Corian Thomas Taylor Kirsten Mr. LY’s desk Promethean Board Carolann James Joekey- dia Korey Melvin Johnny Byron Torre Dominique Briana Kierra JonathanKrystal-

Corian

Thomas

Taylor

Kirsten

Mr. LY’s desk

Promethean Board

Carolann

James

Joekey-dia

KoreyMelvi

nJohnnyByron

Torre

Dominique

Briana

KierraJonath

anKrystal-yn

Darnell

Keiana

Chanc

Aaron

Maria

Lashante

Patrick

Aron CierraBlue Caira

Branden

Terrance

Door into classL R

Carrying Capacity

Catalyst Humans cut down 2.4 acres of

rainforest (about the size of two football fields) EVERY SECOND. We estimate that 137 species go extinct every day as a result. How does deforestation affect biodiversity?Are rainforest ecosystems more or less

stable due to deforestation?How might the biodiversity in these

rainforests benefit humans?

Objectives

By the end of today, all SWBAT…

Ace the quiz!Predict if population size will increase or decrease based upon limiting factors and carrying capacity

Agenda

Catalyst review Quiz How many in a population? Analyzing graphs Jeopardy! Closing Exit Question

Catalyst Review

Humans cut down 2.4 acres of rainforest (about the size of two football fields) EVERY SECOND. We estimate that 137 species go extinct every day as a result. How does deforestation affect biodiversity? Are rainforest ecosystems more or less

stable due to deforestation? How might the biodiversity in these rainforests

benefit humans?

Quiz!

Put away your binders… Turn your desks into rows…

And let’s ace that quiz!

You have 15 minutes

How Many?

We’ve been talking about populations of organisms increasing or decreasing in size… When new predators come When organisms leave the food web

But what controls how many organisms exist in a population in the first place?

What determines population? Why can’t we have…1,000,000 students

here at L.W. Higgins? Space Teachers Supplies Student Behavior These

resources are our limiting

factors

Key Point #1: An environment can only support as many organisms as there is available food, water, and free space Carrying capacity = maximum number of

organisms that can live somewhere, based on the food, water, and free space there

Every species has a different carrying capacity.

Food, water, and free space are the LIMITING FACTORS that determine carrying capacity

Carrying Capacity

Your fridge is like all of the resources (food, water, free space) in an ecosystem.

What if we want to throw a party?

Imagine Your Fridge

We can keep inviting people, as long as there’s enough food in the fridge.But with each new guest, there’s less to go around.

Imagine Your Fridge

The fridge won’t replenish magically, and I don’t have the money to keep putting food in the fridge forever.

So too many guests means that…So too many animals means that…

Someone goes hungry… Not enough food/water/free space…

And leaves the party. And organisms die.

Imagine Your Fridge

Carrying Capacity

Key Point #2: We can read a carrying capacity graph to predict changes in population size

Time

Po

pu

latio

n s

ize

A B

C

D

Carrying Capacity

When a population is BELOW its carrying capacity, it will INCREASE in size

Birth rate exceeds death rates

Time

Po

pu

latio

n s

ize

A B

C

D

Carrying Capacity

But if it increases too much and rises ABOVE its carrying capacity, it will DECREASE in size

Death rate exceeds birth rate

Time

Po

pu

latio

n s

ize

A B

C

D

Carrying Capacity

This happens over and over… but the increases and decreases get smaller and smaller…

Time

Po

pu

latio

n s

ize

A B

C

D

Carrying Capacity

Until eventually, the population size BECOMES STABLE AT THE CARRYING CAPACITY

Birth rate = death rate

Time

Po

pu

latio

n s

ize

A B

C

D

determined by

such asabove it

WORD BANK: water, carrying capacity, pop. size increases, limiting factors, food, pop. size decreases, space

below it

Jeopardy!

Rules:1. Groups will be pulled at random to

select questions from Jeopardy board2. All groups will answer all questions3. All groups will get 50 points for a

correct answer, and the group that selected the answer will get ALL points

Closing

An environment can only support as many organisms as there is available food, water, and free space Carrying capacity = maximum number of

organisms that can live somewhere based on these limiting factors

We can read a carrying capacity graph to predict changes in population size Below carrying capacity = increase Above carrying capacity = decease Over time, population stabilizes at carrying

capacity

Exit Questions

What is the carrying capacity of rabbits in this ecosystem?

When is the carrying capacity for rabbits first reached?

Why does rabbit population size increase in the highlighted section of the graph?