Evolution Part 1

1. Who is the naturalist credited for the evolution theory?

Charles Darwin

2. What is the definition for evolution?

• Species change over time

3. What are the two animals that Darwin studied on the Galapagos

Islands and what characteristics did he study?

• Tortoises-different shell shapes to reach food

• -Finches-distinct beak shapes for different food

4. What is the idea that each living species has descended from older

species called?

• Descent with modification

5. Darwin's theory of evolution was based on _____ ______which

states that useful variations for their environment survive & reproduce successfully resulting in evolution

of a species. • Natural Selection

6 Phenotypes, physical traits, that are favorable and passed onto

offspring is associated with what memorable phrase?

• Survival of the Fittest!

7. How can lethal alleles be passed on through generations?

• It can be hidden by the dominant alleles/traits in carriers

8. What does natural selection act upon?

• The phenotype

9. What determines which variation is considered useful and passed

on? • The environment/nature

10. What are characteristics called that make individuals different

within the same species?• Variations

11. Does larger or smaller variations in a species increase the

chance of a species survival? Why?

• Increase

• They will be able to survive a larger variety of environmental situations

12. Are mutations good, bad, and/or neither?

• All of the above

13. What is a variation called that helps an organism survive in its

environment? • Adaptations

14. How are adaptations chosen and who/what chooses them?

• The adaptations that help the organism survive in the environment

15. What can happen to a species without the right adaptations?

• It can become extinct or endangered

16. What is it called when an organism blends into the

surrounding? Give an example.

• Camouflage- chameleon/walking stick/leaf frog

17. What is it called a species resembles a harmful species in

physical appearance or behavior? Give an example.

• Mimicry-hornet and bee

18. What are the four main causes of evolution?

• -Natural Selection

• -Migration

• -Genetic Drift

• -Mutation

19. What is the most common cause of offspring variation from sexual reproduction and gamete

formation?

• Gene shuffling

20. What is a random change in DNA that can cause evolution? List the 2 main types and define them.

• Mutation

• -Frameshift/Point Mutations

21.What is migration also known as?

• Gene flow

22.Genetic drift is a _____change in allele frequency

• random

23.Genetic drift affects ___ and ______ type of populations most.

• Small

• isolated

24.What is a change in allele frequency due to the migration of

small subgroups starting new populations?

• Founder effect

25.Does the founder effect cause identical populations to the ones

they migrated from? • No-it depends on the founding alleles

26.Nonrandom mating means that mates are chosen by how __ they

are, which leads to a ______ • Fit

• Better

27.What cause acts on the phenotype?

• Natural Selection

28.What is it called when there is no change in a population over

many generations? Does it occur often?

• Genetic equilibrium-it is very rare

29.What is the principle that allele frequency will remain the same

unless 1 or more factors change.

• Hardy-Weinberg

30.To achieve genetic equilibrium:

• No-mutations occur

• No-gene flow/migration in or out

• No-natural selection

• Yes-individuals mate randomly

• Yes-large gene pool

31.What is all of the alleles in a population called?

• Gene pool

32What does stabilizing selection favor? Draw a diagram.

• Favors the average individuals

33.What does stabilizing selection reduce?

• Reduces variations

34.What does directional selection favor? Draw a diagram.

• One extreme

35.Directional selection can lead to what?

• Rapid evolution of a new species

36.What does disruptive selection favor? Draw a diagram.

• BOTH extremes of the species

37.Disruptive selection can lead to what

• 2 new species?

38.What are the 5 main types of proof used for evolution?

• -Fossil Records (accumulation of fossil information)

• -Homologous structures

• -Vestigial structures

• -Embryonic structures

• -DNA similarities

39.What shows the accumulation of information that shows the pattern

of change amongst past living things?

• Fossil record

40.What are remains of earlier life called?

• Fossils

41.What type of rock are most fossils in?

• Sedimentary

42.What are the 5 main types of fossils?

• -Casts

• -Molds

• -Amber

• -Imprints

• -Petrified

43.What are the 3 main things that fossil records can prove? Briefly

describe each

• Biological diversity-kinds of organisms

• -Episodic speciation-when a new species appears

• -Mass extinction-when there is a sudden disappearance of an organism

44.What are the 2 main types of fossil dating? Briefly describe

each.• -Radioactive dating-measuring the

amount of radioactive element (Carbon 14 usually) left in the fossil

• -Relative Dating-Comparing fossils against other fossils from the same layer of Earth

45.How do you figure the half life?

• By measuring time it takes for ½ the radioactive element to decay

46What type of evidence shows similar patterns of an organisms' parts (though may have different functions) indicating

that they have recent common ancestors. Give an example

• Homologous structures-ex. Bird’s wing to human arm to penguin forelimb, to alligator arm to whale fin

47.What type of evidence is that an organism has a part that has no

current function, but was functional to their ancestors? Give an

example. • Vestigial structures-appendix, pelvic

bones in whales, wings for ostriches

48.What type of evidence shows similarities of the earliest stages of

life? Give an example.

• Embryology-mammals, birds, and reptiles all have tails and gill slits as embryos

49.What type of evidence shows a close relationship in the cells

codes? Give an example.

• DNA-chimpanzees are 98% chromosomally similar to humans

50.What type of evolution starts as 2 unrelated species that become

similar usually because of environment? Give an example

• Convergent evolution-sharks(fish), penguins(birds), & dolphins(mammals) are similar because they all adapt to the same habitat

51.What type of evolution starts as 2 species that evolve in response to each other? Give an example.

• Coevolution- poisonous plants and insects that become poison resistant

52.What type of evolution starts with 1 species that becomes different and creates 2 species, usually due to

differing habitats? Give an example • Divergent

Evolution- penguins, ostriches, and hummingbird all adapted & became different species

53.What type of evolution starts with 1 species and evolve into

many species? Give an example

• Adaptive radiation (Descent with Modification)-Finches evolved into many different species