Unit B

Module 4 ~ Lesson 2

 Developing a Theory to Explain Change

Science attempts to explain the natural world through observation and testing. The development of scientific laws and theories begin with a hypothesis. A hypothesis is a possible explanation to a question based on fact and observation. When a hypothesis is tested over and over with consistent results, scientists are able to develop a scientific theory that allows them to make successful predictions and explanations about the natural world. A scientific law is also developed from repeated testing of a hypothesis. A law is better at predicting an outcome but does not attempt to explain the mechanism that led to that outcome. Laws and theories are important in the development of scientific knowledge, even if they are wrong.

Evolutionary scientists, such as Charles Darwin and Jean Baptiste Lamarck, used their observations to explain the phenomenon of evolution. 

In this lesson you will explore the following essential questions:

  • How do theories explaining evolutionary change compare?
  • What theories attempt to explain the pace of evolutionary change?