Chapter 1. Chapter 15: Nonadaptive Evolution and Speciation

1.1 Introduction

Interactive Study Guide
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Welcome to the Interactive Study Guide for Chapter 15: Nonadaptive Evolution and Speciation! This Study Guide will help you master your understanding of the chapter's Driving Questions, using interactive Infographics and activities, as well as targeted assessment questions. Click "Next" to get started, or select a Driving Question from the drop-down menu to the right.

Urban Evolution:

How cities are altering the fate of species

DRIVING QUESTIONS

  • What is a gene pool (and can you swim in it)?
  • How do different evolutionary mechanisms influence the composition of a gene pool?
  • How does the gene pool of an evolving population compare to the gene pool of a nonevolving population?
  • How do new species arise and how can we recognize them?

1.2 Driving Question 1

Driving Question 1

What is a gene pool (and can you swim in it)?

Why should you care?

You may think of evolution as something that occurred a long time ago, before the existence of humans. The fact is, however, that evolution is continually occurring all around us, to us, and we, as humans, are now playing a role in the evolution of organisms as well. For example, 300 years ago, the island of Manhattan was a thick forest with a minimal human population. Compare that to the present day Manhattan of skyscrapers, subways, millions of people and segregated, sporadic spaces of green and you might begin to understand how we have affected not only the habitats of several populations of organisms, but also the frequency of alleles making up their gene pools. The white-footed mouse population in Manhattan is a good example of a population evolving in a relatively short period of time in response to the alteration of their environment by us, humans.

What should you know?

To fully answer this Driving Question, you should be able to:

  1. Define “gene pool”.
  2. Relate evolution to gene pools and allele frequencies.

Infographic Focus

The infographics most pertinent to the Driving Question are 15.1 and 15.2.

Question Test Your Vocabulary

Choose the correct term for each of the following definitions:

Term Definition
PGDg4iA0+G/F8/GtJeJX10Fv4hu+cbLOkdiTX6yq/GE= The total collection of alleles in a population.
XnzkS+wvJtOdhRKOIUVHGq1ZRmbj9020eg1DtEMzN20= The relative proportion of an allele in a population.
Table
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Define “gene pool”.

Question 1.1

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A gene pool is the collection of alleles in a particular population.

Question 1.2

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Yes, different populations of the same organism can have different gene pools. Different populations of the same organism can be under different selection pressures depending on a variety of conditions. Physical location, for example, may cause differing allele frequencies between the two populations.

Question 1.3

TZ2SwJ2OZF5yBGpR2ZW4x6+5JXwD024UjjaO8zJOkt8=
Actually, you could if you extracted all the DNA from a population—although it would be pretty viscous…

Relate evolution to gene pool and allele frequencies.

Question 1.4

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For evolution to occur, the frequency of alleles in a population’s gene pool must change.

Question 1.5

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A change in allele frequencies does not mean that a beneficial evolutionary change has happened. There may be shifts in allele frequencies that are neither beneficial nor harmful.

Review Questions

Question 1.6

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2
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Question 1.7

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2
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Question 1.8

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2
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1.3 Driving Question 2

Driving Question 2

How do different evolutionary mechanisms influence the composition of a gene pool?

Why should you care?

Different mechanisms of evolution, both positive and negative, can easily occur and act on a population at the same time. For example, a population could be experiencing a loss of genetic diversity through natural selection and, at the same time, gaining diversity through random mutation or gene flow. Humans, historically and presently, have a great effect on the evolution of different populations of organisms; unfortunately this effect is often negative. By knowing the different mechanisms of evolution, humans may be able to right some of these wrongs by introducing genetic diversity into endangered populations.

What should you know?

To fully answer this Driving Question, you should be able to:

  1. Compare and contrast the mechanisms of genetic drift.
  2. Propose how genetic diversity can be increased in populations and why that is beneficial.
  3. Compare and contrast adaptive and nonadaptive mechanisms of evolution.

Infographic Focus

The infographics most pertinent to the Driving Question are 15.3, 15.4 and 15.5 and Table 15.1.

