Active learning ideas
Natural selection is the primary mechanism of evolution. This topic explores how variation, selection pressures, and differential reproductive success lead to adaptation. Students study examples like antibiotic resistance and the peppered moth to see evolution in action. In the JC2 syllabus, the focus is on the population as the unit of evolution, not the individual.
Activity 01
Students use different 'beaks' (spoons, tweezers, clips) to collect 'food' (seeds, beads). Over several 'generations', they track which beak types survive and reproduce, calculating the change in 'population' traits.
How do DNA and protein sequences reveal evolutionary relationships?
Activity 02
Groups analyze real-world data from local hospitals showing the rise of resistant bacteria over a decade. They must identify the selection pressure and explain the genetic basis for the shift.
What are the principles of constructing a phylogenetic tree?
Activity 03
If we 'replayed the tape of life', would we get the same results? Students debate the roles of random mutation versus deterministic selection pressures in shaping life.
How do molecular clocks estimate divergence times?
Templates
Drop them into your lesson, edit them, and print or share.
A few notes on teaching this unit
Watch Out for These Misconceptions
Individuals evolve to 'fit' their environment.
Individuals are born with certain traits; they don't change them. Evolution is a change in the population's gene pool over generations. Using a 'before and after' population tally helps students see the shift.
Natural selection is a 'random' process.
While mutations are random, selection is highly non-random, it favors traits that provide a survival advantage. A simulation where 'random' traits meet 'specific' environmental hurdles helps clarify this.
Methods used in this brief
Population Dynamics and Hardy-Weinberg Extensions
Apply mathematical models to study allele frequency changes in populations. Investigate the effects of genetic drift, gene flow, and non-random mating.
8 methodologies
Speciation and Macroevolution
Explore the mechanisms of allopatric and sympatric speciation. Discuss the evidence for major evolutionary transitions in the fossil record.
8 methodologies