Evolution, Entropy, & Biological Information

A logical question to be expected from students: "How could life develop, that is, change, evolve from simple, primitive organisms into the complex forms existing today, while at the same time there is a generally observed decline and disorganization - the second law of thermodynamics?" The explanations in biology textbooks relied upon by students and instructors are incomplete. A necessary but insufficient premise is that only total entropy of a system must increase. In this article, I present background information for a lesson plan on entropy and question biology textbook presentations on the second law and how life could evolve despite it. The principal concept is that biological information in macromolecules provides fresh insight into evolution in the earth's thermodynamic system.