Question Test Your Vocabulary

Choose the correct term for each of the following definitions:

Term Definition
D/8zWW6ycUDvs08lrhqwSWw5vHVR+88v/MYLAeu6EZwesEWBJ32AN3BUua//iHQSAWrdkL1cwRD0me+0D2w9wVVl+xn5l4IfuULTmaJKZPhjtA6LZrt0/qXZagUomluGDmGoLcESe1E3Idmtv07es9qsiELQOBEx The negative reproductive consequences for a population associated with having a high frequency of homozygous individuals possessing harmful recessive alleles.
z0LcEhJSxQrkqqbbs+jZkYHUKrP0ZE/N6B7PPGQLqEgM/+yjJp/CIh5eJbMnQ9fzARmh8uMlSBm9EPQXqVQypOWHZeHLZNXZvBbpS77iIrfyIenK6vhTb5EHJjdACiIdI5qdsKhxeif7NFZ8sVeo7Und1Eu6F/Zg A type of genetic drift in which a small number of individuals leaves one population and establishes a new population; by chance, the newly established population may have lower genetic diversity than the original population.
5xCEYw7GYbHalxV1usOCDBLt/Fon6+sblakBpgBC30flD9kkAyFGR5GAsmJfxyXj6jBwJ5S5QfL8Fby4HE4shEV+mOXea9TVDXDLUAaw5uuoww3ofmgQCtvQne7Hqbw6KzVjoxgFbTuChTcUJ0k3WsD1WVHbAo9T The movement of alleles from one population to another, which may increase the genetic diversity of a population.
PMg9cNQxfvsDCev3PdhEk1Y+I8iz2QSt6HQ51iOQZ9T7vfIzPZYO362iZKbHTXlBe+YQGSTYTxjXDr29kvEgNuai6+W0fFf/yHtQsdO1f1YMgf1g1rtu7upISJMtL8UyXs53L8M1197GpKAnugd8zO+DwTVTvxOZ Any change in allele frequency that does not by itself lead a population to become more adapted to its environment; the causes of nonadaptive evolution are mutation, genetic drift and gene flow.
iwATsDE6dTXF6hZLsRkPA+u1D8TRsjW0pRd8gg16+HtewvfveyMp0Ox9Pr1zQ7U+IkAzRjt+7tws9dNOkuyNFv9LZM0p+F+3bitsCvmh28psSf6wwmuHwKmmwVoo2KyXgbje4tCcFL3QaLTuqQbADnglcEqNvBaa A type of genetic drift that occurs when a population is suddenly reduced to a small number of individuals and alleles are lost from the population as a result.
n0PfFN0nNZL3x9wDFTYvuv9DnZN0qJmWF50NbUgmM34V3gCe97QFeDRaWmQUBu8oYULD8NZVQEV5XyhbeaKz8BoUHWbezfwpDHi5TV8iqzVProUOddCB1ujifhbSa4JWMrMAx/DTj+6lzgqvFpRs4XvJn5LTT5Xg Mating between closely related individuals. Inbreeding does not change the allele frequency within a population, but it does increase the proportion of homozygous individuals to heterozygotes.
qou/QCZ4mVHwdw9yZ+fleq/Or6AgwxtVPcm59Eah0Sc45YmKobSKeX8w6xyTWuVC6Z4vm5YMS/UU4mAgzb+vB3a69n87L2uho+h0YPtGv/mvy+/UpN9gRTRv5xS7Jo1C+ujkZC1anaODzPJKIm9cUR+BAxZ0zH4o Random changes in the allele frequencies of a population between generations; genetic drift tends to have more dramatic effects in smaller populations than in larger ones.
Table
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Compare and contrast the mechanisms of genetic drift.

Question 1.9

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Genetic drift is the change in allele frequencies from one generation to the next purely as a result of chance.

Question 1.10

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because all populations are affected by chance

Question 1.11

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The two mechanisms of genetic drift are the founder effect and the bottleneck effect.

Question 1.12

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They are similar in that a genetically diverse starting population becomes less diverse after drift. In each case, a few individuals end up starting a new population. They are also the same in that they are random and nonadaptive.
The founder effect and bottleneck effect describe different mechanisms of genetic drift. A founder effect happens when a few individuals migrate to found a new population, leaving the original population reasonably unchanged, while a bottleneck effect is the result of eliminating a large portion of the original population, leaving a few individuals to rebuild the population.

Question 1.13

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The effects of genetic drift are more severe for smaller populations because smaller populations are typically less genetically diverse. If you start with a homogeneous population and have a drift event, either a founder effect or a bottleneck effect, the population is likely have even less diversity after the drift. A population that does not have much genetic diversity may not be able to survive future events or selection presses as well, if at all, as a genetically diverse population.

Propose how genetic diversity can be increased in populations and why that is beneficial.

Question 1.14

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Genetic diversity can be increased in populations by gene flow. Gene flow results when individuals move from one population to another or mate with individuals from a different population, introducing new alleles to the receiving population. Increased genetic diversity is beneficial because the population is more likely to survive a selective or random event if it has many varieties of alleles and thus many phenotypes of individuals. For example, a virus that infects and kills individuals with a specific allele would cause more damage to a population most of whom had that allele than to a population whose gene pool was more varied.

