CurriculumGrade 9Science

Four Factors of Evolution

Aligned to HS-LS4-2 — Next Generation Science Standards.

What this lesson teaches

Evolution by natural selection follows from four factors: organisms overproduce offspring, inherited traits vary, resources are limited, and individuals with helpful traits survive and reproduce more.

Worked example

Finches hatch more chicks than an island can feed; those with beaks suited to the available seeds survive, breed, and pass on that beak shape more often than the rest.

Practice questions

  1. List the four factors that together drive natural selection.
  2. Show how limited food combined with trait variation leads to different survival rates.
  3. Construct an explanation for how these four factors change a population's traits over generations.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

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En español

Cuatro factores de la evolución

La evolución por selección natural se deriva de cuatro factores: los organismos producen más descendencia de la que sobrevive, los rasgos heredados varían, los recursos son limitados y los individuos con rasgos ventajosos sobreviven y se reproducen más.

Ejemplo: Los pinzones incuban más polluelos de los que una isla puede alimentar; los que tienen picos adecuados para las semillas disponibles sobreviven, se reproducen y transmiten esa forma de pico con más frecuencia que los demás.

More HS-LS4 Biological Evolution lessons

Advantageous Traits SpreadHS-LS4-3AdaptationHS-LS4-4Environmental Change and SpeciesHS-LS4-5Simulating ConservationHS-LS4-6

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