AP Biology · Unit 7: Natural Selection
7.1 Introduction to Natural Selection
In short
You must understand natural selection as a major mechanism of evolution driven by competition for limited resources, leading to differential survival and reproduction. The concept of evolutionary fitness must be strictly defined in terms of reproductive success, rather than physical strength or survival alone.
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What else do you need to know about Introduction to Natural Selection?
You need to recognize that fluctuating biotic and abiotic environments affect the rate and direction of evolution, selecting for different genetic variations in each generation. It is crucial to distinguish that natural selection acts on individuals, but populations are the units that evolve. You must avoid Lamarckian reasoning and the use of buzzwords like 'fitness' without explaining the underlying concept of reproductive success.
Can you do these?
- I can state that natural selection is a major mechanism of evolution.
- I can explain that competition for limited resources results in differential survival, and individuals with favorable phenotypes are more likely to survive and reproduce.
- I can describe how evolutionary fitness is measured by reproductive success.
- I can explain how fluctuating biotic and abiotic environments affect the rate and direction of evolution by selecting different genetic variations.
How is Introduction to Natural Selection tested on the exam?
Questions may require you to describe characteristics of visual representations of biological concepts and processes (Skill 2.A). You are frequently penalized for using Lamarckian language (e.g., implying organisms intentionally adapt or acquire traits during their lifetime to survive). A common pitfall is using buzzwords like 'fitness' without explicitly connecting it to reproductive success and the passing of favorable phenotypes to offspring. Mark schemes expect precise language: you must clearly articulate that natural selection acts on individuals, but it is the population that evolves over time.
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Introduction to Natural Selection: common questions
What do you need to know about Introduction to Natural Selection for AP Biology?
You must understand natural selection as a major mechanism of evolution driven by competition for limited resources, leading to differential survival and reproduction. The concept of evolutionary fitness must be strictly defined in terms of reproductive success, rather than physical strength or survival alone.
How is Introduction to Natural Selection tested on the AP Biology exam?
Questions may require you to describe characteristics of visual representations of biological concepts and processes (Skill 2.A). You are frequently penalized for using Lamarckian language (e.g., implying organisms intentionally adapt or acquire traits during their lifetime to survive).
How do I know I have mastered Introduction to Natural Selection?
Check you can do each of these: state that natural selection is a major mechanism of evolution; explain that competition for limited resources results in differential survival, and individuals with favorable phenotypes are more likely to survive and reproduce; describe how evolutionary fitness is measured by reproductive success; explain how fluctuating biotic and abiotic environments affect the rate and direction of evolution by selecting different genetic variations.
Where does Introduction to Natural Selection fit in AP Biology?
Introduction to Natural Selection is topic 7.1 in Unit 7: Natural Selection of AP Biology.
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