Compare and contrast adaptive and nonadaptive mechanisms of evolution.

Question 1.15

Fill in the following table:

Mechanism of Evolution How allele frequencies change Adaptive or Nonadaptive? Its effect on genetic diversity
Natural Selection LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
Mutation LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
Genetic Drift LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
Gene Flow LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
A single mutation in a tumor suppressor gene associated with DNA repair.
LU/yM02nlYRE6AmYkP5/HeY78u0=
Correct.
Table
2
Mechanism of Evolution How allele frequencies change Adaptive or Nonadaptive? Its effect on genetic diversity
Natural Selection Alleles that favor the survival and reproduction of the individual become more common Adaptive, because the allele frequencies change in response to a selective pressure. Usually this decreases genetic diversity because the individuals who do not have the desirable trait may die or be unable to reproduce.
Mutation Random mutations produce new alleles. Nonadaptive because mutation is a random event. Increases; there are novel alleles in the population.
Genetic Drift Chance events, like the elimination of most of the population or the founding of a new population by a few individuals, lead to a change in allele frequencies. Nonadaptive, because these are chance events. Decreases; the diversity of the population is reduced.
Gene Flow The movement of individuals from one population to another causes new alleles to be introduced into the receiving population. Nonadaptive; it is random movement of individuals between populations. Increases; new alleles are brought into the population by the migrants.
Table
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Question 1.16

In the following scenarios, say what evolutionary mechanism is likely to occur and why:

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Genetic drift, specifically the founder effect, because a few individuals separated from the main population will now start a new one.

Question 1.17

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Natural selection, because the disease will kill any susceptible plants and leave those with alleles providing disease resistance.

Question 1.18

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Gene flow is likely to happen because the two populations are close enough to mate and reproduce with each other.

Question 1.19

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Genetic drift, specifically the bottleneck effect, because the population of beetles is reduced to a few members.

Question 1.20

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Since an error-prone RNA polymerase introduces mutations into the mRNA, the likely evolutionary mechanism for this population of viruses is mutation.

Review Questions

Question 1.21

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Question 1.22

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2
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Question 1.23

What would help a population with inbreeding depression? (Mark "true" all that apply.)

a. Antidepressants kn+fKbLB8wAnmZ3XQAUvWA==

b. Mutation 2YvaXR/y8mhoD5Q0hHYKqg==

c. Gene flow 2YvaXR/y8mhoD5Q0hHYKqg==

d. A selective pressure kn+fKbLB8wAnmZ3XQAUvWA==

Correct.
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1.4 Driving Question 3

Driving Question 3

How does the gene pool of an evolving population compare to the gene pool of a nonevolving population?

Why should you care?

In early 1908, two mathematicians (G. H. Hardy and Wilhelm Weinberg) independently published their findings that genotype frequencies will not change in large, randomly mating populations in which mutation, migration, and natural selection are absent. Remember that when genotype frequencies (and their underlying allele frequencies) don’t change, no evolution is occurring. The Hardy-Weinberg principle, then, specifies conditions under which evolution will not take place, or rather it is a null hypothesis that defines conditions where genotype frequencies are not changing (i.e. in a hypothetical nonevolving population). It also provides a very useful tool with which to determine whether or not evolution is taking place in a population and, if so, how extensively.

What should you know?

To fully answer this Driving Question, you should be able to:

  1. List and describe the conditions under which a theoretical population will be in Hardy-Weinberg equilibrium.
  2. Explain the relationship between evolution and Hardy-Weinberg equilibrium.
  3. Discuss whether or not the Hardy-Weinberg conditions are likely to occur in natural populations and explain what that means in terms of evolution.
  4. Given the frequency of one allele, be able to calculate the allele and genotype frequencies of a trait controlled by two alleles in a nonevolving population using the Hardy-Weinberg equation.

Infographic Focus

The infographics most pertinent to the Driving Question are 15.5, Up Close: Calculating Hardy-Weinberg Equilibrium and Up Close: The Hardy-Weinberg Equation.

Question Test Your Vocabulary

Choose the correct term for each of the following definitions:

Term Definition
B/mS+ggDINcUWpiz01+Y6tREJt/y5opndV1WHLc+LwREXEMnttErKNA8pUVtJpDu745ivXXJUYA= A mathematical formula that calculates the frequency of genotypes and phenotypes one would expect to find in a nonevolving population.
+86sBXmUdqz7FA23uswwGn1xhcyOQZUOnKth4WBh7wRBtZ5Ld/Btz8T+KzRxw0laQikfVd6enp4= The principle that, in a nonevolving population, both allele and genotype frequencies remain constant from one generation to the next.
Table
9
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List and describe the conditions under which a theoretical population will be in Hardy-Weinberg equilibrium.

