Every objective will NOT necessarily be covered during class time; you will be independently responsible for some of them.

  1. Explain Darwin’s key questions and observations from his voyage to the Galapagos
  2. Define biological evolution
  3. List the prerequisite conditions for evolution by natural selection to occur
  4. Distinguish between genotypic and phenotypic variation
  5. Explain how variations may be beneficial, detrimental, or neutral to their bearers; that their value depends upon the bearer’s environment at the time; and that their value can change as the environment changes
  6. List the sources of genetic/genotypic variation
  7. Explain why it is accurate to describe mutations as “rare, random, and regular”
  8. Explain the logic behind the statement: “phenotypic variations are not directed by the environment”
  9. Distinguish between interspecific competition and intraspecific competition, and identify which is the more significant driver of evolutionary change
  10. Analyze complex data sets to draw conclusions about evolutionary change and the conditions for it
  11. Identify conceptual and explanatory errors in poor explanations of evolutionary change, and write explanations of evolutionary change free of those errors
  12. Explain how natural selection leads to evolutionary change
  13. Define evolutionary or biological fitness
  14. Distinguish between evolutionary change due to natural selection and evolutionary change due to genetic drift
  15. Identify selective forces/selective pressures in examples of evolutionary change
  16. Explain how sexual selection differs from natural selection
  17. Analyze evolutionary trade-offs between sexual and natural selective forces
  18. Explain why selection does not produce organisms “perfectly” adapted to their environments
  19. Distinguish between three patterns of selection – stabilizing, disruptive, and directional
  20. Define and give an example of coevolution
  21. Define genetic drift, and explain why small populations are most susceptible to it
  22. Given examples of genetic drift, determine whether they are displaying a founder effect or a bottleneck effect
  23. Explain how genetic diversity affects a population’s ability to respond to changes in its environment and its risk for extinction, and identify which populations (more vs. less diverse) are at greater risk for disruption and extinction
  24. Calculate allele frequency within a gene pool
  25. Define Hardy-Weinberg Equilibrium
  26. List the conditions for a population to be in Hardy-Weinberg Equilibrium with respect to a particular gene, and explain why these conditions maintain equilibrium
  27. Calculate allele and genotype frequencies in populations at equilibrium using the Hardy-Weinberg principles/laws
  28. Apply the Hardy-Weinberg laws to evaluate whether or not a population is evolving
  29. Define and give an example of heterozygote advantage
  30. Define the biological species concept, and identify one of its limitations
  31. Explain what it means to say that “language is categories but life is a continuum” and how this relates to the concept of species
  32. Connect the concepts of “reproductive barriers” and “gene flow” to speciation
  33. Give examples of prezygotic and postzygotic barriers to reproduction, and be able to classify a barrier as being either prezygotic or postzygotic
  34. Classify examples of speciation as being allopatric or sympatric
  35. Recognize that speciation rates vary, and compare the gradualism and punctuated equilibrium models in describing patterns in speciation rates over time
  36. Explain how environmental stress can cause an increase in extinction, and how the availability of new habitats can cause an increase in speciation (particularly adaptive radiation)
  37. Explain polyploidy in plants as an example of highly rapid speciation
  38. Give examples of how evidence from a variety of fields can be used to uncover evolutionary history and mechanisms, including geology, geography, chemistry and physics, anatomy, embryology, and molecular biology
  39. Explain the broad relationship between similarity, relatedness, and recency of shared ancestry
  40. Use morphological evidence to draw conclusions about evolutionary history
  41. Contrast and define homologous vs. analogous structures
  42. Contrast divergent evolution with convergent/parallel evolution
  43. Define vestigial structures and use examples of vestigiality to draw conclusions about evolutionary history
  44. Use biochemical and genetic evidence, in particular DNA and protein sequences, to draw conclusions about evolutionary history
  45. Give examples of structural and molecular evidence for the common ancestry of all life, in particular the genetic code and metabolic pathways
  46. Explain what it means for a structure, feature, process, or pathway to be highly conserved
  47. Analyze protein and DNA sequences to determine relatedness and ancestry
  48. Select appropriate genes and proteins for study in answering different questions and including different groups of organisms
  49. Explain the concept of a “molecular clock”
  50. Analyze embryology to draw conclusions about evolutionary history
  51. Explain how artificial selection, antibiotic resistance, and industrial melanism illustrate modern and ongoing evolutionary change in response to human activity
  52. Given morphological, molecular, or fossil data, draw a parsimonious cladogram that represents traits derived from and/or lost due to evolution
  53. Analyze cladograms and phylogenetic trees to draw conclusions about relatedness and ancestry
  54. Classify clades as monophyletic, polyphyletic, or paraphyletic
  55. Explain how fossils demonstrate how life has changed over time, ideal vs. non-ideal conditions for fossil formation, and compare fossil dating methods*
  56. Describe key developments in the investigation into abiogenesis (the origin of life), including the Miller-Urey experiment and the RNA World hypothesis*
  57. Describe the major events in the history of the Earth and life upon it, as supported by geological, biological, and chemical evidence (lifelessness, followed by prokaryotic life, followed by eukaryotic life)*
  58. Describe the components of Earth’s atmosphere during the period in which life arose*

