A) Nature of Science
A1. Describe how: science is a process (how science builds knowledge), the
scientific method is flexible in nature, and how ‘choices’ are made among alternative
hypotheses in science.
• Iterative, tentative, dynamic
• Not linear approach, always ongoing and no set conclusion as new questions are raised
after old ones have been answered
• Scientific Argument= Scientific Idea + Expectations + Observations- may be in different
order and based on logical reasoning
• A scientific fact is a well-confirmed observation
a. Differentiate between alternative and null hypotheses.
• Research questions can be stated in terms of choices between two clear mutually
exclusive options. Null Hypothesis: the predicted difference between the experimental
and control groups does not occur. The only reason that the two groups are different is
• Alternative Hypothesis: predicted difference between experimental and control groups
based on the experimental variable
A2. Use the process of scientific inquiry to make effective decisions/arguments about
issues that have a biological component.
a. Evaluate alternative hypotheses to a scientific issue, justifying your choice, and
Identifying/formulate predictions based on each of the hypotheses.
b. Formulate a hypothesis based on a set of observations.
c. Design a study (observational or experimental), or evaluate an experimental design, to
test the hypothesis.
• Correlation is not causation!
• Not finding support for A does not support B
d. Explain why in scientific experimentation, controls are necessary, experimental
conditions must be kept as constant as possible, and repetition of tests is necessary.
• Controls must be held constant for the placebo effect
• Consilience- tested many times
A3. Compare and use the terms ‘hypothesis’ and ‘theory’ appropriately in their
• Hypothesis: testable idea, not used for proving, can be tested experimentally or
• explanation of broad phenomenon
• require you to make assumptions which can be independently tested for accuracy
• Theory: explanation: can be supported, rejected, or refuted, has been tested many
times and produced the same answer
• should have predictive power- fit additional observations not in theory- conceptual
• should be able to make inferences- logical conclusions based on observable facts A4. Distinguish and describe subject matter (and the criteria that make them so)
appropriate to scientific study.
• Subject matter should be from the natural world
A5. Describe and explain the limitations of science as a means to answer questions,
making reference to the scientific merits of Intelligent Design, Theistic Evolution, and
• Science can only investigate the laws of nature, science does not make moral
• Intelligent Design: God is supernatural, can’t be investigated, no predictions, cannot be
tested empirically, not falsifiable
• Theistic Evolution: can’t prove creator created Earth
• Evolution: can’t examine every single fossil, can’t observe the past
A6. Explain the concept of ‘irreducible complexity’ making reference to evidence
supporting/refuting its validity.
• Irreducible Complexity: an object cannot become simpler without being nonfunctional
• Single system composed of many interacting parts that contribute to basic function and
where the removal of one part causes the system to effectively cease functioning and
may even be detrimental
• Each of those parts in the system are indispensable
• Flagella has 40 different protein components- intelligent design say that the flagella is
useless without one of those components and it could not have emerged gradually
through natural selection
• 23 of these flagellum proteins found in other bacteria- showing variants, where only 2
are unique to flagella and the others closely resemble other proteins that carry out
functions in the cell- most of the components needed to make flagella might have
already been present in bacteria before the structure appeared
A7. Evaluate statements/claims critically, identifying them as pseudoscience,
anecdotal, or valid scientific claims.
A8. Analyze and draw conclusions from numerical and graphical data.
Pattern vs. mechanism component- TEbNS (pattern) characteristic of pop change over
time and related by common ancestor (mechanism) individual’s with certain heritable traits
produce more offspring
Prediction- well informed statement of what you expect to happen based on hypothesis
NOT a guess
Observational study vs. experimental study- experimental you control variables, give
treatments that cause changes and observe results
-In observational you use natural conditions where you look at relationships between natural
changes and do not assign treatments. Used when the treatment would be unethical eg.
