Basic carrying capacity presentation, with key definitions and examples. Data are always changing on carrying capacity estimates. This uses data that is about 8 years old, but it is useful if you explain this to your students from the start.

1. Carrying Capacity
"The maximum number of individuals of a"The maximum number of individuals of a
given species that can be supported….given species that can be supported….
on a sustainable basis. "on a sustainable basis. "

2. In population ecology….
….. the carrying capacity is the
population size at which the population
growth rate equals zero.

3. What is the Carrying Capacity of Earth
2 billion or 40 billion?
Some scientists say 2 billion others say 40 billion!
When scientists say that the carrying capacity of the
Earth is 2 billion, the scientists know we have 6.9
billion already…. So what’s up???

4. What the scientistsWhat the scientists
are really sayingare really saying
is, that…..is, that…..
…….if you add up all the supplies in the world,.if you add up all the supplies in the world,
and divide them up according to the amountand divide them up according to the amount
that a typical American uses,that a typical American uses,
then there is only enough for 2 billion peoplethen there is only enough for 2 billion people..

5. We have almost 7 billion people…!
… so the amount of fuel, water, electricity, etc.
is just not enough to go around.
Some people are left out.
We know this is the case because, only about
1.2 billion people live in higher developed
countries while the other 4.8 billion people
have to make do with less.

6. When some scientists say the carrying capacity
of Earth is 40 billion, they are saying that…
….IF the richer people give up all their luxuries
such as cars, electricity, education, clean
water, meat etc.
That would allow us to provide minimum
amounts of supplies to a much larger number
of people.

7. In fact, scientists sayIn fact, scientists say,,
we could provide minimum supplies towe could provide minimum supplies to
40 billion people40 billion people
IFIF no oneno one lived a luxury modern life stylelived a luxury modern life style
like the average Americans of 2001like the average Americans of 2001.