Scientific Inquiry and Foundations for BIO 201 — Lecture Notes
Overview: science as an iterative process of inquiry
- Science is a process of inquiry: observe, question, and try to understand the natural world through repeated cycles.
- Inquiry can operate with or without a predefined hypothesis. In some natural sciences (e.g., oceanographic cruises, long-term monitoring stations), researchers collect large amounts of data first and look for patterns before forming hypotheses.
- The overarching structure is iterative, not a strictly linear path:
- Observation → Question → Hypothesis/Prediction → Test → Evaluate data → Decide if the hypothesis is supported or rejected, not proven.
- Real science often loops back: new observations may lead to new hypotheses, or additional factors must be controlled or considered.
- Practical implication: this framework helps frame foundational biology (BIO 201) and builds toward the ability to generate testable hypotheses from observations.
The iterative nature of the Scientific Method
- General structure (not strictly linear):
- Observation
- Question
- Hypothesis or tentative educated guess
- Prediction (if the hypothesis is true, then this should happen)
- Test/Experiment
- Evaluate data
- Support or reject the hypothesis (never absolutely prove) → may lead to refinement or new hypotheses.
- When testing, control for one variable at a time to avoid confounding factors.
- Even simple demonstrations (e.g., a desk lamp) illustrate multiple explanations and the need for controlled testing.
Example: Desk lamp scenario illustrating hypothesis testing
- Observation: the desk lamp does not turn on.
- Question: why is the lamp not working?
- Possible hypotheses:
- H1: the bulb is burned out.
- H2: the bulb is not screwed in properly.
- Prediction for each hypothesis:
- If H1 is true, then replacing the bulb should fix the lamp.
- If H2 is true, then screwing the bulb in should fix the lamp.
- Test: replace the bulb and observe whether the lamp works.
- Interpretation:
- Replacing the bulb may make the lamp work, but this does not prove which specific fault existed; there could be other factors (e.g., power surge, wiring issue).
- The conclusion is: the hypothesis is supported by the data, not definitively proven.
- Important nuance:
- If the power to the building surges or drops, the lamp can appear to be fixed by bulb replacement even if the underlying issue wasn’t the bulb.
- This illustrates that a single data point or test cannot establish absolute truth; more data and controlled testing are needed.
Key concepts: hypotheses, predictions, and control
- Hypothesis: a tentative, educated guess that can be tested via experimentation.
- Prediction: a logical consequence of a hypothesis (a statement that can be tested).
- Control group: a baseline or standard against which results are compared.
- Control of variables: test one variable at a time to isolate its effect.
- When experiments generate substantial evidence across many observations, a hypothesis may contribute to building a theory.
Deductive vs Inductive reasoning in science
- Deductive reasoning (general → specific):
- Start with a general principle and derive specific conclusions.
- Example: If the sun always rises in the East (general principle) and you observe the sun in the East, you infer it is morning (specific conclusion).
- Formalized idea: G
ightarrow S where G is a general principle and S is a specific outcome.
- Inductive reasoning (specific → general):
- Start with many specific observations and generalize to a broader principle.
- Example: Observing the sun rising in the East on many days leads to the general statement that the sun rises in the East.
- Formalized idea: from multiple observations S1, S2,
ots
, S_n
ightarrow G where G is a general principle.
- The point: scientists use both directions of reasoning to make sense of data and to generate/test theories.
The role of facts, hypotheses, and theories in learning biology
- The course emphasizes not just memorizing facts but developing a framework to form hypotheses when presented with observations.
- By the end of the semester, students should be able to form plausible hypotheses about novel cell observations based on foundational knowledge.
- Hypotheses vs Theory:
- Hypothesis: a testable statement that guides experiments.
- Theory: a well-supported, broad explanation backed by a large body of evidence from many experiments and researchers.
- Examples of theories (conceptual sense): the theory of relativity, the theory of evolution.
- A hypothesis may be supported by many observations; as evidence accumulates, it may contribute to a theory.
- Important distinction: a theory is not a guess; it is a robust, extensively tested framework.
Why does this matter for scientific thinking in BIO 201?
- The purpose of learning these processes is to enable flexible thinking when examining cells and biological phenomena.
- When you see an unusual cell, a solid foundation allows you to generate a plausible hypothesis (e.g., about the cytoskeleton or cell division) and design experiments to gather more information.
- Case study practice helps you apply general principles to specific observations, bridging theory and experiment.
- You will learn to avoid overclaiming from a single observation, instead building a coherent set of evidence to support or reject a hypothesis.
The terminology and progression from hypothesis to theory in practice
- Hypothesis: tentative explanation tested by experiments and observations.
- When many independent lines of evidence converge, a hypothesis can become a theory.
- Theories are not proven in an absolute sense; they are supported by cumulative data.
- Theories may be refined or extended as new data emerge.
Limitations of science: scope, ethics, and practicality
- Science has limits and cannot answer every kind of question:
- Not all questions are empirical or testable; some relate to values, beliefs, or morality.
- Some questions are philosophical or theological and extend beyond the scope of testable hypotheses.
- Some questions may be unanswerable with current tools or knowledge.
- Potential biases and limitations:
- Scientists bring biases and blind spots; replication and collaboration across diverse groups help mitigate this.
- Bias can affect interpretation and reporting; multiple studies and independent verification improve reliability.
- Practical and ethical constraints:
- Some experiments may raise ethical concerns or require prohibitive resources; not all hypotheticals can be tested.
- Science does not provide direct answers about how to use technology; ethical and societal considerations require human input and discourse.
- Precision and measurement limits:
- Some questions require extremely precise measurements; advances in technology improve capabilities but do not guarantee absolute certainty.
- Mechanistic explanations vs. ultimate why:
- Science often addresses mechanism (how things work) rather than ultimate purpose or why they exist.
- Some questions may lie outside empirical testing (e.g., supernatural explanations or belief-based questions).
- The social nature of science:
- Science is a collective enterprise, best advanced by diverse researchers and institutions to approach a closer approximation of reality.
- Reproducibility, peer review, and transparent methods are essential for building credible knowledge.
Connecting to real-world science and classroom practice
- This framework helps students engage with real-world problems by forming testable hypotheses from observations and designing controlled experiments.
- Case studies and exercises in BIO 201 will reinforce the practice of hypothesis generation, controlled testing, and interpretation of results.
- The ultimate goal is to empower students to think critically, reason rigorously, and communicate findings effectively, even when data are imperfect or ambiguous.
Preview: next week
- The course will delve into the biology of cells, applying these scientific reasoning skills to understanding cell structure and function.
- Expect to practice identifying hypotheses from observations, designing experiments, and evaluating evidence in the context of cellular biology.