ap bio chapter 19: Concept 19.1: The Darwinian revolution challenged traditional views of a young Earth inhabited by unchanging species

What was the traditional belief about Earth and species before Darwin?

Earth was young, and species were created as they are, without change.

How did Darwin’s ideas challenge traditional beliefs?

He proposed that species evolve over time, rather than being unchanging creations.

What historical influences shaped Darwin’s theory?

Other scientists’ work, including geology and paleontology, influenced his thinking.

What was Aristotle’s view on species?

Species were fixed, unchanging, and arranged on a scala naturae (scale of nature) by increasing complexity.

How did the Old Testament influence early views on species?

It taught that species were individually created by God and were perfect, meaning they could not change.

How did Carolus Linnaeus interpret organismal adaptations?

He believed adaptations were evidence that a Creator had designed each species for a purpose.

What is taxonomy?

The branch of biology that classifies and names organisms.

What was Linnaeus’s contribution to taxonomy?

He developed the binomial nomenclature system (e.g., Homo sapiens).

How are species names formatted in binomial nomenclature?

The genus is capitalized, the species is lowercase, and both are italicized or underlined.

What is evolution?

Evolution is change over time in species.

What role do fossils play in evolutionary theory?

Fossils provide evidence of organisms from the past, showing changes over time.

Where are fossils found?

In sedimentary rock, which is layered in strata (singular: stratum).

How do strata provide clues about fossil age?

Younger strata contain more recent fossils, while deeper strata contain older fossils.

Who was Georges Cuvier, and what did he propose?

A French scientist who developed paleontology and proposed catastrophism.

What is catastrophism?

The idea that boundaries between rock layers represent catastrophic events that wiped out species.

How did Cuvier explain the disappearance of fossils in certain strata?

He believed each new rock layer represented a mass extinction followed by the appearance of new species.

What did James Hutton propose about Earth’s surface?

It changes slowly over time due to continuous processes, not sudden catastrophes.

How did Charles Lyell expand on Hutton’s ideas?

He proposed that these slow, continuous changes have always occurred and will continue indefinitely.

How did Lyell’s work influence Darwin?

It reinforced the idea that gradual changes over long periods lead to evolution.

What was Lamarck’s theory of evolution?

Organisms evolve through the use and disuse of body parts and inheritance of acquired traits.

What did Lamarck propose about giraffes?

He believed giraffes originally had short necks, but their necks grew longer over generations because they stretched them to reach trees.

What was the idea of use and disuse?

Used body parts grow stronger and larger, while unused parts weaken and disappear.

Did Lamarck’s mechanisms have scientific support?

No, his ideas were later disproven as acquired traits are not inherited genetically.