AP Biology: Chapter 19 - Descent with Modification

What mechanism for evolutionary change did Charles Darwin propose in 'On the Origin of Species'?

Darwin proposed natural selection as the mechanism for evolutionary change.

How does Darwin define evolution?

Evolution is the change in allele frequencies in a population over generations.

What is adaptation according to evolutionary theory?

Adaptation refers to inherited characteristics that enhance an organism’s ability to survive and reproduce in a specific environment.

What are the key differences between Aristotle’s scala naturae and Carolus Linnaeus’ classification scheme?

Aristotle's scala naturae is a hierarchical structure ranking organisms from simplest to most complex with fixed species, while Linnaeus' system uses binomial nomenclature and groups organisms based on shared characteristics.

Who is associated with the theory of catastrophism and what does it propose?

Georges Cuvier associated with catastrophism, which suggests that Earth's history is shaped by sudden, short-lived, violent events.

What does James Hutton's theory of gradualism propose?

James Hutton proposed that geological changes occur slowly over long periods.

What is uniformitarianism and who proposed this theory?

Uniformitarianism, proposed by Charles Lyell, suggests that Earth's processes are uniform over time.

What mechanism for evolutionary change did Jean-Baptiste de Lamarck propose, and why was it rejected?

Lamarck proposed the inheritance of acquired characteristics. It was rejected because acquired traits do not alter DNA, and genetic changes occur through mutations and selection.

What observations did Darwin make on the HMS Beagle that supported his theory of evolution?

Darwin observed variations in species across different islands, leading him to conclude that species adapt to environments over time.

How did the principle of gradualism influence Darwin's ideas about evolution?

Darwin applied the idea of gradual changes over long periods from geology to biology, explaining the gradual evolution of species.

What does 'descent with modification' mean in Darwin's theory?

It means that all species share common ancestors and, over time, small heritable changes accumulate, leading to diversity.

What types of evidence convinced Darwin that species change over time?

Fossils, biogeographical distribution of species, homologous structures, and direct observations of adaptations.

How does Linnaeus’ classification scheme align with Darwin’s theory of evolution?

Linnaeus grouped organisms by shared traits, indicating that species that appear similar often share a common ancestor.

What three observations did Darwin make that led to the inference of natural selection?

1. Organisms produce more offspring than can survive. 2. There is heritable variation among individuals. 3. Those with advantageous traits survive and reproduce.

How did Thomas Malthus’ essay influence Darwin's thinking?

Malthus argued that populations grow faster than resources, leading Darwin to conclude that this competition allows only the fittest to survive.

What is the difference between artificial selection and natural selection?

Artificial selection is when humans breed organisms for desired traits, while natural selection is when nature selects traits that enhance survival and reproduction.

Why can't an individual organism evolve?

Evolution occurs at the population level as allele frequencies change; an individual’s genes remain the same.

What experiment supported Endler's hypothesis regarding guppy populations?

Endler moved guppies from high-predation to low-predation environments and found brighter-colored guppies survived better in low-predation areas.

How do homologous and vestigial structures support Darwin's theory of natural selection?

Homologous structures suggest common ancestry while vestigial structures are remnants of ancestral traits.

How does evidence from biogeography support the theory of evolution by natural selection?

Species in similar environments evolve differently based on geographic isolation.

What is the difference between colloquial and scientific uses of the term 'theory' in relation to Darwinism?

Colloquial theory is a guess, while a scientific theory is a well-supported explanation based on extensive evidence. Evolution is a scientific theory supported by various forms of evidence.