CurriculumGrade 12Science

Coevolution of Life and Earth

Aligned to HS-ESS2-7 — Next Generation Science Standards.

What this lesson teaches

Life and the planet have shaped each other throughout Earth's history. Living things changed the atmosphere, oceans, and rocks, and those changes in turn drove the evolution of new life, a two-way relationship called coevolution.

Worked example

Early cyanobacteria released oxygen through photosynthesis, and over hundreds of millions of years this oxygen built up in the atmosphere. That oxygen wiped out many organisms that could not tolerate it but made possible the complex, oxygen-breathing life that followed.

Practice questions

  1. Observe: Banded iron rock layers formed when oxygen first appeared in the oceans. What does that link between rock and early life suggest?
  2. Model: Draw a timeline showing how photosynthetic microbes changed Earth's atmosphere and how that atmosphere later shaped animal life.
  3. Explain: Construct an argument, using the rise of oxygen as evidence, that life and Earth's systems evolved together rather than separately.

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

Coevolución de la vida y la Tierra

La vida y el planeta se han moldeado mutuamente a lo largo de la historia de la Tierra. Los seres vivos cambiaron la atmósfera, los océanos y las rocas, y esos cambios a su vez impulsaron la evolución de nueva vida, una relación de doble sentido llamada coevolución.

Ejemplo: Las primeras cianobacterias liberaron oxígeno mediante la fotosíntesis, y a lo largo de cientos de millones de años ese oxígeno se acumuló en la atmósfera. Ese oxígeno eliminó a muchos organismos que no lo toleraban, pero hizo posible la vida compleja que respira oxígeno que vino después.

More Earth's Systems lessons

Building Landforms Over TimeHS-ESS2-1Feedbacks Between Earth SystemsHS-ESS2-2Convection in the MantleHS-ESS2-3Water Shapes Earth's SurfaceHS-ESS2-5The Carbon CycleHS-ESS2-6

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