Summarize the history of evolutionary thinking before Darwin, including the ‘argument from design’
The ‘argument from design’ (e.g., Paley’s watchmaker analogy) held that the complexity of life proved an intelligent creator.
How did changing views in geology and fossils set the stage for Darwin’s theory?
- James Hutton argued that the way rock strata were aligned, processes of erosion and sedimentation worked (and also fossil evidence),
indicated that the world must be inconceivably old - Lyell’s uniformitarianism
Outline Lamarck’s theory of evolution, including his mechanism
proposed that species become more complex over time. His mechanism was the inheritance of acquired characteristics, where traits an individual acquires during its lifetime (through use or disuse) are passed on to its offspring.
Describe key observations Darwin made on the Beagle voyage and how they influenced him.
Geology: Witnessed earthquakes uplifting land, saw marine fossils high in the Andes. Convinced him Lyell’s uniformitarianism was correct
Biogeography: Saw that Galápagos species (finches, tortoises) were unique to each island but resembled South American species
What were Darwin and Wallace’s two key insights and what evidence did they present?
Evolution (Descent with Modification): Species change over time and share common ancestors. Evidence: Homologous structures, fossil , biogeographic patterns.
Natural Selection
Natural selection
individuals with heritable traits better suited to their environment survive and reproduce more successfully, causing those traits to become more common in the population over time. Selective force
evolution
a change in allele frequency in a population across generation
observations in natural selection
- There is excess fertility such that more offspring are produced than the
environment can support. - Individuals vary
- Much of this variation is heritable
Artificial Selection
Humans are the selective force, breeding organisms for desired traits
What is experimental evolution and how does it provide evidence?
Manipulating conditions in replicate lab populations to observe and measure evolutionary change in real-time. It provides observable evidence that evolution by natural selection occurs
Counter these common misconception. explain each
Not Goal-Oriented
Not for Species’ Good:
how does Müllerian mimicry works?
Two or more distasteful or harmful species evolve to resemble each other. This shared “warning” appearance benefits all involved and predators quickly avoids all individuals displaying warning pattern
uniformitarianism
Geological features are shaped by slow, gradual processes over immense time.
what is “fitness”?
A measure of an individual’s capability to contribute its genes to the next generation, i.e., its reproductive success.
Why are creationism and intelligent design (ID) not considered scientific?
They are not testable or falsifiable. They rely on supernatural explanations that cannot be investigated with scientific methods (methodological materialism). They are faith-based beliefs that seek to confirm a pre-existing conclusion
what is structural homology? and does it support Darwin’s and Wallace’s thinking?
Structural homology describes the situation in which the underlying structure of a trait is similar across a set of species due to shared ancestry. This is more consistent with evolution because, when traits perform very different functions in present-day species, similarity of structure makes no sense from a design perspective, but it makes complete sense if it is due to common
ancestry.
biogeographic patterns observed by Darwin and Wallace and explain how these
contributed to their thinking on evolution
-species in a particular area tended to be similar to one another
-species in depauperate island chains are often quite similar to one another, despite exploiting very
different habitats/niches
-species on remote island chains are most similar to a nearby continental species
-species in similar habitats but in different areas are often not very similar to one another
