AI generated deck from ch 18 notes

Question 1

Who famously stated that ‘nothing makes sense in biology except in the light of evolution’?

Answer 1

Theodosius Dobzhansky

Question 2

What is the theory of evolution considered in biology?

Answer 2

The unifying theory of biology

Question 3

Define adaptation.

Answer 3

Heritable trait or behavior in an organism that aids in its survival and reproduction in its present environment.

Question 4

What is the difference between convergent and divergent evolution?

Answer 4

Divergent evolution is when groups evolve in diverse directions from a common point, while convergent evolution is when groups independently evolve to similar forms.

Question 5

What are homologous structures?

Answer 5

Parallel structures in diverse organisms that have a common ancestor.

Question 6

What are vestigial structures?

Answer 6

Physical structures present in an organism that have no apparent function and appear to be from a functional structure in a distant ancestor.

Question 7

Name a key misconception about the theory of evolution.

Answer 7

Evolution is just a theory.

Question 8

Who reintroduced ideas about the evolution of animals in the 18th century?

Answer 8

Georges-Louis Leclerc Comte de Buffon

Question 9

What did Charles Lyell contribute to the understanding of Earth’s geology?

Answer 9

He popularized the notion of the greater age of Earth, allowing more time for gradual change in species.

Question 10

What mechanism for evolutionary change did Jean-Baptiste Lamarck propose?

Answer 10

Inheritance of acquired characteristics.

Question 11

What are the three principles of natural selection proposed by Darwin?

Answer 11

1. Most characteristics of organisms are inherited.
2. More offspring are produced than are able to survive.
3. Offspring vary among each other in regards to their characteristics.

Question 12

What is genetic variation?

Answer 12

Genetic differences among individuals in a population.

Question 13

What is the significance of fossils in the study of evolution?

Answer 13

Fossils show gradual evolutionary changes over time via carbon dating.

Question 14

Define biogeography.

Answer 14

The branch of biology that deals with the geographical distribution of plants and animals.

Question 15

What is molecular biology’s contribution to evidence of evolution?

Answer 15

DNA’s universality reflects evidence of a common ancestor for all of life.

Question 16

True or False: Individuals evolve.

Answer 16

False

Question 17

What does speciation refer to?

Answer 17

Formation of a new species.

Question 18

What is allopatric speciation?

Answer 18

Speciation that occurs via geographic separation.

Question 19

What is sympatric speciation?

Answer 19

Speciation that occurs in the same geographic space.

Question 20

What is adaptive radiation?

Answer 20

Speciation when one species radiates to form several other species.

Question 21

What are prezygotic barriers?

Answer 21

Reproductive isolation mechanisms that occur before zygote formation.

Question 22

Fill in the blank: The _______ is a situation that occurs when a species is reproductively independent from other species.

Answer 22

reproductive isolation

Question 23

What type of reproductive barrier occurs when fertilization takes place but hybrid individuals cannot survive?

Answer 23

Hybrid inviability

Question 24

What is hybrid sterility?

Answer 24

A postzygotic situation where hybrid birth occurs but the offspring are sterile.

Question 25

What is the gradual speciation model?

Answer 25

A model showing how species diverge gradually over time in small steps.

Question 26

What is punctuated equilibrium?

Answer 26

A model for rapid speciation that can occur when an event causes a small portion of a population to diverge quickly.

Question 27

What happens when hybrids are less fit than the parents?

Answer 27

Speciation reinforcement occurs, leading to continued divergence until they can no longer mate and produce viable offspring. ## Footnote This process emphasizes the importance of reproductive barriers in maintaining species integrity.

Question 28

What occurs if reproductive barriers weaken?

Answer 28

Fusion occurs and the two species become one. ## Footnote This indicates that the stability of species can be influenced by the fitness of hybrids.

Question 29

What is the outcome if hybrids are fit and reproductive?

Answer 29

Stability may occur and hybridization continues. ## Footnote This suggests that hybrids can play a significant role in the evolutionary process.

Question 30

Define the gradual speciation model.

Answer 30

A model that shows how species diverge gradually over time in small steps. ## Footnote This model contrasts with more abrupt speciation events.

Question 31

What is punctuated equilibrium?

Answer 31

A model for rapid speciation that can occur when an event causes a small portion of a population to be cut off from the rest of the population. ## Footnote This model highlights the impact of environmental changes on speciation rates.

Question 32

True or False: Hybrids typically tend to be more fit than their parent species.

Answer 32

False ## Footnote Generally, hybrids are considered less fit compared to their parent species.