Question 1.24

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The five conditions necessary for a population to be in Hardy-Weinberg equilibrium:
1. No mutations occur: new alleles are not introduced into the population.
2. No natural selection occurs: no selective pressure changes the allele frequency.
3. The population is infinitely large (no genetic drift): the population cannot be reduced to yield a lower genetic diversity.
4. No gene flow: new alleles are not introduced into the population.
5. Mating between individuals is random: there is no selective pressure favoring mating between individuals and thus no favor for specific alleles over others.

Explain the relationship between evolution and Hardy-Weinberg equilibrium.

Question 1.25

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No, a natural population can never be in Hardy-Weinberg equilibrium because no population found in nature will ever have all of these conditions. There will never be an—infinitely large population with no mutation, no mating preference, and no natural selection. At a given time, it is possible that one or more of these conditions would apply to a natural population, but this population will change, and at no point would all of the conditions apply to a natural population.

Discuss whether the Hardy-Weinberg conditions are likely to occur in natural populations, and explain what that means in terms of evolution.

Question 1.26

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1. No mutations occur: this is unlikely because DNA and RNA polymerase do have an error rate, albeit a low one.
2. No natural selection occurs: this is unlikely because the environment is continually changing. Pathogens also evolve, which is another source of selective pressures.
3. The population is infinitely large (no genetic drift): no population is that large.
4. No gene flow: this could happen as a result of isolation of a population.
5. Mating between individuals is random: this is unlikely because organisms put a lot of effort (metabolically and physically) into mate attraction and selection. They want to mate with an individual whose alleles will give their offspring the best chance of survival; this is not random.

Question 1.27

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Evolution is likely to be a common process because many factors, both positive and negative, affect allele frequencies of a population.

Given the frequency of one allele, calculate the allele and genotype frequencies of a trait controlled by two alleles in a nonevolving population using the Hardy-Weinberg equation.

Question 1.28

Eye color in Jabberwocks is controlled by a single gene with two alleles that exhibit simple dominance. Flame eyes (F) are dominant to brown eyes (f), with individuals of Ff genotype having flame eyes. In a population of 500 Jabberwocks, 300 have brown eyes; the rest have flame eyes. The population is in Hardy-Weinberg equilibrium. Let p represent the frequency of the dominant allele and q represent the frequency of the recessive allele.

The Hardy-Weinberg equation is
p2 + 2pq + q2 = 1
p + q = 1

K0ot8AOw2m5El2bwmqbasnNIpnXi77FkcFqVhXlgSNtkouLqwUt7RgybvIqRvOSKt3drKYFbuJnZYfRRMoIEwg==
There are 1,000 alleles for the trait in the population, two alleles per trait times 500 instances of the trait.

Question 1.29

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The frequency of having brown eyes (ff) is 600 / 1,000 (ff alleles / total alleles) = 0.6.
This substitues q2 in the equation, so q2 = 0.6, or 60%.
Now we can figure out q. If q2 = 0.6, then √q = √0.6 = 0.77, or 77%.

Question 1.30

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If p + q = 1, then p + 0.77 = 1, so p = 1 - 0.77 = 0.23 or 23%.

Question 1.31

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The homozygous dominant individuals would be p2 so 0.232 = 0.05, or 5%.

Question 1.32

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If p2 + 2pq + q2 = 1, then 2pq = 2(0.23)(0.77) = 0.35, or 35%.

Question 1.33

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From the problem, brown eyes = 0.6 or 60%.

Check: p2 + 2pq + q2 = 1
0.232 + 2(0.23)(0.77) + 0.772 = 1

Review Questions

Question 1.34

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2
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Question 1.35

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2
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1.5 Driving Question 4

Driving Question 4

How do new species arise and how can we recognize them?

Why should you care?

Reproductive isolation is the hallmark of a species: two groups of populations that are reproductively isolated from one another (i.e., cannot interbreed with one another) are different species according to the biological species definition. When populations become reproductively isolated, each set of populations will accumulate genetic changes independently of the other. These changes will arise because of natural selection, genetic drift, gene flow, and mutation.

Whether or not a group of populations represents a distinct species is not only an important question for ecologists and evolutionary biologists, but for conservation biologists and government scientists as well. This is because the Endangered Species Act, our most potent set of laws and regulations promoting the conservation of biological diversity, focuses on species and subspecies.

