AP Biology · Unit 7
Natural Selection
In short
Unit 7: Natural Selection in AP Biology covers 12 topics: Introduction to Natural Selection, Natural Selection, Artificial Selection, Population Genetics and 8 more. Open each one for what you need to know, a self-check list and how it is tested on the exam.
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What is in Unit 7: Natural Selection?
Unit 7: Natural Selection
7.1 Introduction to Natural Selection
- 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.
7.2 Natural Selection
7.3 Artificial Selection
- I can describe data from a table or graph, including identifying specific data points, trends, patterns, and relationships between variables.
7.4 Population Genetics
- I can describe how mutation, genetic drift (including bottleneck and founder effects), and migration drive evolution through random occurrences.
- I can explain how mutations, genetic drift, and gene flow lead to changes in allele frequencies and affect population divergence.
7.5 Hardy–Weinberg Equilibrium
- I can list the five conditions required for a population to be in Hardy-Weinberg equilibrium and explain how it serves as a null hypothesis.
- I can calculate allele and genotype frequencies in a nonevolving population using the Hardy-Weinberg equations.
7.6 Evidence of Evolution
- I can describe the geographical, geological, physical, biochemical, and mathematical data that provide evidence for evolution.
- I can explain how fossils are dated and how morphological homologies, including vestigial structures, provide evidence of common ancestry.
7.7 Common Ancestry
- I can identify membrane-bound organelles, linear chromosomes, and genes that contain introns as evidence for the common ancestry of all eukaryotes.
7.8 Continuing Evolution
- I can provide examples of ongoing evolution, such as genomic changes, continuous fossil record changes, resistance to drugs or chemicals, and emergent diseases.
7.9 Phylogeny
- I can explain how traits gained or lost during evolution, including shared derived characters and molecular data, are used to construct phylogenetic trees and cladograms, and identify the out-group.
- I can use phylogenetic trees and cladograms to illustrate speciation and identify the most recent common ancestor at the nodes.
- I can construct phylogenetic trees and cladograms from morphological similarities and from DNA and protein sequence similarities.
7.10 Speciation
- I can explain that speciation occurs when two populations become reproductively isolated from each other.
- I can define a species using the biological species concept as a group capable of interbreeding and exchanging genetic information to produce viable, fertile offspring.
- I can distinguish between punctuated equilibrium and gradualism as different rates of evolution.
- I can describe how divergent evolution and adaptive radiation lead to rapid speciation when new habitats become available.
- I can explain how convergent evolution results in similar phenotypic adaptations in different populations due to similar selective pressures.
- I can differentiate between sympatric speciation (geographic overlap) and allopatric speciation (geographic isolation).
- I can describe how various pre-zygotic and post-zygotic mechanisms maintain reproductive isolation and prevent gene flow.
7.11 Variations in Populations
- I can describe how the level of variation in a population affects its ability to respond to environmental changes, and why populations with little diversity are at risk of extinction.
- I can explain why genetically diverse populations are more resilient to environmental perturbations.
- I can explain how an allele that is adaptive in one environment may be deleterious in another due to different selective pressures.
7.12 Origins of Life on Earth
- I can explain the geological timeline of early Earth and how it provides a plausible range of dates for the origin of life.
- I can describe the RNA world hypothesis and list its three key assumptions regarding early genetic material.
Natural Selection: common questions
What is in Unit 7: Natural Selection?
It covers 12 topics: 7.1 Introduction to Natural Selection; 7.2 Natural Selection; 7.3 Artificial Selection; 7.4 Population Genetics; 7.5 Hardy–Weinberg Equilibrium; 7.6 Evidence of Evolution; 7.7 Common Ancestry; 7.8 Continuing Evolution; 7.9 Phylogeny; 7.10 Speciation; 7.11 Variations in Populations; 7.12 Origins of Life on Earth.
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