AP Bio Chapter 22

Identify the three significant historical themes that set the stage for Darwinian evolutionary theory.
A. Classification of Species by Linnaeus
B. Uniformitarianism (the belief that processes occurring today also occurred in the past at the same rate)
C. Lamarck’s (incorrect) hypothesis on evolution

What were the two major points made in The Origin of Species?
A. Descent with modification explains unity and diversity of life
B. Natural selection brings about a match between organisms and their environment

What were the conventional paradigms in the 1800s when Darwin developed his theories?
It was believed that species did not evolve or change and were created exactly as they look today.

What was the contribution of Carolus Linnaeus to the evolutionary theories?
Linnaeus sorted organisms by characteristics, and each category probably represented a common ancestor between the organisms in the category.

How did the study of fossils help Darwin shape his theories?
Fossils show many different species with slightly different traits, showing that they evolved from one another.

How did geological gradualism and uniformitarianism influence Darwin?
Fossils and geological evidence did not support the theory of an earth that was only thousands of years old.

Identify the two principles of Lamarck’s theory of evolution.
A. Traits are passed down from parents to offspring (correct)
B. Acquired traits can be passed down through use and disuse (incorrect)

How did the observations during his voyage on the Beagle influence Darwin’s theories?
He observed that many similar organisms, like finches, had adaptations that made them better suited to their environment.

Why were the Galápagos Islands so important to Darwin’s observations?
They had many different species that had adapted from the mainland animals. Their speciation throughout the islands showed him how adaptation helped evolve animals.

What are the elements for the formation of new species?
There must be biological niches for the species to adapt and fill.

What is the driving force behind the evolution of the 14 species of finches on the Galapagos?
The food available differed on the islands, so they had to adapt to survive. They had to fill different ecological niches.

What was Wallace’s role in the Theory of Natural Selection?
He developed a theory similar to Darwin’s, encouraging Darwin to publish his works first.

Define Descent with modification.
Animals coming from a common ancestor develop traits that allow them to adapt to various environments. When an adaptation is favorable, the organism possessing it ends up leaving offspring with the same adaptation and natural selection works its way through until this trait has the advantage and is (most likely) the majority.

How does the “tree analogy” represent the evolutionary relationships of creatures?
Species “branch off” from existing common ancestors making a tree.

Summarize the observations recognized as the backbone of evolution by natural selection.
1. Members of a population often have varied traits
2. Traits are inherited from parents to offspring
3. All species are capable of producing more offspring than the environment can support
4. Due to lack of food and resources, many offspring do not survive

Summarize the inferences recognized as the backbone of evolution by natural selection.
1. Individuals whose traits give them a higher probability of surviving and reproducing in an environment tend to leave more offspring than others
2. The unequal ability of individuals to survive and reproduce will lead to an accumulation of favorable traits in the population over generations.

How did Darwin’s experience with artificial selection influence his theories of evolution?
Darwin had conversations with plant and animal breeders and noticed them purposefully breeding those with the desirable traits and wondered if this occurred in the natural world. From his observations on the Galápagos Islands, he did observe this and formulated his theory of evolution by natural selection.

How did Darwin’s experience with artificial selection influence his theories of evolution?
Darwin had conversations with plant and animal breeders and noticed them purposefully breeding those with the desirable traits and wondered if this occurred in the natural world. From his observations on the Galápagos Islands, he did observe this and formulated his theory of evolution by natural selection.

Indicate how paleontology is used as evidence of evolution by natural selection.
Paleontology– the fossil record shows a live record of what has existed on earth and about how long it existed. It can help show how an organism adapted to its environment

Indicate how biogeography is used as evidence of evolution by natural selection.
Biogeography– the branch of biology that deals with the geographical distribution of plants and animals.

Indicate how resistance to insecticides is used as evidence of evolution by natural selection.
Resistance to insecticides– this is an adaptation to survive. Insects with an already inborn resistance to the insecticide will not be affected as severely as insects without it. The can NOT look at other bugs dying and suddenly be immune, the gene for immunity has to already be present.

Indicate how drug resistance is used as evidence of evolution by natural selection.
Drug resistance– this is the exact same as the resistance to insecticides. The gene has to already be present. Those with immunity survive while the other die out and eventually all that remains is drug resistant organisms.

Indicate how homology is used as evidence of evolution by natural selection.
Homology– The study of similar structures in different species

Indicate how homologous structures are used as evidence of evolution by natural selection.
Homologous structures– these are structures that multiple organisms possess due to a common ancestor

Indicate how vestigial organs are used as evidence of evolution by natural selection.
Vestigial organs– these are body parts that remain despite not being beneficial to the organism. They simply never left and don’t harm the organism. (i.e. pelvic bone in whales or appendix/tailbone in humans)

Indicate how embryology is used as evidence of evolution by natural selection.
Embryology– The study of similarities in the embryos of different species

Indicate how biochemical similarity is used as evidence of evolution by natural selection.
Biochemical similarity– All organisms contain similar elements, like carbon and oxygen