BIOL 105 Chapter 1 - Process of Science

Chapter 1: Process of Science

What is Science?

• Definition: Science is a method to seek answers, a process using observations and experiments to draw evidence-based conclusions, and a way of knowing.

Types of Evidence

Anecdotal Evidence

• Derived from personal observation and experience.

• Lacks systematic testing.

• Conclusions based on personal experiences and often informally vetted.

• Frequently shared on social media.

• Can feel correct and persuasive but is unreliable.

• May inspire questions for scientific studies.

Scientific Evidence

• Based on systematic observation and experimentation.

• Involves testable and falsifiable hypotheses.

• Thousands of data points considered and statistically analyzed.

• Conclusions formally vetted through peer-review and published in scientific journals.

The Scientific Process

Step 1: Make an Observation

• Start with informal observations, which may be unreliable and anecdotal.

Step 2: Formulate a Question

• Use observations to devise a scientific question.

• Example: "Do cell phones cause cancer?"

Step 3: Study Previous Research

• Read relevant literature to understand current information.

• Peer Review: Review by experts before publication to ensure proper design and interpretation, thus improving research quality.

Step 4: Formulate a Scientific Hypothesis

• Create a testable and falsifiable hypothesis based on gathered information.

  • Example: "Exposure to cell phone radiation increases the incidence of cancer."

• A hypothesis must be testable and can be ruled out by new data.

Characteristics of Scientific Hypotheses

• A hypothesis that cannot be tested is not considered scientific.

• Hypotheses can never be definitively proven; they are accepted until disproven by further testing.

Experimentation

Step 5: Conduct Experiments

• Experiment: A carefully designed test to support or rule out hypotheses.

• Experimental and Control Groups:

  • Experimental Group: Receives the treatment or manipulation.

  • Control Group: Experiences no manipulation, providing a basis for comparison.

Key Experimental Concepts

• Independent Variable: The factor deliberately changed in the experiment.

• Placebo: A fake treatment used in the control group to mimic the experimental experience.

• Dependent Variable: The measured result analyzed from both groups.

Drawing Conclusions

Importance of Repetition

• More repetitions by different scientists increase confidence in conclusions drawn.

Sample Size's Role

• Larger sample sizes enhance the statistical significance, indicating results are likely real rather than due to chance.

Scientific Theory vs. Everyday Use of "Theory"

• In daily life, "theory" is an idea explaining events.

• In science, it refers to a hypothesis supported after rigorous testing.

• Hypotheses that withstand testing may evolve into scientific theories.

Publication of Results

• Experimental results are published in peer-reviewed journals to ensure scientific credibility.

Finding Patterns in Observation

• Some questions cannot be tested purely through experiments.

• Observing patterns in nature can lead to potential answers.

• Correlation: A consistent relationship between two variables does not imply causation.

Example Inquiry

• Question: Is there a relationship between wireless phone use and brain cancer incidence?

• Observation: Increased wireless usage has not coincided with a brain cancer epidemic, but this doesn't dismiss a potential relationship.

Summary of the Scientific Method

• Science is a quest for answers via observations and experiments.

• Hypotheses are potential answers tested through controlled experiments or observational studies.

Factors Influencing Scientific Conclusions

• Peer review ensures validity and accuracy of scientific results.

• Experimental controls distinguish tested variables from others.

• The strength of conclusions may vary with type of study and sample size.