theme 3

Question 1

simple definition of evolution

Answer 1

the notion that species change over time

Question 2

what was Aristotle’s idea about organisms?

Answer 2

Scala Naturae (Scale of Nature). classified each organism according to their complexity, which determines how close they are to perfection (god)

Question 3

what is the biblical account of creation?

Answer 3

organisms had been specially created by god, species could never change or become extinct, and new species could never arise

Question 4

what is natural theology?

Answer 4

detailed study of nature (considered god’s creation) in order to provide arguments for the existence of god

Question 5

what did Linnaeus do?

Answer 5

introduced the binomial species classification, which was based on grouping similar looking organisms into general categories.

Question 6

what did Linnaeus think was responsible for the similarity between certain species?

Answer 6

nothing. he just thought it was god’s design

Question 7

what did Georges Cuvier do?

Answer 7

found that many species had gone extinct, thought floods led to the number of species declining

Question 8

what did Charles Lyell do?

Answer 8

wrote “Principles of Geology” which said that landforms were not fixed, but changed slowly over time as a result of geological process. showed that Earth was much older than was assumed at the time

Question 9

how did Jean-Baptiste Lamarck contribute to Darwin’s idea of evolution?

Answer 9

he challenged the commonly held idea that organisms never change (proposed the idea of “transmutation”, what is now called evolution). the way he thought this happened was wrong but it inspired Darwin to think about inheritence

Question 10

how did Jean-Baptiste Lamarck think species changed?

Answer 10

organisms inherited acquired traits from their parents, and lose traits that are not used

Question 11

what is the perfecting principle?

Answer 11

the idea that organisms change (evolve into more complex ones) in order to ascend the Scale of Nature and become closer to perfection.

Question 12

who came up with the perfecting principle?

Answer 12

Lamarck

Question 13

what did Thomas Malthus do?

Answer 13

wrote “Principle of Populations” which said human population can increase faster than food supply, which leads to competition and survival of the fittest

Question 14

describe what a graph of quantity vs. time of population and food would look like according to Malthus’s idea

Answer 14

food increases linearly, and is at first greater than population.
population is exponential, and so crosses over and surpasses the quantity of food eventually

Question 15

what 3 major areas of study did Darwin get insights from?

Answer 15

1) geology and the fossil record
2) geographic distribution of species
3) comparative morphology of species

Question 16

what is biogeography?

Answer 16

the study of worldwide distribution of plants and animals

Question 17

what is a vestigial structure?

Answer 17

a useless structure in an organism that had a function in the organism’s ancestors

Question 18

what is homology?

Answer 18

the similarity present in a group of organisms because of shared ancestry

Question 19

what did Alfred Russel Wallace do?

Answer 19

he independently came to the same idea as Darwin about natural selection, but Darwin published his book first, which is why Wallace is not as well known, and Wallace had collected less evidence for it than Darwin.

Question 20

how does natural selection work?

Answer 20

inherited variation in traits is acted upon by natural selection caused by competition, which results in the more fit traits being passed down to offspring at a greater rate than the less fit. this causes the more fit (favourable) traits to be preserved and the less fit (unfavourable) to be destroyed)

Question 21

what is artificial selection?

Answer 21

selective breeding where only individuals with desired characteristics are bred together

Question 22

what is a population?

Answer 22

a group of individuals of a species that live together in a specific place

Question 23

what are Darwin’s 4 postulates?

Answer 23

1) individuals within a species vary
2) some variation is passed to offspring (heritable)
3) more offspring are produced than can survive and/or reproduce
4) survival and reproduction is not random, but is related to phenotypic variation

Question 24

the presence of what 3 things makes evolution inevitable?

Answer 24

1) variation in a trait
2) the variation is heritable
3) some variants reproduce more than other (have higher fitness)

Question 25

what is fitness?

Answer 25

reproductive success

Question 26

what are 3 aspects of fitness?

Answer 26

1) fitness is relative. the absolute number of offspring does not matter–what matters is how that number compares to that of others
2) a trait is only selected for if it increases fitness. if something like a longer lifespan does not result in more offspring being produced, then it will not be selected for
3) traits that increase fitness (are selected for) may change if something in the environment changes

Question 27

what does “genomes propose environments dispose” mean?

Answer 27

random mutations in the genome of an organism occur, “proposing” new things, and these things are disposed of by the environment through selection if they make the organism less able to compete in that environment

Question 28

what was the missing piece Darwin did not know allowed evolution to occur?

Answer 28

heritability works through DNA