Chapter 3: Evolutionary thought and theory

Question 1

3 Principles of science

Answer 1

1. there is a real and knowable universe
2. the universe operates according to understandable laws
3. these laws are unchanging

Question 2

4 Methods of science

Answer 2

1. Create one or more testable hypotheses to explain observations or answer questions
2. Test the hypothesis (or hypotheses)
3. Accept, modify or reject the hypothesis
4. Continually reevaluate the hypothesis as new data becomes available and new hypotheses are created

Question 3

Hypothesis

Answer 3

must be testable, there must be some way to collect & analyze data to support or reject it

Question 4

Theory

Answer 4

usually made up of multiple hypotheses and data that support the claim

Question 5

6 Key concepts in evolutionary theory

Answer 5

Mutation, natural selection, sexual selection, gene flow, genetic drift, adaptive radiation

Question 6

Mutation

Answer 6

1. Errors in the replication of DNA, the ultimate source of variation within populations
2. Can occur simply as copying errors or from exposure to radiation, chemicals and viruses
3. The reason why bipedalism and larger brains emerged in humans

Question 7

Sexual selection

Answer 7

Personal mate selection (choosing a mate based on physical features or cultural factors)

Question 8

Gene flow

Answer 8

When genes move between populations that are members of the same species but who do not normally mate together

Question 9

Genetic Drift

Answer 9

A random factor in evolution,
When changes in allele frequency occur by chance (ex- when a small group leaves its parent population and begins a new population elsewhere)

Question 10

Adaptive radiation

Answer 10

Occurs when a species rapidly adapts to an ecological niche, often expanding its population quickly and diversifying into multiple species

Question 11

What 2 models pertain to the speed at which evolution occurs

Answer 11

Gradualism & Punctuated equilibrium

Question 12

Gradualism

Answer 12

suggests a slow steady change with a new species eventually emerging

Question 13

Punctuated Equilibrium

Answer 13

suggests a slow steady change occasionally interrupted by short periods of significant change
explains the lack of transitional forms in the fossil record

Question 14

Species

Answer 14

a population of individuals that can mate and produce fertile offspring in the wild

Question 15

Speciation

Answer 15

the process by which new species emerge, can happen in numerous ways such as geographic isolation or a single population of species that evolves into another species

Question 16

Genetics

Answer 16

the study of individual genes and their role in inheritance

Question 17

Genome

Answer 17

the entire genetic makeup of an individual or species

Question 18

Genomics

Answer 18

the study of genomes

Question 19

Epigenetics

Answer 19

refers to the study of how factors other than DNA or genes may influence the occurrence of specific traits, can change a phenotype without a corresponding change in the genotype

Question 20

Mosaic evolution

Answer 20

a phenotypic pattern that shows how different traits of an organism, respond to different selection pressures may evolve at different rates

Question 21

Homo naledi

Answer 21

recent discovery of homo that showed possible evidence for burial practices

Question 22

Australopithecines

Answer 22

possibly emerged from Ardipithecus
adapted to bushlands, open savannah, and aquatic fringes

Question 23

entomophagy

Answer 23

eating insects

Question 24

Linnaeus

Answer 24

devised the naming system we still use for living organisms which was called Linnaean taxonomy

Question 25

Lamarck

Answer 25

proposed that organisms responded to their environments by changing and those changes would be passed on to subsequent generations (transformism)

Question 26

Cuvier

Answer 26

by studying the fossil record he came to believe that some species had been abruptly wiped out and replaced by a new species (catastrophism)

Question 27

Lyell

Answer 27

believed that the world was a product of gradual changes throughout time, these changes ongoing and that we can see them in geology (uniformitarianism) "the present is the key to the past"

Question 28

Great chain of being

Answer 28

hierarchical structure of life thought by medieval Christianity to have been decreed by God

Question 29

Charles Darwin

Answer 29

2 key elements: common origin and natural selection

Question 30

Common origin

Answer 30

studied by looking at phenotypes and later on genotypes as well and comparing the traits by relatedness

Question 31

Natural selection

Answer 31

there are differences between individuals that make them more or less likely to survive

Question 32

Darwins theory of evolution (Variational evolution) (4)

Answer 32

1. there is variation in a population 2. only part of a population reproduces 3. traits are heritable 4. advantageous traits eventually become more frequent in a population

Question 33

Gregor Mendels discoveries (4)

Answer 33

1. traits are determined by specific units or factors (genes) in individuals which are passed onto offspring 2. An individual inherits one unit from each parent (alleles) 3. Even though an individual has a specific trait, it may not be observable but can still be passed on 4. He is responsible for figuring out dominant & recessive alleles, and the differences between genotype & phenotype

Question 34

Microevolution

Answer 34

small evolutionary changes that occur within a single species over relatively few generations, involves ecological time, leads to alterations in the gene pool, ex- new strains of viruses

Question 35

Macroevolution

Answer 35

changes that lead to new species and their diversification across space and over millions of years, measured in geological time, leads to speciation, ex- development of bonobos and chimps from a common ancestor