To rate this resource, click a star:
Students explore the molecular basis and evolutionary origin of trichromatic (red/green/blue) color vision in humans and our close evolutionary relatives using nucleic acid sequences of opsins, key proteins involved in the process.
DNA to Darwin
This lesson would be appropriate for an upper level genetics class as is, but could be modified to suit an introductory freshman-level course. Use this resource to relate evolutionary concepts to the topic of animal sensory systems (or get more suggestions for incorporating evolution throughout your biology syllabus). Be sure to test the free software used in this lab before attempting it with students. Some users have reported trouble, while others have had none.
Correspondence to the Next Generation Science Standards is indicated in parentheses after each relevant concept. See our conceptual framework for details.
- Biological evolution accounts for diversity over long periods of time.
- Present-day species evolved from earlier species; the relatedness of organisms is the result of common ancestry.
- There is a fit between organisms and their environments, though not always a perfect fit.
- An organism's features reflect its evolutionary history.
- Similarities among existing organisms (including morphological, developmental, and molecular similarities) reflect common ancestry and provide evidence for evolution.
- Features sometimes acquire new functions through natural selection.
- Not all similar traits are homologous; some are the result of convergent evolution.
- New heritable traits can result from mutations.
- Traits that confer an advantage may persist in the population and are called adaptations.
- Scientists can test ideas about events and processes long past, very distant, and not directly observable.
- Scientists use multiple lines of evidence (including morphological, developmental, and molecular evidence) to infer the relatedness of taxa.
- Evolutionary trees (i.e., phylogenies or cladograms) portray hypotheses about evolutionary relationships.
- Evolutionary trees can be used to make inferences and predictions.