Bell Work Main word/ idea: Population(s) Main word/ idea: Population(s) 1. Write as much information as you can about:_ ________________________________ 2. A ______________________________is like a _____________________________ because: 3. Describe why it is important to study ________________________________? 4. What are some important characteristics of _______________________________________?

Population Ecology Chapter 19 pg Characteristics of populations

Objectives TLW: review definition of population. TLW: review definition of population. TLW: List the characteristics used to describe a population. TLW: List the characteristics used to describe a population.

Objectives TLW: review definition of population. TLW: review definition of population. TLW: List the characteristics used to describe a population. TLW: List the characteristics used to describe a population. TLW: create science vocabulary cards for this chapter. TLW: create science vocabulary cards for this chapter.

What is population biology? It is the study of how and why populations change

Define population

A Population Group of organisms of the same species living in the same place at the same time Group of organisms of the same species living in the same place at the same time Individuals may come and go, but the population can remain the same Individuals may come and go, but the population can remain the same

Characteristics of Populations Important characteristics of a populations ability to survive is based upon: –Food supply –Predation and disease –Birth rate –Death rate –Immagration –Emmagration

Today’s Assignment Period 1: Period 1: –Reading assignment –Define and draw a picture to show Population Population Lag Lag Exponential (log) Exponential (log) Death phase Death phase Sigmoidal population growth curve (S curve) Sigmoidal population growth curve (S curve) Immagration Immagration Emigration Emigration

Today’s Assignment Science vocabulary card group project Science vocabulary card group project Words for project: Words for project: –Population –Immigration –Emigration –Exponential growth –Limiting Factor –Carrying capacity –Density-dependent factor –Density –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 Work Take a couple of minutes and update your I-notebook: Take a couple of minutes and update your I-notebook: –Table of contents –Loose papers –Number pages, etc.

Ecology Population Growth

Objectives TLW: Identify factors that affect population size. TLW: Identify factors that affect population size. TLW: Differentiate between exponential growth and logistic growth. TLW: Differentiate between exponential growth and logistic growth.

Vocabulary Immigration Immigration Emigration Emigration Exponential Growth Exponential Growth Logistic Growth Logistic Growth

Population Growth Populations can increase in number or decrease in number. Populations can increase in number or decrease in number. –Factors that affect population size: Number of births Number of births Number of deaths Number of deaths And number of individual entering or leaving the population. And number of individual entering or leaving the population.

Population Growth More births than deaths = population growth More births than deaths = population growth More deaths than birth = population decline More deaths than birth = population decline Birth rates = death rates = population stays the same Birth rates = death rates = population stays the same

Population growth Immigration: the movement of individuals into an area, can cause a population to grow. Immigration: the movement of individuals into an area, can cause a population to grow. Emigration: the movement of individuals out of an area, can cause a population to shrink. Emigration: the movement of individuals out of an area, can cause a population to shrink.

Population Growth Models

There are two models that are used to explain population growth: There are two models that are used to explain population growth: –Exponential growth model –Logistic growth model

Population Growth Models If resources are unlimited, population will grow exponentially. If resources are unlimited, population will grow exponentially. Exponential growth: when the individuals in a population reproduce at a constant rate. Exponential growth: when the individuals in a population reproduce at a constant rate. –Growth rate at first is slow, then as the population gets larger it grows more quickly. –A J-shaped curve indicates that the population is in exponential growth.

Exponential growth: resources are unrestricted so the given population quickly grows. Exponential growth: resources are unrestricted so the given population quickly grows. Exponential Growth

Generation# of bacteriatime min 3430min 4845min 5161hr 63275min 76490min min 92562hrs hrs , , ,5364hrs 18131, , , ,048,5765hrs 222,097, ,194, ,388,608

Turn to your neighbor: What is exponential growth?

Can a population continue to grow and grow? Why not?

Population 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 Growth As resources become less available, the growth rate of a population slows or stops, called logistic growth. As resources become less available, the growth rate of a population slows or stops, called logistic growth. –The growth pattern curve is S-shaped

Logistic Growth Logistic growth: resources are limited so the growth of the population slows or stops. Logistic growth: resources are limited so the growth of the population slows or stops.

