BIOL 2060 - Tutorial Notes
Pre-Tutorial 1 - The Scientific Method
● Steps of the scientific method:
○ 1) Make an observation
■ Patterns that are observed in nature between two or more variables
○ 2) Formulate a hypothesis
■ Y (dependent variable) is related to X (independent variable) because of a
mechanism (why or how the relationship exists)
○ 3) Generate predictions
■ If your hypothesis was supported, what result would you expect?
○ 4) Design an experiment
■ Components of an experiment include:
● Experimental unit(s)
○ The thing you apply the treatment to
● Treatment
○ The experimental manipulation
● Control
○ Baseline
● Replication
○ How many experimental units you apply each treatment to
○ Keep the rule of 10 in mind
● Randomization
○ Used to assign treatments to experimental units without bias
○ Can use a random number generator
● Response variable
○ The thing you are measuring
○ 5) Collect and analyze data
■ Data is analyzed with statistical tests
● You want a 95% level of confidence (p < 0.05)
■ How to estimate the 95% confidence interval (CI)
● Calculate the mean and standard error (SE) for the control and
treatment
● Estimate 95% CI by multiplying SE by 2
● Plot the mean +/- 95% CI
○ If error bars do not overlap, there is a significant difference
between the control and treatment
○ 6) Compare predictions and data
○ 7) Accept or reject hypothesis
■ When the prediction is upheld, the hypothesis is supported
● Primary Journal Article:
○ How scientists present their inquiries
○ Have the IMRAD format:
■ Abstract: concise description of the purpose, methods, results, and conclusions
■ Introduction: background information, relevance (why does this study matter?),
purpose, hypothesis, and predictions
■ Methods: how was the study designed, why were those design choices made
(justification), and how were the results analyzed?
■ Results: presents results as text, figures, and tables. What were the main
, findings? Figures display trends
■ And
■ Discussion: what conclusions were drawn from the data, how do they compare
to other studies, and what are the next steps in this research?
● Tips For Interpreting Graphs:
○ Understand the axes and units
○ Evaluate the scale of the axes
■ Minimum and maximum values on the x- and y-axis
■ Does each scale begin at zero?
■ Is there a break in the scale indicating that some of the values are unnecessary
and have been deleted?
■ Normal linear, or logarithmic scale?
○ Amounts of variation in the results?
■ Are data points clustered around the mean or more spread out?
○ Look for statistically significant differences in the results
■ Statistical significance can be denoted by asterisks
● * = p < 0.05
● ** = p < 0.01
● *** = p < 0.001
○ Asses the direction, slope, and shape of the relationship
■ Look for positive (an increase in one variable, increases the other variable) and
negative (an increase in on variable, decreases the other variable) relationships
■ Slope indicates the strength of the relationship
■ Shape of the curve can be subjective and may require statistical tests to
determine
○ Examine the figure caption to ensure it’s specific and complete
Pre-Tutorial 2 - Writing a Research Question
● Components of a Research Question:
○ The invasive species
■ Include latin and common names
■ Identify the native species that is interacting with the invasive one
■ Be specific as to which species is invasive
○ The geographic location
■ The location must be as specific as possible
○ The ecological question you will investigate
■ Should be:
● Clear and concise
● Specific and testable
● Compelling and novel
■ Must relate to the ecology of biological invasions in Canada
■ Cannot be focused on management, economics, policy, or any other non-
ecological topic
● Simberloff et. al 2013:
○ Biological invasions are a pervasive global change challenging the conservation of
biodiversity and nature resources
○ The full range of ecological, economic, and sociological consequences should be
considered when an invasion impact is evaluated
Pre-Tutorial 1 - The Scientific Method
● Steps of the scientific method:
○ 1) Make an observation
■ Patterns that are observed in nature between two or more variables
○ 2) Formulate a hypothesis
■ Y (dependent variable) is related to X (independent variable) because of a
mechanism (why or how the relationship exists)
○ 3) Generate predictions
■ If your hypothesis was supported, what result would you expect?
○ 4) Design an experiment
■ Components of an experiment include:
● Experimental unit(s)
○ The thing you apply the treatment to
● Treatment
○ The experimental manipulation
● Control
○ Baseline
● Replication
○ How many experimental units you apply each treatment to
○ Keep the rule of 10 in mind
● Randomization
○ Used to assign treatments to experimental units without bias
○ Can use a random number generator
● Response variable
○ The thing you are measuring
○ 5) Collect and analyze data
■ Data is analyzed with statistical tests
● You want a 95% level of confidence (p < 0.05)
■ How to estimate the 95% confidence interval (CI)
● Calculate the mean and standard error (SE) for the control and
treatment
● Estimate 95% CI by multiplying SE by 2
● Plot the mean +/- 95% CI
○ If error bars do not overlap, there is a significant difference
between the control and treatment
○ 6) Compare predictions and data
○ 7) Accept or reject hypothesis
■ When the prediction is upheld, the hypothesis is supported
● Primary Journal Article:
○ How scientists present their inquiries
○ Have the IMRAD format:
■ Abstract: concise description of the purpose, methods, results, and conclusions
■ Introduction: background information, relevance (why does this study matter?),
purpose, hypothesis, and predictions
■ Methods: how was the study designed, why were those design choices made
(justification), and how were the results analyzed?
■ Results: presents results as text, figures, and tables. What were the main
, findings? Figures display trends
■ And
■ Discussion: what conclusions were drawn from the data, how do they compare
to other studies, and what are the next steps in this research?
● Tips For Interpreting Graphs:
○ Understand the axes and units
○ Evaluate the scale of the axes
■ Minimum and maximum values on the x- and y-axis
■ Does each scale begin at zero?
■ Is there a break in the scale indicating that some of the values are unnecessary
and have been deleted?
■ Normal linear, or logarithmic scale?
○ Amounts of variation in the results?
■ Are data points clustered around the mean or more spread out?
○ Look for statistically significant differences in the results
■ Statistical significance can be denoted by asterisks
● * = p < 0.05
● ** = p < 0.01
● *** = p < 0.001
○ Asses the direction, slope, and shape of the relationship
■ Look for positive (an increase in one variable, increases the other variable) and
negative (an increase in on variable, decreases the other variable) relationships
■ Slope indicates the strength of the relationship
■ Shape of the curve can be subjective and may require statistical tests to
determine
○ Examine the figure caption to ensure it’s specific and complete
Pre-Tutorial 2 - Writing a Research Question
● Components of a Research Question:
○ The invasive species
■ Include latin and common names
■ Identify the native species that is interacting with the invasive one
■ Be specific as to which species is invasive
○ The geographic location
■ The location must be as specific as possible
○ The ecological question you will investigate
■ Should be:
● Clear and concise
● Specific and testable
● Compelling and novel
■ Must relate to the ecology of biological invasions in Canada
■ Cannot be focused on management, economics, policy, or any other non-
ecological topic
● Simberloff et. al 2013:
○ Biological invasions are a pervasive global change challenging the conservation of
biodiversity and nature resources
○ The full range of ecological, economic, and sociological consequences should be
considered when an invasion impact is evaluated