Testing human variation
This experiment is meant to show us the normal variation which exists in us and in almost all living things. This normal or Gaussian distribution is a very important feature of science which can be shown with almost any different group of people/plants etc. It also helps scientists and doctors decide what should be considered normal and what is very different from normal.
You will need:
For the volcano shape:
- A class full of students
- A large white board (this can be made by taping many sheets of white paper together against a board.)
- A ruler or better still a height chart
- A heart rate monitor from some fitness equipment or from a home blood pressure monitoring device.
And last but not least ... a helping hand from an adult.
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Method
Ask all the students in a class to line up next to each other, just in front of the white board with the tallest at one end of the line and the shortest at the other.
Ask an adult to draw a line over your heads to show the range of heights.
Now rearrange the students with the tallest at the centre and the shorter ones at the sides.
Again ask the adult to draw another line showing this pattern.
None of these patterns really mean as much scientifically as the one we are going to do next.
Now each student should line up against the height chart and the adult together with another student can measure his/her height. The student in charge can now make a dot on the wall ( in columns) for every person at that height. (Heights can be grouped in groups of 2 or 5 cm depending on the variation in the class).
This graph now shows the normal or Gaussian distribution of heights. It shows that many people are of a middle height and a few people have a higher or lesser height than the common middle height. This can now be used to demonstrate the median as well as the mode and the mean ( the latter by calculation). The principle of standard deviations from the mean can also be shown and the bulk of students can be shown to lie within +/- 2 standard deviations from the mean.
Now the heart rate monitor is used to detect heart rate and students are lined up with those with the greatest heart rate at one end of the line and those with the slowest heart rate at the other end.
The student in charge now can draw a line over their heads - indicating their height.
Does it seem that heart rate and height are related at all?