Pregnant mother’s that drink and their effect on newborns-finding mothers that drink
compared to making mothers drink
• Observational studies do not have controls- we develop conceptual models- null model Pseudoscience- scientific sounding claim, not trustworthy and no methodical scientific
Ex: End of the world- 2012, psychotherapy, astrology, theistic evolution
Anecdotal- statistics of small numbers, include few observations where people conclude
link even though it is not rigorously studied
-Word of mouth recommendations, stories that contradict factual information, experiences of
a few people
Intelligent Design- diversity is too complex and therefore requires an intelligent designer
Theistic Evolution- harmonize evolutionary thought and God- god created earth but we
have evolved through natural selection
Theory of Evolution by Natural Selection- decent with modification, heritable traits
favored by environment result in reproductive success
Empirical- experimental and observable studies
Evidence- used to support/falsify hypothesis
Proof- NOT in science
Believe- NOT in science, scientists accept through multiple testing
Function- structures and behaviors of living things
Purpose- designed tools
B) History of Evolutionary Thought
B1. Relate Lamarck’s major contributions to evolutionary thought to Darwin’s
evolution by natural selection, explaining which of Lamarck’s hypotheses were
integral to Darwin’s idea, and which were not, providing reasons
• “inheritance of acquired characteristics”- organisms result from phenotypic changes in
response to the environment and these changes are passed on to offspring- hinting that
organisms change and become more complex because they have to but this is not true,
evolution does not have a goal
• Change through time- essential to Darwin and different from people’s ideas at that time
of life being unchanging
a) Explain why Lamarck’s hypotheses of use and disuse, and inheritance of acquired
characteristics leading to evolutionary change, are not supported.
• Evolution not based on how often a structure is used or not used but rather genetics.
And organisms behavior has no effect on its heritable characteristics
b) Identify statements/ideas as Lamarckian or Darwinian, justifying your choice.
• Lamarck: individuals change according to environments and pass changes on to
offspring. Evolution is progressive.
• Darwin: individuals don’t change, they produce more offspring and increase certain
allele frequencies according to selection posed by environment.
B2. Explain the influence of gradualism and uniformitarianism, and Malthus’s ideas of
population growth and food supply on Darwin’s ideas of natural selection and
• All these gave Darwin a geologic timeframe for Natural Selection
• Mathus: said that the population of offspring cannot be satisfied with the limited
resources available and therefore only some offspring survive. • Gradualism: Hutton- small changes in Earth result in big changes over time and
catastrophic events are not to blame for Earth today.
• Uniformitarianism: Lyell- processes that alter Earth are uniform through time. Also the
present is the key to the past and that geological processes that occurred in the past
occur at the same rate today.
B3. Summarize Darwin’s five observations and two inferences that encompass the
logic of his theory of evolution by natural selection and explain the link between the
• Most organisms produce more than one offspring
• Populations do not increase in size indefinitely
• Food and other resources are limited
• Individuals within a populations exhibit variability in many characteristics
• Many variations have genetic basis that is inherited by subsequent generations
• Individual’s in population will compete for resources
• Heritable traits that are advantageous will allow individuals to survive and reproduce
B4. Read a phylogenetic tree identifying common ancestors and speciation events;
explain what a
phylogenetic tree represents.
Node: descendant populations split and if two or more descendant groups emerge-
Tips (Terminal Nodes): represent those species living today or dead (extinct)
Linnean system of classification: kingdom, phylum, class, order, family, genus, and
Microevolution- changes in genetic characteristics of a population over time- genealogy-
Macroevolution- descent of different species from a common ancestor over many
generations- phylogeny- long term
Population- a group of interbreeding individuals in a specific geographical location
Typological thinking- species are unchanging and that variations among them are
Population thinking- variation among populations is key in nature of species
Scala Naturae/ladder of nature- species were organized based on complexity and
increased size, with humans on top
Fossil- any trace of an organism that lived in the past
Transitional fossil- is NOT direct ancestor- trait that is intermediate between old and new
species and shows change
Palaeontology- concerned with fossils
Habitat bias- dependent on areas where sediment is actively deposited, where there is little
O2 so that aerobic bacteria cannot decompose fossil, and high acidity so that bacteria
Taxonomic and tissue bias- hard parts more likely to leave fossil eg. Cartilage=weak
Temporal bias- recent fossils more common than old ones- some missing through plate
tectonics which eliminated certain layers of strata Abundance bias- number of species that exist
Vestigial trait- traits that have little to no function
Law of succession- fossils are similar to living species in that same geographic area
Tetrapod- four legged animal
Internal consistency- data from independent sources support predictions made by theory
Biogeography- study of geographic distribution of species
Dispersal- process of distributing things or people over a wide area
Homology (homologous)- shared between species that have a common ancestor, the
function of these traits doesn’t have to be in common with the ancestor
Convergent evolution- the independent evolution of similar features in species of different
Analogy- same function
Homoplasy- similarity of species of different ancestry- result of convergent evolution
Parsimony- particular trait that is unlikely to evolve independently from different linages
Developmental homology- human embryos have tails because common vertebrate
Genetic homology- occurs in DNA sequences -> seen through similarity in proteins
Structural homology- similarity in morphology
Phylogeny- hypothesizes a set of organisms’ evolutionary relationships to each other
Lineage- group arose from common ancestor
‘Struggle for existence’- results from the t