Adaptations of Organisms (College Board AP® Environmental Science): Revision Note

Environmental adaptations of organisms

• Organisms adapt to their environment in three main ways:

  • Behaviorally

  • Physiologically

  • Structurally

1. Behavioral adaptations:

• Actions taken by organisms to survive in their environment

  • Example: Birds migrating to warmer regions during winter to avoid harsh climates

2. Physiological adaptations:

• Internal body processes that help organisms survive

  • Example: Desert animals like camels conserving water by producing concentrated urine

3. Structural adaptations:

• Physical features that improve survival and reproduction

  • Example: Arctic foxes having thick fur to insulate against the cold

Short-term and long-term adaptations

• Organisms adapt to their environment over time, both in short- and long-term scales

• Short-term adaptations (also known as acclimation):

  • Temporary, reversible physiological changes in response to immediate environmental conditions

  • These are not true adaptations in the evolutionary sense — they are not inherited, do not involve changes to DNA, and play no role in evolutionary processes

  • Example: A human's body acclimating to high altitudes by increasing red blood cell production

• Long-term adaptations:

  • Permanent changes that develop over many generations due to natural selection

  • These involve DNA changes at the genetic level and play a central role in evolutionary processes

  • Example: Giraffes evolving long necks to access food in tall trees

Responses of organisms to environmental changes

• Environmental changes, whether sudden or gradual, can threaten a species' survival

  • Sudden changes:

    • May require immediate responses, such as altering certain behaviors or moving to a new habitat

  • Gradual changes:

    • Species may adapt over multiple generations, but individuals often face challenges in survival and reproduction

• When environmental changes exceed a species' ability to adapt or speed of adaptation, the species may:

  • Alter behavior:

    • Example: Coyotes changing their activity patterns to become more nocturnal, helping them avoid human interaction and exploit food resources in urban areas during quieter nighttime hours

  • Migrate:

    • Example: Monarch butterflies shifting migration patterns due to climate-induced habitat changes

  • Perish:

    • Example: Extinction of species like the the golden toad (Incilius periglenes), which disappeared due to a combination of habitat loss and climate change that altered its breeding environment in the Monteverde Cloud Forest of Costa Rica