Evidence for Evolution

Question 1

define evolution

Answer 1

Change in the genetic composition of the population (allele frequencies) from one generation to the next

Question 2

define theory

Answer 2

• an overarching concept that explains a large number of facts and observations about the natural world
• can be used to make predictions about future observations
• has such weight and scope
• explains so many facts that it is unlikely to be refuted, although it may be refined as one tests the predictions it generates.

Question 3

what is the special creation theory

Answer 3

• the idea that species are immutable and do not change overtime
• they are independently created and never change

Question 4

what are the four components for the theory of biological evolution

Answer 4

1. microevolution
2. speciation
3. macroevolution
4. common ancestry

Question 5

4 components of biological evolution - microevolution

Answer 5

• change in allele frequencies and trait distributions that occur within populations and species
• on a small time scale

Question 6

4 components of biological evolution - speciation

Answer 6

• one species splits into two or more species
• use the biological species concept to define a species

Question 7

4 components of biological evolution: speciation - biological species concept

Answer 7

• species are populations, or groups of populations, within and among individuals which individuals actually or potentially interbreed and outside of which they do not interbreed
• can be a genetic or behavioral barrier

Question 8

4 components of biological evolution - macroevolution

Answer 8

evolution above the level of a species

Question 9

4 components of biological evolution - common ancestry

Answer 9

species are not independently derived, but instead has evolved from common ancestors and, thus, all species are related

Question 10

evidence of microevolution

Answer 10

• artificial selection
• natural populations - Broder’s paper
• lab experiments - fruit fly experiment (also evidence of speciation)

Question 11

evidence of microevolution: artificial selection - define the term

Answer 11

the selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits

Question 12

evidence of microevolution: artificial selection - what is the Garland et al. experiemnt

Answer 12

• they took mice that naturally ran on their wheels and bred them with other rats that ran on their wheel
• ones that were artificially selected, ran more frequently than those that did not

Question 13

evidence of microevolution: artificial selection - how is the Garland et al. experiment different from training mice to run via reward

Answer 13

• VIST (Variance, Inheritable, Selection, and Time): this would have no I or T
• training mice to run is not inheritable

Question 14

evidence of microevolution: natural populations - explain Broader’s paper

Answer 14

• there were 4 introduction sites where there were no predators
• let the fishes reproduce in the lab

Question 15

evidence of microevolution: Broader’s paper - what were the prediction and results

Answer 15

• predication: larger genitalia in low predation areas since female choice is the dominating selective factor
• results: introduced population evolved shorter genitalia (agrees with prediction)

Question 16

evidence of microevolution: Broader’s paper - why is it important to rear them in the lab rather than just measuring males collected from streams

Answer 16

remove confounding variables

Question 17

evidence of microevolution: lab experiments - explain the fruit fly experiment (also evidence of speciation)

Answer 17

• researchers took fruit flies and fed one group starch (they did not like) and the other was fed maltose (the did like)
• they simulated 40 generations of evolution by natural selection

Question 18

evidence of microevolution: fruit fly experiment - ‘40 generations of evolution by natural selection’ what does it mean

Answer 18

• some fruit flies died when put on starch but those that survived reproduced
• so the selective force = diet

Question 19

evidence of microevolution: fruit fly experiment - what did the experiment test for

Answer 19

reproductive isolation between the populations

Question 20

evidence of microevolution: fruit fly experiment - what were the predictions

Answer 20

• starch flies evolve to eat starch
• the flies will start to have some separation (not speciation since the time scale is too short)

Question 21

evidence of microevolution: fruit fly experiment - what was the results

Answer 21

• the data was consistent with the prediction
• researchers saw early stages of a reproductive isolation or mating barrier (early evidence of speciation)

Question 22

evidence of microevolution: fruit fly experiment - what was seen in the experimental group

Answer 22

• assortative mating
• groups mate with others that are similar to each other rather than different

Question 23

with all the evidence of microevolution, what is the evolutionary interpretation of microevolution

Answer 23

• species are not fixed (immutable)
• their characteristics change overtime

Question 24

evidence of speciation

Answer 24

• stickleback population
• law of speciation (also evidence of macroevolution)
• traditional forms (also evidence of macroevolution)

Question 25

evidence of speciation: stickleback population - what was the prediction

Answer 25

if speciation is a process, then we should be able to observe species with populations in various stages of speciation

Question 26

evidence of speciation: stickleback population - what are the steps of speciation

Answer 26

1. interbreeding population 2. distinguishable and hybridize (mate/breed) occasionally 3. distinguishable, hybridize rarely, hybrids have low fitness 4. distinguishable, hybridize rarely, hybrids are infertile, now completely different species

Question 27

evidence of speciation - what is the law of succession

Answer 27

- correspondence between fossil and living forms from the same local - also evidence of macroevolution

Question 28

evidence of macroevolution - transitional forms

Answer 28

- species showing a mix of features including traits typical of ancestral populations and novel traits seen later in descendants - also evidence of macroevolution and common ancestor

Question 29

evidence of macroevolution: transitional forms - examples

Answer 29

- birds and dinosaurs: *Archaeopteryx* is a transitional form that has a mix of traits from birds and reptiles - transition to land and back to water: the Blenny is a terrestrial fish where as a child it lives in the water but as an adult it lives on land and will jump out of water if knocked in

Question 30

with all the evidence of speciation, what is the evolutionary interpretation of speciation

Answer 30

1. species not only change overtime, but they also spawn new species 2. observation of stickleback populations at various stages of speciation process is consistent with the hypothesis that speciation is constantly taking place in nature

Question 31

what is the evidence for a common ancestor

Answer 31

- homology - genetic code - vestigial structure

Question 32

evidence for common ancestor - homology

Answer 32

- similarity between species that results from inheritance of traits from a common ancestor - can be structural or molecular

Question 33

evidence for common ancestor: homology - what is the evolutionary interpretation of homologous limb structure

Answer 33

All vertebrates descended from a common ancestor, from which they inherited the fundamental design of their limbs

Question 34

evidence for common ancestor: homology - define analogous structures

Answer 34

- similar structures because the animals evolved in a similar environment and traits have "converged" - happens through convergent evolution (same traits, different ancestor)

Question 35

evidence for common ancestor - genetic code

Answer 35

- an example of molecular homology - every organism has a universal molecular homology (genetic code) - DNA evolved once and every living thing has the same DNA

Question 36

evidence for common ancestor: genetic code - evolutionary interpretation of genetic code homology

Answer 36

all organisms inherited their genetic code from a common ancestor

Question 37

evidence for common ancestor - vestigial structure

Answer 37

a useless or rudimentary version of a body part that has an important function in other closely related species

Question 39

evidence for common ancestor - evolutionary interpretation of vestigial structures

Answer 39

Species with vestigial structures are descended, with modification, from ancestors in which the structure in question was fully formed and functional