Famous Examples of the Scientific Method in Ecology Introduction
The scientific method is not a new idea; it has been utilized by generations of scientists. This activity will
introduce you to some of the most famous scientific experiments and discoveries - ones that continue to
influence our lives even today! See if you can identify the different parts of the scientific method and
experimental design in each.
The F. A.C. E. Method
As botanists and ecologists became increasingly aware of the increase in atmospheric carbon dioxide due
to humans burning fossil fuels, they began to wonder if this change could affect plant growth. The Free-
air Carbon dioxide Enrichment (F. A.C. E.) method was designed to test this.
The method uses a series of pipes to regularly release small amounts of carbon dioxide into an enclosed
area where a crop such as rice or wheat was growing. Scientists would record the yield of each crop after
an entire growing season and compare it to another plot where the plants were exposed to normal air.
Each plot of growing area received the same amount of sunlight, fertilizer, and water.
Overall, scientists measured a 5-8% increase in yield in the CO2-enriched plots compared to the other
ones.
1. What independent variable were the scientists studying in this case? What dependent variable
were the scientists measuring?
Independent variable - The additional CO2
Dependent variable - The yield of the crops tested
Trees
FACE
Ring
2. What was the experimental group in their
study? What was the control group?
The experimental group received the additional
CO2. The control group
Parameter
sensor
3. When an experiment is designed, all variables
between the experimental group and control
group must be held constant. What were the
constant variables in these experiments?