of a populations ability to survive is populations ability to survive is based upon:based upon:– Food supplyFood supply– Predation and diseasePredation and disease– Birth rateBirth rate– Death rateDeath rate– ImmagrationImmagration– EmmagrationEmmagration
Today’s AssignmentToday’s Assignment
• Period 1:Period 1:– Reading assignmentReading assignment– Define and draw a picture to showDefine and draw a picture to show
•PopulationPopulation
•LagLag
•Exponential (log)Exponential (log)
•Death phaseDeath phase
•Sigmoidal population growth curve (S curve)Sigmoidal population growth curve (S curve)
•ImmagrationImmagration
•EmigrationEmigration
Today’s AssignmentToday’s Assignment
• Science vocabulary card group projectScience vocabulary card group project
• Words for project:Words for project:– PopulationPopulation– ImmigrationImmigration– EmigrationEmigration– Exponential growthExponential growth– Limiting FactorLimiting Factor– Carrying capacityCarrying capacity– Density-dependent factorDensity-dependent factor– Density –independent factorDensity –independent factor
Bell Work
How can you determine the size of a population of organisms when the organisms move around and are hard to locate?
Population Density & Sampling Techniques
Objectives
• TLW: simulate the Mark-Recapture technique to determine population size.
Vocabulary
• Quadrants
• Indirect counting
• Mark-recapture
Review: Population Density
• The number of individuals of a species per unit or area or volume.
• How do we measure the number of individuals in a given area?
• In most cases it is impractical or impossible to count all the individuals in a population.
• As a result, scientists use a number of sampling methods: Quadrants, indirect counting, and Mark- Recapture.
Sampling Techniques
• Quadrants– Count # of
species in a particular area.
– Move Quadrant & repeat process
– Next, average results to get a population estimate
Sampling Techniques
• Indirect counting– Used when organisms
move around a lot and are too difficult to see.
– Involves counting nests, burrows, tracks, etc.
Ex. African Termite population: Size and # of mounds are counted instead of individuals
Sampling Techniques
• Mark – Recapture– Trap animals for study– Tag them– Release individuals– Trap animals again,
counts # of marked and unmarked to get an estimate of population size.
Today’s Activity
• Simulate the Mark-recapture sampling method.– Packums: determining population size
Bell WorkBell Work
• Take a couple of minutes and update Take a couple of minutes and update your I-notebook:your I-notebook:– Table of contentsTable of contents– Loose papersLoose papers– Number pages, etc.Number pages, etc.
EcologyEcology
Population GrowthPopulation Growth
ObjectivesObjectives
• TLW:TLW: Identify factors that affect Identify factors that affect population size.population size.
• TLW:TLW: Differentiate between Differentiate between exponential growth and logistic exponential growth and logistic growth.growth.
VocabularyVocabulary
• ImmigrationImmigration
• EmigrationEmigration
• Exponential GrowthExponential Growth
• Logistic GrowthLogistic Growth
Population GrowthPopulation Growth
• Populations can increase in number Populations can increase in number or decrease in number.or decrease in number.– Factors that affect population size:Factors that affect population size:
•Number of birthsNumber of births
•Number of deathsNumber of deaths
•And number of individual entering or leaving And number of individual entering or leaving the population.the population.
Population GrowthPopulation Growth
• More births than deaths = population More births than deaths = population growthgrowth
• More deaths than birth = population More deaths than birth = population declinedecline
• Birth rates = death rates = Birth rates = death rates = population stays the samepopulation stays the same
Population growthPopulation growth
• Immigration:Immigration: the movement of the movement of individuals into an area, can cause a individuals into an area, can cause a population to grow.population to grow.
• Emigration:Emigration: the movement of the movement of individuals out of an area, can cause individuals out of an area, can cause a population to shrink.a population to shrink.
Population Growth ModelsPopulation Growth Models
Population Growth ModelsPopulation Growth Models
• There are two models that are used There are two models that are used to explain population growth:to explain population growth:– Exponential growth modelExponential growth model– Logistic growth modelLogistic growth model
Population Growth ModelsPopulation Growth Models
• If resources are unlimited, population If resources are unlimited, population will grow exponentially.will grow exponentially.
• Exponential growthExponential growth: when the : when the individuals in a population reproduce individuals in a population reproduce at a constant rate.at a constant rate.– Growth rate at first is slow, then as the Growth rate at first is slow, then as the
population gets larger it grows more population gets larger it grows more quickly.quickly.
– A J-shaped curve indicates that the A J-shaped curve indicates that the population is in exponential growth.population is in exponential growth.
• Exponential growth: resources are Exponential growth: resources are unrestricted so the given population quickly unrestricted so the given population quickly grows.grows.
Turn to your neighbor: Turn to your neighbor: What is exponential What is exponential
growth?growth?
Can a population continue to Can a population continue to grow and grow? grow and grow?
Why not?Why not?
Population Growth ModelsPopulation Growth Models
•A population cannot continue to grow at an exponential rate due to limited resources such as:– Food shortages– Lack of space– Accumulation of own waste products– Lack of other resources like oxygen,
living space etc.