"*" = self-study

Enduring Understandings

Enduring Understandings are the College Board's AP Biology course concepts that you need to know for the AP exam. Below, you'll find those Enduring Understandings relevant to this unit. Numbering and lettering matches the document linked from the main page of this website.
Every Enduring Understanding will NOT necessarily be covered during class time; you will be independently responsible for some of them.

A. Change in the genetic makeup of a population over time is evolution.
1. Natural selection is a major mechanism of evolution.
  • a. According to Darwin’s theory of natural selection, competition for limited resources results in differential survival. Individuals with more favorable phenotypes are more likely to survive and produce more offspring, thus passing traits to subsequent generations.
  • b. Evolutionary fitness is measured by reproductive success.
  • c. Genetic variation and mutation play roles in natural selection. A diverse gene pool is important for the survival of a species in a changing environment.
  • d. Environments can be more or less stable or fluctuating, and this affects evolutionary rate and direction; different genetics variations can be selected in each generation.
  • e. An adaptation is a genetic variation that is favored by selection and is manifested as a trait that provides an advantage to an organism in a particular environment.
  • f. In addition to natural selection, chance and random events can influence the evolutionary process, especially for small populations.
  • g. Conditions for a population or an allele to be in Hardy-Weinberg equilibrium are (a) a large population size, (2) absence of migration, (3) no net mutations, (4) random mating, and (5) absence of selection. These conditions are seldom met.
  • h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
2. Natural selection acts on phenotypic variations in populations.
  • a. Environments change and act as selective mechanism on populations.
  • b. Phenotypic variations are not directed by the environment but occur through random changes in the DNA and through new gene combinations.
  • c. Some phenotypic variations significantly increase or decrease fitness of the organism and the population.
  • d. Humans impact variation in other species.
3. Evolutionary change is also driven by random processes.
  • a. Genetic drift is a nonselective process occurring in small populations.
  • b. Reduction of genetic variation within a given population can increase the differences between populations of the same species.
4. Biological evolution is supported by scientific evidence from many disciplines, including mathematics.
  • a. Scientific evidence of biological evolution uses information from geographical, geological, physical, chemical, and mathematical applications.
  • b. Molecular, morphological, and genetic information of existing and extinct organisms add to our understanding of evolution.
  • c. Fossils can be dated by a variety of methods that provide evidence for evolution. These include the age of the rocks where a fossil is found, the rate of decay of isotopes including carbon-14, the relationships within phylogenetic trees, and the mathematical calculations that take into account information from chemical properties and/or geographical data.
  • d. Morphological homologies represent features shared by common ancestry. Vestigial structures are remnants of functional structures, which can be compared to fossils and provide evidence for evolution.
  • e. Biochemical and genetic similarities, in particular DNA nucleotide and protein sequences, provide evidence for evolution and ancestry.
  • f. Mathematical models and simulations can be used to illustrate and support evolutionary concepts.

