Q: Which equation would you use to calculate the percent sequence divergence for mtDNA between two populations?

$$D = \frac{\text{Number of differences}}{\text{Total number of base pairs}} \times 100$$

Question 1

According to Darwin's central thesis in 'On the Origin of Species,' which process is primarily responsible for the formation of new species in isolated populations?

Accepted Answer

Natural selection

Question 2

Which concept, popularized by Ernst Mayr, defines species as groups of actually or potentially interbreeding natural populations that are reproductively isolated from other such groups?

Accepted Answer

Biological Species Concept

Question 3

In the context of speciation, what is vicariance?

Accepted Answer

The physical division of a once-contiguous species range via the formation of a barrier to dispersal

Question 4

Which of the following is a premating barrier to reproduction?

Accepted Answer

Ecological isolation

Question 5

A population of Anthoxanthum odoratum diverged by evolving self-compatibility and reduced flowering time due to selection for tolerance of lead and zinc. This is an example of which mode of speciation?

Accepted Answer

Parapatric speciation

Question 6

Which equation best represents the exponential growth of a population, a concept central to Darwin's theory of the 'struggle for life'?

Accepted Answer

$$N(t) = N_0$ e$$^{rt}$$

Question 7

Which of the following statements about genetic bottlenecks is correct?

Accepted Answer

Genetic bottlenecks tend to result only in the loss of rare alleles unless the population is small for a relatively long period of time

Question 8

Which mode of speciation occurs when a barrier arises and populations evolve reproductive isolation in isolation?

Accepted Answer

Allopatric speciation

Question 9

In founder effect speciation, which process is most likely to drive diversification into a new ecological niche after the population grows?

Accepted Answer

Selection

Question 10

Which of the following best describes sympatric speciation?

Accepted Answer

Speciation occurs within a population without spatial segregation, often due to genetic change or ecological niche differentiation

Question 11

Which real-world example illustrates the process of vicariance leading to allopatric speciation?

Accepted Answer

The formation of the Isthmus of Panama separating marine species

Question 12

Which of the following is NOT a prediction of founder effect speciation?

Accepted Answer

Hybridization between the founding population and the ancestral population increases genetic diversity

Question 13

Which of the following is a key stage in the process of organismal diversification according to Dobzhansky?

Accepted Answer

Reproductive isolation

Question 14

Which equation would you use to calculate the percent sequence divergence for mtDNA between two populations?

Accepted Answer

$$D = \frac{	ext{Number of differences}}{	ext{Total number of base pairs}} 	imes 100$$

Question 15

Which scenario best exemplifies parapatric speciation?

Accepted Answer

Adjacent populations experience different selective pressures and gene flow is much weaker than divergent selection

Question 16

Which of the following is NOT a mode of speciation described in the modern synthesis?

Accepted Answer

Hybridogenic

Question 17

Which process is most likely to result in the loss of rare alleles in a population?

Accepted Answer

Genetic bottleneck

Question 18

Which of the following is a real-life example of sympatric speciation?

Accepted Answer

Rhagoletis pomonella flies diverging on apple and hawthorn trees

Question 19

Which step is NOT part of the three-step process of speciation?

Accepted Answer

Hybrid vigor increases

Question 20

Which of the following best describes the classic view of species held by Aristotle?

Accepted Answer

Species are fixed and unchanging, with eternal forms or essences

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