Skip to content
Marlbridge

AP® Biology · Unit 7 · Topic 7.1

Introduction to Natural Selection: Topic Checklist (Biology 7.1)

Specific “I can…” statements for Darwin's argument, fitness and changing selection, each linked to the guide section and practice question that shows whether you can really do it.

Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.

Understanding

  • I can define evolution in terms of heritable change in a population over generations, and explain why individuals do not evolve. (Guide: “What evolution is”; Practice Q5)
  • I can state that natural selection is a major mechanism of evolution, and name another kind of process that also changes populations. (Guide: “What evolution is”)
  • I can set out Darwin’s argument in order: overproduction, competition for limited resources, variation, inheritance, differential survival and reproduction. (Guide: “Darwin’s argument, step by step”; Practice Q1, Q5)
  • I can explain why fitness is measured by reproductive success and not by strength or lifespan. (Guide: “Fitness means reproductive success”; Practice Q2)
  • I can give examples of biotic and abiotic factors and explain how a change in them can reverse the direction of selection. (Guide: “Changing environments change the direction of selection”; Practice Q4)

Calculation and skills

  • I can calculate mean offspring per individual and relative fitness for each phenotype. (Guide: Worked example 1; Practice Q3, Q6)
  • I can project the fraction of a phenotype in the next generation, and state the assumptions behind the projection. (Guide: Worked example 1; Practice Q6, Q7)
  • I can calculate percentage survival and a mean from a frequency table. (Guide: Worked example 2)
  • I can describe a flowchart, histogram or line graph by naming its axes, groups, units and trend. (Guide: Figure 1, Worked example 2; Practice Q4)

Reasoning

  • I can evaluate a claim that confuses survival with fitness, using data. (Guide: Worked example 1; Practice Q6)
  • I can explain why a difference in survival between two groups is not enough on its own to show that a trait will spread. (Guide: Worked example 2; Practice Q4)
  • I can explain how the size of a fitness difference affects the rate of change, and how a changing environment affects its direction. (Practice Q7)

All ticked? Move on to Topic 7.2, Natural Selection, or return to the course roadmap.

AP® and Advanced Placement® are trademarks registered by the College Board, which is not affiliated with, and does not endorse, this website. Marlbridge is an independent tuition provider. It is not an authorized AP course provider, an AP school or an exam centre, and these resources are not official College Board materials. Reading them or doing simulations does not meet the laboratory requirement of an AP science course.