Biology: Testing Research Hypotheses

When a researcher has asked a question and formulated a hypothesis, he or she can test that hypothesis in a variety of different ways, including the following:

Laboratory research

  • The researcher carries out experiments and collects data that strengthen or refute the hypothesis
  • Typically, these experiments are controlled experiments, in which several trials are set up, with all variables the same among them - except for one, which is the experimental variable
  • In this way, the researcher can determine whether or not that variable has an effect on whatever outcome he or she is studying

Field research

  • Field research, compared to laboratory research, more closely mimics the “real world,” but is often more difficult to control
  • Field sites include forests, lakes, oceans, vernal pools, deserts, tundra, etc.

Analysis of collected data

  • In this case, the researcher may test the hypothesis by analyzing data that have already been collected
  • There is a great deal of epidemiological and genomic data that can be analyzed in new ways to test novel hypotheses


  • Occasionally, hypotheses are tested by doing an observational study
  • Famously, Charles Darwin used observation as one of many tools to test his theory of evolution by natural selection

Surveys and questionnaires

  • These are useful tools for gathering data about human subjects
  • They may be used by themselves, or in conjunction with other sources of data - observations, measurements, medical records, face-to-face interviews, etc.
  • Some human characteristics cannot be observed directly, and self-report forms may be the only way to obtain the data necessary to conduct research