Population GrowthPopulation Growth
• As resources become less available, As resources become less available, the growth rate of a population slows the growth rate of a population slows or stops, called or stops, called logistic growthlogistic growth..– The growth pattern curve is S-shapedThe growth pattern curve is S-shaped
Logistic GrowthLogistic Growth
• Logistic growth: resources are limited so the Logistic growth: resources are limited so the growth of the population slows or stops.growth of the population slows or stops.
A comparison of the logistic growth A comparison of the logistic growth model and the exponential growth model and the exponential growth
modelmodel
Carrying capacity
Exponential growth
Logistic growth
Show me what you knowShow me what you know
1. The number of individuals of a 1. The number of individuals of a single species per unit is known as:single species per unit is known as:
A.A. Carrying capacityCarrying capacity
B.B. Logistic growthLogistic growth
C.C. Population densityPopulation density
D.D. Population growth ratePopulation growth rate
Show me what you knowShow me what you know
2. The movement of individuals into an 2. The movement of individuals into an area is calledarea is called
A.A. DemographyDemography
B.B. Carrying capacityCarrying capacity
C.C. ImmigrationImmigration
D.D. EmigrationEmigration
Show me what you knowShow me what you know
3. The range or area occupied by a 3. The range or area occupied by a population is itspopulation is its
A.A. Growth rateGrowth rate
B.B. Geographic distributionGeographic distribution
• Due tomorrow: Mark-recapture lab Due tomorrow: Mark-recapture lab write-upwrite-up
Bell WorkBell Work
• Some bacteria can reproduce every Some bacteria can reproduce every twenty minutes. Calculate the twenty minutes. Calculate the growth of a population of 10 bacteria growth of a population of 10 bacteria for 24 hours. (Don’t forget – 10 for 24 hours. (Don’t forget – 10 bacteria are at time 0)bacteria are at time 0)
EcologyEcology
Limits to Population GrowthLimits to Population Growth
ObjectivesObjectives
•TLW: Identify factors that limit population growth.
•TLW: Relate limiting factors and carrying capacity
VocabularyVocabulary
• Limiting factorsLimiting factors
• Carrying capacityCarrying capacity
Limits to population GrowthLimits to population Growth
• Limiting Factors:Limiting Factors:– A factor that causes A factor that causes
a population growth a population growth to decrease.to decrease.•CompetitionCompetition
Limits to Population GrowthLimits to Population Growth
• When environmental factors limit a When environmental factors limit a population’s growth rate the population’s growth rate the population is said to have reached its population is said to have reached its carrying capacitycarrying capacity..
• Carrying Capacity: Carrying Capacity: – The number of organisms in a The number of organisms in a
population that the environment can population that the environment can maintain or “carry” with no increase or maintain or “carry” with no increase or decrease in the population.decrease in the population.
– Birth rate = death rateBirth rate = death rate
Today’s AssignmentToday’s Assignment
• Grade I-notebooksGrade I-notebooks
• Lesson of the Kaibab activityLesson of the Kaibab activity
Bell Work (period 1)Bell Work (period 1)
• What is carrying capacity? Give an What is carrying capacity? Give an example.example.
Bell Work (periods 3-5)Bell Work (periods 3-5)
• Describe the most likely population Describe the most likely population growth curve you would expect to growth curve you would expect to see in a small town made up mainly see in a small town made up mainly of senior citizens. Compare this of senior citizens. Compare this growth curve to that of a small town growth curve to that of a small town made up of newly married couples in made up of newly married couples in their twenties. their twenties.
Week at a glanceWeek at a glance
• Tuesday: Tuesday: – Finish section 4.1Finish section 4.1– Study Guide 4.1 dueStudy Guide 4.1 due
• Wednesday: Wednesday: – Vocabulary quizVocabulary quiz– Human population growth section 4.2Human population growth section 4.2
– Chapter 4 testChapter 4 test– Parent Signatures in I-book dueParent Signatures in I-book due
Density factors and Density factors and Population GrowthPopulation Growth
Today’s ObjectiveToday’s Objective
• Differentiate between density-dependent Differentiate between density-dependent and density-independent limiting factors.and density-independent limiting factors.
• Describe how other organisms limit Describe how other organisms limit population growth.population growth.
• Three patterns of dispersal are random, Three patterns of dispersal are random, clumped, and uniform.clumped, and uniform.
Density factors and population growth
• How organisms are dispersed can be How organisms are dispersed can be important.important.
Random Clumped Uniform
• Reminder: population density describes Reminder: population density describes the number of individuals in a given the number of individuals in a given area.area.
Density factors and population growth
• There are two types of limiting factors There are two types of limiting factors that are related to dispersal: that are related to dispersal:
• Disease, for example, can spread more Disease, for example, can spread more quickly in a population with members that quickly in a population with members that live close together.live close together.
• Density-dependent factorsDensity-dependent factors include disease, include disease, competition, predators, parasites, and competition, predators, parasites, and food.food.
