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How Are Monarch Colonies Measured?
Thinking About Scientific Methods
Imagine
the Scientist's Job!
It's a daunting task to estimate the size of the monarch's winter colonies!
But it's important to know the size of the monarch population, so scientists
have developed a method for estimating it. It is NOT EASY, as you are
about to see. In real life, the butterflies, the forest, the weather,
and even the scientists are constantly changing!
Try
This! Count Butterfly Trees |
Before
we look at the scientists' methods, walk into
a sanctuary, take a look, and try it yourself.
- Look
at the photo to the right. The orange you see in certain trees
are monarch butterflies!
- Draw
or imagine a "perimeter" line around what you think
is the monarch colony. (This is what scientists do so they can
estimate the colony size.)
- How
many butterfly trees do you count within the colony area?
- As
you work, record the challenges you notice, the questions you
have, and the decisions you make to reach your final count.
- When
you're done, see how
we looked at the problem.
|
Then
Look at the Scientists' Methods |
Are
you ready now to see how the scientists work? Read the description
of the steps they take. Can you name at least one factor (variable)
they try to keep the same (control) each time they measure?
Mexican
Scientist Eduardo Rendon |
|
Now
Try to Identify Variables |
Pictures
and Descriptions Hold Clues...
Look at the pictures and information at the link below. Keep your
tree-counting experience and the scientists' methods in mind. Use
the worksheet to record the variables you identify that are hard
or impossible to have control over. How might each variable affect
the accuracy of the results?
Once
you've filled in the worksheet, see
our list. |
|
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