B. Organisms are linked by lines of descent from common ancestry.
1. Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
  • a. Structural and functional evidence supports the relatedness of all domains.
  • b. DNA and RNA are carriers of genetic information through transcription, translation and replication.
  • c. Major features of the genetic code are shared by all modern living systems.
  • d. Metabolic pathways are conserved across all currently recognized domains.
  • e. Structural evidence supports the relatedness of all eukaryotes.
2. Phylogenetic trees and cladograms are graphical representations (models) of evolutionary history that can be tested.
  • a. Phylogenetic trees and cladograms can represent traits that are either derived or lost due to evolution.
  • b. Phylogenetic trees and cladograms illustrate speciation that has occurred, in that relatedness of any two groups on the tree is shown by how recently two groups had a common ancestor.
  • c. Phylogenetic trees and cladograms can be constructed from morphological similarities of living or fossil species, and from DNA and protein sequence similarities, by employing computer programs that have sophisticated ways of measuring and representing relatedness among organisms.
  • d. Phylogenetic trees and cladograms are dynamic (i.e. phylogenetic trees and cladograms are constantly being revised), based on the biological data used, new mathematical and computational ideas, and current and emerging knowledge.

C. Life continues to evolve within a changing environment.
1. Speciation and extinction have occurred throughout the Earth’s history.
  • a. Speciation rates can vary, especially when adaptive radiation occurs when new habitats become available.
  • b. Species extinction rates are rapid at times of ecological stress.
2. Speciation may occur when two populations become reproductively isolated from each other.
  • a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre- and post-zygotic mechanisms can maintain reproductive isolation and prevent gene flow.
  • b. New species arise from reproductive isolation over time, which can involve scales of hundreds of thousands or even millions of years, or speciation can occur rapidly through mechanisms such as polyploidy in plants.
3. Populations of organisms continue to evolve.
  • a. Scientific evidence supports the idea that evolution has occurred in all species.
  • b. Scientific evidence supports the idea that evolution continues to occur.

D. The origin of living systems is explained by natural processes.
1. There are several hypotheses about the natural origin of life on Earth, each with supporting scientific evidence.
  • a. Scientific evidence supports the various models.
  • b. Primitive Earth provided inorganic precursors from which organic molecules could have been synthesized due to the presence of available free energy and the absence of a significant quantity of oxygen.
  • c. In turn, these molecules served as monomers or building blocks for the formation of more complex molecules, including amino acids and nucleotides.
  • d. The joining of these monomers produced polymers with the ability to replicate, store and transfer information.
  • e. These complex reaction sets could have occurred in solution (organic soup model) or as reactions on solid reactive surfaces.
  • f. The RNA World Hypothesis proposes that RNA could have been the earliest genetic material.
2. Scientific evidence from many different disciplines supports models of the origin of life.
  • a. Geological evidence provides support for models of the origin of life on Earth.
  • b. The Earth formed approximately 4.6 billion years ago (bya), and the environment was too hostile for life until 3.9 bya, while the earliest fossil evidence for life dates to 3.5 bya. Taken together, this evidence provides a plausible range of dates when the origin of life could have occurred.
  • c. Chemical experiments have shown that it is possible to form complex organic molecules from inorganic molecules in the absence of life.
  • d. Molecular and genetic evidence from extant and extinct organisms indicates that all organisms on Earth share a common ancestral origin of life.
  • e. Scientific evidence includes molecular building blocks that are common to all life forms.
  • f. Scientific evidence includes a common genetic code.

E. Many biological processes involved in growth, reproduction and dynamic homeostasis include temporal regulation and coordination.
3. Timing and coordination of behavior are regulated by various mechanisms and are important in natural selection.
  • d. Responses to information and communication of information are vital to natural selection.
  • g. Behaviors in animals are triggered by environmental cues and are vital to reproduction, natural selection and survival.
  • h. Cooperative behavior within or between populations contributes to the survival of the populations.

C. The processing of genetic information is imperfect and is a source of genetic variation.
1. Changes in genotype can result in changes in phenotype.
  • a. Alterations in a DNA sequence can lead to changes in the type or amount of the protein produced and the consequent phenotype.
  • b. DNA mutations can be positive, negative or neutral based on the effect or the lack of effect they have on the resulting nucleic acid or protein and the phenotypes that are conferred by the protein.
  • d. Whether or not a mutation is detrimental, beneficial or neutral depends on the environmental context. Mutations are the primary source of genetic variation.
  • g. Changes in genotype may affect phenotypes that are subject to natural selection. Genetic changes that enhance survival and reproduction can be selected by environmental conditions.
  • h. Selection results in evolutionary change.
2. Biological systems have multiple processes that increase genetic variation.
  • a. The imperfect nature of DNA replication and repair increases variation.
  • c. Sexual reproduction in eukaryotes involving gamete formation, including crossing-over during meiosis and the random assortment of chromosomes during meiosis, and fertilization serve to increase variation. Reproduction processes that increase genetic variation are evolutionarily conserved and are shared by various organisms.

