Transcript Ecology

Ecology
The study of the
interactions that take
place among
organisms and their
environment
The Individual –
One organism, a single living
thing
ex: Karl the Fish
Population
 All the organisms in an
ecosystem that belong to the
same species.
 Ex. Karl and
all his friends of
the same species
What are the 3 biggest populations
in this pond community?
Name of
Population
Actual
Count
Sample
Count
Ducks
Cattails
Water Lilies
ACTUAL COUNT
• Each member of a
population is counted
one by one
Name of
Population
Actual
Count
Sample
Count
Ducks
Cattails
Water Lilies
6
20
4
Which population was
easiest to count?
Why?
RANDOM SAMPLES
•Make a GRID
•Count the total number of
squares in the grid
•Choose one square of the
grid at random.
•Count the population in that
one square.
•Estimate the total
population by multiplying the
number in one square time
the total squares in the grid.
RANDOM SAMPLES
Name of
Population
Ducks
Cattails
Water Lilies
Actual
Count
6
20
4
Sample
Count
2 x 10 = 20
3 x 10 = 30
1 x 10 = 10
ACCURACY???
Scientists help prevent over- and
under-estimation by taking
several samples and averaging
the results.
Random samples are quicker and
reduce the risk of a miscount