CurriculumGrade 9Science

Environmental Change and Species

Aligned to HS-LS4-5 — Next Generation Science Standards.

What this lesson teaches

When the environment changes, species with suited traits may thrive, others may decline, and isolated groups can diverge into new species. Species that cannot keep pace may go extinct.

Worked example

When a land bridge split one lizard population into two habitats, each group adapted separately over thousands of years until they could no longer interbreed, forming two new species.

Practice questions

  1. Describe how one environmental change affected a species' numbers.
  2. Show how a physical barrier could split one species into two over time.
  3. Evaluate evidence for whether a climate shift would more likely cause extinction or new species.

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

Cambio ambiental y especies

Cuando el ambiente cambia, las especies con rasgos adecuados pueden prosperar, otras pueden disminuir y los grupos aislados pueden divergir en nuevas especies. Las especies que no logran adaptarse a tiempo pueden extinguirse.

Ejemplo: Cuando un puente de tierra dividió una población de lagartijas en dos hábitats, cada grupo se adaptó por separado durante miles de años hasta que ya no pudieron cruzarse, formando dos nuevas especies.

More HS-LS4 Biological Evolution lessons

Four Factors of EvolutionHS-LS4-2Advantageous Traits SpreadHS-LS4-3AdaptationHS-LS4-4Simulating ConservationHS-LS4-6

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