E. Transmission of information results in changes within and between biological systems.
1. Individuals can act on information and can communicate it to others.
  • e. Responses to information and communication of information are vital to natural selection and evolution.
  • f. Natural selection favors innate and learned behaviors that increase survival and reproductive fitness.
  • g. Cooperative behavior tends to increase the fitness of the individual and the survival of the population.

A. Interactions within biological systems lead to complex properties.
6. Interactions among living systems and with their environment result in the movement of matter and energy.
  • k. Many adaptations of organisms are related to obtaining and using energy and matter in a particular environment.

C. Naturally occurring diversity among and between components within biological systems affects interactions with the environment.
3. The level of variation in a population affects population dynamics.
  • a. Population ability to respond to changes in the environment is affected by genetic diversity. Species and populations with little genetic diversity are at risk for extinction.
  • b. Genetic diversity allows individuals in a population to respond differently to the same changes in environmental conditions.
  • c. Allelic variation within a population can be modeled by the Hardy-Weinberg equation(s).

Textbook Reference

This is the part of your textbook that covers the material for this unit.
Ch 19-23 and Ch 24 concept 24.1.

Relevant Files

Here, you'll find files for this course. Copies of lecture notes will go here, as will others.
Lecture Notes part 1:
part 2:

List of basic Excel skills needed for the Hardy-Weinberg Lab -

Complete the exercises in the following workbooks for tutorials on some of the most important and difficult of the Excel skills:

What Does T. rex Taste Like? - Student Folders 2, 3, and 4 provide a simple walkthrough and some practice with interpreting phylogenetic trees.


These connect to materials on other teachers' websites that you may find helpful. Generally speaking, I put links to helpful review materials - like video lectures summarizing the material - towards the top, and links to interesting extensions towards the bottom.
All About Fancy Males - Cornell Ornithology Lab introduction to sexual selection
A Brief History of Life (NOVA)
Origins (NOVA)
A cool 15 minute movie about human origins and evolution
Using the Origin of Life to Engineer Molecules
TalkOrigins FAQs about Evolution
Understanding Evolution
29 Evidences for Macroevolution
Observed Instances of Speciation 1 and 2
Evolution in the News
Human Family Tree: The Genographic Project
Human Evolution
Becoming Human documentary
Interactive Evolution
Recent study of sequential speciation in parasitic flies & wasps
Darwin's Collected Works
Paleontology Exhibits
The Tree of Life
Evolution of the Cell
The Lenski Experiment
Taxonomy of North America
Record Of Time: Intro to Fossil Dating
Major evolution research findings in 2009, 2010, 2011, and earlier
More Evolution Articles
Evolution of the Eye
About Darwin & History of Evolutionary Thought
History of Evolutionary Thought
Understanding Homology vs Analogy
Scitable from Nature: Essentials of Genetic Unit 5 Essentials of Genetics Population Level & Genetic Variation and Evolution
Rock Pocket Mouse Evolution Video -Great example of evolution in action!
HHMI's BioInteractive Short Films on "The Making of the Fittest" - additional short videos showing evolution and natural selection in action.
EVO-DEVO Rap from Stanford (from Autumn)
Timeline of Life on Earth
Ediacaran Fauna Fossils Podcast
Marine Iguana Podcast
Island Fox Podcast
Camel Adaptation Song
UC Berkeley Museum of Paleontology The History of Evolutionary Thought
Toxoplasma needs Cats and Rats to Reproduce
Nova: Dover Trial : Defining Science; Darwin's Predications; Fossil Evidence
Evolution YouTube (Stanford)
Evolution of Skin Color (TED talk)
Ken Miller on chromosomes on chimp and human
Chromosome breakpoint areas lead to speciation