Lesson 1 Flashcards
Aristolean view on evolution.
Individuals in a species are basically identical, the species itself is unchanging.
How does Buffon’s view changes within species differ from others?
Buffon believed that species changed through degradation; rather than adapting to their environment, species had degenerated since creation.
Explain Hutton’s (and then later, Lyell’s) view of uniformitarianism.
Changes in nature are gradual.
How would Cuvier explain the presence of transitional fossils?
Species are effectively recreated after catastrophes and fossils can be used to represent extinctions.
Explain Lamarckian evolution.
New species come from existing species through the inheritance of acquired traits.
State two ways in which Darwinian evolution differs from Aristolean.
1) Individuals within a population are different.
2) New species arise through natural selection.
Explain Darwinian evolution.
More individuals of a species are produced that can be supported by the available resources. Characteristics that allow for individuals to compete for successfully for these resources tend to increase in frequency as a result, populations of organisms change over time.
Developments in biology now suggest Lamarckian evolution may have some credence, why?
Although environmental factors that affect somatic cells do not affect the genetic code or the germ cells, epigenetic changes of how genes are expressed can be transmitted to offspring.
How are patterns of diversity on archipelagoes more consistent with a theory of evolution than with a theory of special creation?
Archipelago species strongly resemble species found on the nearest mainland.
When Darwin first proposed his theory of evolution, the mechanism for change was due to the blending of parental genes. Why would natural selection not work if this was the case?
Variation would not be maintained from generation to generation. It would be blended away, and favourable traits would be diluted out of the population.
Early estimates of the Earth’s age initially where inconsistent with natural selection being the mechanism behind evolution. How?
Estimates that underestimated the age of the Earth meant that descent with modification appeared to be too slow a process to explain observed biodiversity.
Scala naturae or the “ladder of nature” argues that ancestral species are inferior to derived species, and evolution is a form of progress toward perfection. How is this wrong?
Evolution isn’t oriented toward any goal except reproduction and survival. Organisms become more derived over time as their ancestors had specific traits were circumstantially suited for them to produce more offspring; allele frequency, therefore, changes circumstantially.
Linnaeus’s view on evolution.
Linnaeus saw each species as a separate act of creation, one by one.
