Background
An age-old hypothesis about robin migration says that robins arrive
in an area when the average temperature is 36°F. Is it accurate?
Why not test the hypothesis yourselves? Begin the study about a month before the robins' average arrival date in your area.
Exploration
1.
Look at the map
of average temperatures.
The lines and colored bands show places that had the same average temperatures
last week. The lines will 'migrate' across the continent as temperatures
warm in the spring. (Come back to see and print the latest map each week.)
- Find
the approximate location of your hometown. What was its average temperature
last week?
- Name
the states or regions that had a 36°F average temperature.
- Name
the states or regions you think were too cold for robins.
(Definition: The lines that connect places with the
same average temperatures are called isotherms.)
2.
Calculate and plot your average weekly temperature.
Use our Average Weekly Temperatures data
sheet and follow the example shown in the sample
graph.
3.
Watch for Robins!
Continue to calculate your average weekly temperature and
keep your eyes peeled! When your robins show up, decide whether it was before, when, or after your average weekly temperature reached 36°F.
Why
follow the average temperature line (isotherm) of 36°F?
Scientists believe that, by migrating north just behind the advance
of this isotherm, migrating birds will find food and open water available.
It also allows them to have as long a breeding season as that climate
will allow. |
|
Time:
1 period + occasional time over several weeks
Standards |
Map
of Average Temperatures
(Last week)
As
of last week, where was the average temperature 36°F?
Data
Sheet
For recording and calculating average weekly temperatures
Sample
Graph
of average weekly temperatures |