Lesson summary for...

Evo in the news: Got lactase?

Author/Source: UC Museum of Paleontology
Overview:The ability to digest milk is a recent evolutionary innovation that has spread through some human populations. This news brief from April 2007 describes how evolution has allowed different human populations to take advantage of the nutritional possibilities of dairying.
Concepts:This lesson covers the following concepts:
  • There is a fit between organisms and their environments, though not always a perfect fit.
  • All organisms, including humans, retain evidence of their evolutionary history.
  • The fossil record provides evidence for evolution.
  • There are similarities and differences among fossils and living organisms.
  • Mutations are random, but selection is not; selection is dependent on many factors.
  • Traits that are advantageous often persist in a population.
  • Inherited characteristics affect the likelihood of an organism's survival and reproduction.
  • Depending on environmental conditions, inherited characteristics may be advantageous, neutral, or detrimental.
  • The story of the evolution of living things is always being refined as we gather more evidence.
  • Our understanding of life through time is based upon multiple lines of evidence.
  • Scientists use fossils (including sequences of fossils showing gradual change over time) to learn about past life.
Grade Level:9-12
Time:20 minutes
Teacher Background:Explore these links for additional information on the topics covered in this lesson:
Teaching Tips:This article includes a set of discussion and extension questions for use in class, as well as a sidebar that would be appropriate for AP students. It also includes hints about related lessons that might be used in conjunction with this one. This example could be easily integrated into instruction on Mendelian genetics, since lactose tolerance is inherited as a dominant Mendelian trait.