Students build and evolve and modify paper-and-straw “birds” to simulate natural selection acting on random mutations.
Three to four class periods.
Correspondence to the Next Generation Science Standards is indicated in parentheses after each relevant concept. See our conceptual framework for details.
- There is a fit between organisms and their environments, though not always a perfect fit. (LS4.C)
- An organism’s features reflect its evolutionary history.
- Evolution results from selection acting upon genetic variation within a population. (LS4.B)
- Mutations are random.
- Traits that confer an advantage may persist in the population and are called adaptations. (LS4.B, LS4.C)
- Inherited characteristics affect the likelihood of an organism's survival and reproduction. (LS4.B, LS4.C)
- Depending on environmental conditions, inherited characteristics may be advantageous, neutral, or detrimental.
- Random factors can affect the survival of individuals and of populations.
- Natural selection acts on the variation that exists in a population. (LS4.B, LS4.C)
- Organisms cannot intentionally produce adaptive mutations in response to environmental influences.
- Over time, the proportion of individuals with advantageous characteristics may increase (and the proportion with disadvantageous characteristics may decrease) due to their likelihood of surviving and reproducing. (LS4.B, LS4.C)
- Speciation is the splitting of one ancestral lineage into two or more descendent lineages.