A comparison of the logistic growth model and the exponential growth model Carrying capacity Exponential growth Logistic growth

Show me what you know 1. The number of individuals of a single species per unit is known as: A. Carrying capacity B. Logistic growth C. Population density D. Population growth rate

Show me what you know 2. The movement of individuals into an area is called A. Demography B. Carrying capacity C. Immigration D. Emigration

Show me what you know 3. The range or area occupied by a population is its A. Growth rate B. Geographic distribution C. Age structure D. Population denisty

Show me what you know 4. This graph represents A. Carrying capacity B. Exponential growth C. Logistic growth D. Limiting factor

Today’s assignment Problem-solving lab 4.1 (left-hand side) Problem-solving lab 4.1 (left-hand side) Exponential Growth Worksheet Exponential Growth Worksheet Due tomorrow: Mark-recapture lab write- up Due tomorrow: Mark-recapture lab write- up

Bell Work Some bacteria can reproduce every twenty minutes. Calculate the growth of a population of 10 bacteria for 24 hours. (Don’t forget – 10 bacteria are at time 0) Some bacteria can reproduce every twenty minutes. Calculate the growth of a population of 10 bacteria for 24 hours. (Don’t forget – 10 bacteria are at time 0)

Ecology Limits to Population Growth

Objectives TLW: Identify factors that limit population growth. TLW: Relate limiting factors and carrying capacity

Vocabulary Limiting factors Limiting factors Carrying capacity Carrying capacity

Limits to population Growth Limiting Factors: Limiting Factors: –A factor that causes a population growth to decrease. Competition Competition Predation Predation Parasitism & disease Parasitism & disease Drought (climate extremes) Drought (climate extremes) Human disturbances Human disturbances

Limits to Population Growth When environmental factors limit a population’s growth rate the population is said to have reached its carrying capacity. When environmental factors limit a population’s growth rate the population is said to have reached its carrying capacity. Carrying Capacity: Carrying Capacity: –The number of organisms in a population that the environment can maintain or “carry” with no increase or decrease in the population. –Birth rate = death rate

Today’s Assignment Grade I-notebooks Grade I-notebooks Lesson of the Kaibab activity Lesson of the Kaibab activity

Bell Work (period 1) What is carrying capacity? Give an example. What is carrying capacity? Give an example.

Bell Work (periods 3-5) Describe the most likely population growth curve you would expect to see in a small town made up mainly of senior citizens. Compare this growth curve to that of a small town made up of newly married couples in their twenties. Describe the most likely population growth curve you would expect to see in a small town made up mainly of senior citizens. Compare this growth curve to that of a small town made up of newly married couples in their twenties.

Week at a glance Tuesday: Tuesday: –Finish section 4.1 –Study Guide 4.1 due Wednesday: Wednesday: –Vocabulary quiz –Human population growth section 4.2 Thursday: Concept map/ review Thursday: Concept map/ review Friday: Friday: –Chapter 4 test –Parent Signatures in I-book due

Density factors and Population Growth

Today’s Objective Differentiate between density-dependent and density-independent limiting factors. Differentiate between density-dependent and density-independent limiting factors. Describe how other organisms limit population growth. Describe how other organisms limit population growth.

Key Vocabulary Density-Independent Factor Density-Independent Factor Density-Dependent Factor Density-Dependent Factor Predation Predation Competition Competition

Three patterns of dispersal are random, clumped, and uniform. Three patterns of dispersal are random, clumped, and uniform. Density factors and population growth How organisms are dispersed can be important. How organisms are dispersed can be important. Random Clumped Uniform

Section 4.1 Summary – pages Reminder: population density describes the number of individuals in a given area. Reminder: population density describes the number of individuals in a given area. Density factors and population growth There are two types of limiting factors that are related to dispersal: There are two types of limiting factors that are related to dispersal: –density-dependent –density-independent factors.