Density factors and population growth
• Most density-Most density-independent independent factors are abiotic factors are abiotic factors, such as factors, such as temperature, temperature, storms, floods, storms, floods, drought, and major drought, and major habitat disruption.habitat disruption.
• Density-independent factorsDensity-independent factors can affect can affect all populations, regardless of their all populations, regardless of their density.density.
Density factors and population growth
Organism Interactions Organism Interactions Limit Population SizeLimit Population Size
Organism Interactions Limit Population Size
• Population sizes are limited not only by Population sizes are limited not only by abiotic factors, but also are controlled by abiotic factors, but also are controlled by various interactions among organisms various interactions among organisms that share a community.that share a community.
• Organism interactions that can limit Organism interactions that can limit population size include: Predation, population size include: Predation, Competition, Crowding, and stressCompetition, Crowding, and stress
Predation affects population size
• Predation Predation increases the increases the chance that chance that resources will be resources will be available for the available for the remaining remaining individuals in a individuals in a prey population.prey population.
• However, when a However, when a predator consumes predator consumes prey on a large prey on a large enough scale, it enough scale, it can have a drastic can have a drastic effect on the size effect on the size of the prey of the prey population.population.
Competition within a population
• Competition is a density-dependent Competition is a density-dependent factor.factor.
• When only a few individuals compete for When only a few individuals compete for resources, no problem arises.resources, no problem arises.
• When a population increases to the point When a population increases to the point at which demand for resources exceeds at which demand for resources exceeds the supply, the population size the supply, the population size decreases.decreases.
The effects of crowding and stress
• When populations of certain organisms When populations of certain organisms become crowded, individuals may become crowded, individuals may exhibit symptoms of stress.exhibit symptoms of stress.
• These symptoms include aggression, These symptoms include aggression, decrease in parental care, decreased decrease in parental care, decreased fertility, and decreased resistance to fertility, and decreased resistance to disease.disease.
• They symptoms then become limiting They symptoms then become limiting factors for growth and keep populations factors for growth and keep populations below carrying capacity.below carrying capacity.
Today’s assignmentToday’s assignment
• Period 1: Section 4.1 worksheetPeriod 1: Section 4.1 worksheet
• Periods 3, 4, & 5: Periods 3, 4, & 5: – $2.00 summary$2.00 summary– Radio commercial activity due ThursdayRadio commercial activity due Thursday
Bell WorkBell Work
• List three density-dependent factors List three density-dependent factors and three density-independent and three density-independent factors that can limit the growth of a factors that can limit the growth of a population.population.
Bell work (periods 3-5)Bell work (periods 3-5)
• Why might a contagious virus that Why might a contagious virus that causes a fatal disease be considered causes a fatal disease be considered a density-dependent limiting factor a density-dependent limiting factor
Population EcologyPopulation Ecology
Chapter 4.2 pages 100-103Chapter 4.2 pages 100-103Human Population Human Population
ObjectivesObjectives
• TLW: describe what could happen if TLW: describe what could happen if the human population reaches it the human population reaches it carrying capacity. carrying capacity.
• TLW: examine how populations of TLW: examine how populations of different regions of the world different regions of the world compare with regards to numbers compare with regards to numbers and food availability. and food availability.
Key VocabularyKey Vocabulary
• DemographyDemography
• In the United States, a census is taken every In the United States, a census is taken every ten years.ten years.
World PopulationWorld Population
• One of the most useful pieces of data is the One of the most useful pieces of data is the rate at which each country’s population is rate at which each country’s population is growing or declining.growing or declining.
• These figures are the basis for These figures are the basis for demographydemography, the study of human , the study of human population size, density and population size, density and distribution, movement, and its birth distribution, movement, and its birth and death rates.and death rates.
• Human population growth is different than Human population growth is different than other organisms because humans have the other organisms because humans have the ability to change their environment.ability to change their environment.
• For example, man has learned to expand the For example, man has learned to expand the carrying capacity of his environment by carrying capacity of his environment by increasing food supply, combating pests and increasing food supply, combating pests and curing diseases.curing diseases.
• Today’s world population statistics:Today’s world population statistics:
Question: Can the Earth Question: Can the Earth support this ever increasing support this ever increasing
population?population?
Human population GrowthHuman population Growth
• Damage to the planet will eventually Damage to the planet will eventually reduce the carrying capacity for reduce the carrying capacity for humanity and slow the growth of the humanity and slow the growth of the human population.human population.
• What are some limiting factors for What are some limiting factors for the human population? the human population?
Ecology and growthEcology and growth
• Resources that are needed for life, such as Resources that are needed for life, such as food and water, could become scarce or food and water, could become scarce or contaminated.contaminated.
• Also, the amount of waste produced by a Also, the amount of waste produced by a population may become too difficult to population may become too difficult to dispose of properly.dispose of properly.
• These conditions can lead to stress on These conditions can lead to stress on current resources and contribute to the current resources and contribute to the spread of diseases that affect the stability spread of diseases that affect the stability of human populations both now and to of human populations both now and to come.come.
