1. Writing A Proper Hypothesis
Using the “If / Then” Method

2. What comes first, the observation or the hypothesis?
A hypothesis comes from a general observation that is made.
For example, environmentalist John Muir made a hypothesis based on the numerous observations he made of the Yosemite Valley in California.
His hypothesis was that the U-shaped valleys of Yosemite were formed from glaciers.
His hypothesis went against what most geologists believed at the time, which was that the valley was created by earthquakes.

3. “Patient observation and constant brooding above the rocks, lying upon them for years as the ice did, is the way to arrive at the truths which are graven so lavishly upon them”
–John Muir, on how he came upon his now accepted hypothesis.

4. Parts of the Statement Independent Variable:
The condition to be studied. It is controlled by the experimenter.
ex. Water
Dependent Variable:
The condition affected by the independent variable. It can’t be controlled by the experimenter.
ex. Plant Growth
Control:
The conditions that stay the same throughout the experiment. ex. Temperature of room, amount of light, etc.

5. Steps to Writing the “If” section of your Hypothesis
Start your sentence with the word “If”
Write down one of the variables (not control)
Connect statement with one of the following:
is related to
is affected by
causes
Write down the other variable

6. Writing the “Then” section of your Hypothesis
Write the word then (following the “if” section)
Make a comment on the relationship between those two variables.
Ex. If section:
If water is related to plant growth,
Ex. Then section:
then the more you water plants, the bigger they will grow.

7. Final “If / Then” Statement
If water is related to plant growth, then the more you water plants, the bigger they will grow.

8. Forming a hypothesis
On the submarine UAS Explorer, you notice large amounts of life around hydrothermal vents called “smokers” which emit heat, methane and sulfur compounds.
There is no sunlight in this deep water area.
Since you are biologists, you know that living things need to use energy from somewhere in order to be “living”.
In your groups, create 2-3 testable hypotheses you could perform based on these observations.