Disease, for example, can spread more quickly in a population with members that live close together. Disease, for example, can spread more quickly in a population with members that live close together. Density-dependent factors include disease, competition, predators, parasites, and food. Density-dependent factors include disease, competition, predators, parasites, and food. Density factors and population growth

Most density- independent factors are abiotic factors, such as temperature, storms, floods, drought, and major habitat disruption. Most density- independent factors are abiotic factors, such as temperature, storms, floods, drought, and major habitat disruption. Density-independent factors can affect all populations, regardless of their density. Density-independent factors can affect all populations, regardless of their density. Density factors and population growth

Organism Interactions Limit Population Size

Population sizes are limited not only by abiotic factors, but also are controlled by various interactions among organisms that share a community. Population sizes are limited not only by abiotic factors, but also are controlled by various interactions among organisms that share a community. Organism interactions that can limit population size include: Predation, Competition, Crowding, and stress Organism interactions that can limit population size include: Predation, Competition, Crowding, and stress

Predation affects population size Predation increases the chance that resources will be available for the remaining individuals in a prey population. Predation increases the chance that resources will be available for the remaining individuals in a prey population. However, when a predator consumes prey on a large enough scale, it can have a drastic effect on the size of the prey population. However, when a predator consumes prey on a large enough scale, it can have a drastic effect on the size of the prey population.

Section 4.1 Summary – pages Competition within a population Competition is a density-dependent factor. Competition is a density-dependent factor. When only a few individuals compete for resources, no problem arises. When only a few individuals compete for resources, no problem arises. When a population increases to the point at which demand for resources exceeds the supply, the population size decreases. When a population increases to the point at which demand for resources exceeds the supply, the population size decreases.

The effects of crowding and stress When populations of certain organisms become crowded, individuals may exhibit symptoms of stress. When populations of certain organisms become crowded, individuals may exhibit symptoms of stress. These symptoms include aggression, decrease in parental care, decreased fertility, and decreased resistance to disease. These symptoms include aggression, decrease in parental care, decreased fertility, and decreased resistance to disease. They symptoms then become limiting factors for growth and keep populations below carrying capacity. They symptoms then become limiting factors for growth and keep populations below carrying capacity.

Today’s assignment Period 1: Section 4.1 worksheet Period 1: Section 4.1 worksheet Periods 3, 4, & 5: Periods 3, 4, & 5: –$2.00 summary –Radio commercial activity due Thursday

Bell Work List three density-dependent factors and three density-independent factors that can limit the growth of a population. List three density-dependent factors and three density-independent factors that can limit the growth of a population.

Bell work (periods 3-5) Why might a contagious virus that causes a fatal disease be considered a density- dependent limiting factor Why might a contagious virus that causes a fatal disease be considered a density- dependent limiting factor

Population Ecology Chapter 4.2 pages Human Population

Objectives TLW: describe what could happen if the human population reaches it carrying capacity. TLW: describe what could happen if the human population reaches it carrying capacity. TLW: examine how populations of different regions of the world compare with regards to numbers and food availability. TLW: examine how populations of different regions of the world compare with regards to numbers and food availability.

Key Vocabulary Demography Demography

In the United States, a census is taken every ten years. In the United States, a census is taken every ten years. World Population One of the most useful pieces of data is the rate at which each country’s population is growing or declining. One of the most useful pieces of data is the rate at which each country’s population is growing or declining. These figures are the basis for demography, the study of human population size, density and distribution, movement, and its birth and death rates. These figures are the basis for demography, the study of human population size, density and distribution, movement, and its birth and death rates.

Human population growth is different than other organisms because humans have the ability to change their environment. Human population growth is different than other organisms because humans have the ability to change their environment. For example, man has learned to expand the carrying capacity of his environment by increasing food supply, combating pests and curing diseases. For example, man has learned to expand the carrying capacity of his environment by increasing food supply, combating pests and curing diseases. Today’s world population statistics: Today’s world population statistics: Human population growth

Question: Can the Earth support this ever increasing population?

Human population Growth Damage to the planet will eventually reduce the carrying capacity for humanity and slow the growth of the human population. Damage to the planet will eventually reduce the carrying capacity for humanity and slow the growth of the human population. What are some limiting factors for the human population? What are some limiting factors for the human population?

Ecology and growth Resources that are needed for life, such as food and water, could become scarce or contaminated. Resources that are needed for life, such as food and water, could become scarce or contaminated.

Also, the amount of waste produced by a population may become too difficult to dispose of properly. Also, the amount of waste produced by a population may become too difficult to dispose of properly. These conditions can lead to stress on current resources and contribute to the spread of diseases that affect the stability of human populations both now and to come. These conditions can lead to stress on current resources and contribute to the spread of diseases that affect the stability of human populations both now and to come. Ecology and growth

Today’s Assignment Take a stand Take a stand Food for thought Food for thought Human population graph Human population graph