What should you know?

To fully answer this Driving Question, you should be able to:

  1. List and describe the mechanisms that can reproductively isolate species and prevent them from interbreeding.
  2. Explain speciation and how it might benefit and, conversely, harm a population.

Infographic Focus

The infographics most pertinent to the Driving Question are 15.6 and 15.7.

Question Test Your Vocabulary

Choose the correct term for each of the following definitions:

Term Definition
Xk9DupST8ZXNmk9i7/tBVrSgRYehpUN/kOJy/acaE2iOQ67s+w04+6jMs97QtlJxV8hsq/MiXbUIoX4UXkCLHIYec6o= The genetic divergence of populations, leading over time to reproductive isolation and the formation of new species.
p7cjOU+Aei/+pQ4vbfQ4gY1q+C1IvcbYd80De1berjE1RgpCsCoet7oK4mZJZ7DMA4qew7DRikqWeVUMDFUq20k7868= The definition of a species as a population whose members can interbreed to produce fertile offspring.
TdkIXEkJjZ9Cm/UDhlNcUqDjkmA9ULP5U5YMRH/39SYU4kR3z+8ij6xalYKKlE893xiYvQmrBYRoeiBHuKky+Q+JoRE= Mechanisms that prevent mating (and therefore gene flow) between members of different species.
Table
9
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List and describe the mechanisms that can reproductively isolate species and prevent them from interbreeding.

Question Test Your Vocabulary

Choose the correct term for each of the following definitions:

Term Definition
pqInP3Wh2D2RCyKkD27hiRk2Rj3vQnrhRm8N7O1PKLFDOXsvGfYurMoqfHti2cRkAlDn92JnJPTxJl7uNKxFtZdNDDVGMAF2wBaTPqPO03abKHxr7P9yZFaD5hrUg8gUYgRfxuQkxq4CRzxO2i23bC/pWSMBNljy2eY8irOJPGe599T+73iBIGXkrCIuSaLZ Viable hybrid offspring cannot reproduce.
+wCiaOLn7SjlhBY0WOAuJeqZZqwUo4553X5Qrad6W483nd8wL/cCjH8ZBNvU+J/R1miq14xqyT+zGm4YETlndI8vc6uV6xoF1KDYjkAz/m9vnQkiP53LsXGqAGqSyX4sPRdtsEPrQnLSOc4iaK7LRWALKGtaFwy+IMso8Vj+rzo+yQg7dsxjHo47mg0d7UcE Mating behavior or fertility at different times.
aKDFndOBvzIGGVv+h57123UL2jJuv9KD0hGp8MPm7EGRxXv6ZHwiyYtaJEZi27xo2SAK9VriZ5bHnY8Vqb0ZlO0qhOaWyg15lEPi45aqdZ02wDHz8gmfmPlrVk8lEaIIp4zUL7rO8YS0oU4eEY0Q3XltqjtC1cPkN4ooOuc+iJ9dW7eEOTlcZrMLzpuBhYe8 Gametes unite but viable offspring cannot form.
IMk8FbMvGfkYpmGtetQaJ54VK/Taj0AzGA7YFVJd9sspForJaISWU6ay1EIiZVspEUQx9n8YIQHSFZSV/uk5P6c1QB5FVdpx5t1kWjWLF9ZsEc7Xco5gQ7CGEAv5yFJF/Cs3uqxalMGnut/B64ypCgZCNlrvPdcneuJKC+UU8J57rdQZPss0xxLdqvR0QCWi Different environments.
nZw6+5Gh0/NBHoO7ickm8NrPituF61Uj8uSf9xCdnpWwSNfVkxfmaKO0+rwZj9w91p8xrifTWeDINKxalq1CgmFaGJ96AJT1pMSlwH7SIY32JmRtqgENy8hxcKHgo4zCKZS8xY2HfgjRZVDN0xxiCvrIu8nApfWxWI0Q0+8sgquEDR+dpZBrKs7GiLEeE/JQ Mating organs are incompatible.
GY7gG1E8MhcETthpla3UXquyHQ7U8kyawkC057oJxAGWBV6bJ9ExaVXIHUt2N9jKGeJQKbCVyyVtcOF5LTn6kUpYQuve2waLYttsSbz3GSiJoqxHZtjQe2+lMifsvWPd9laS50KNtl1wU4/9IshJh0dqpW9CDeb1/w2X2aoYLluexOszC+Xhs9vQvGkQGC63 Gametes cannot unite.
vNDjPuQCuI7rWbZuoo6lBfE/HX+RJdpIX40hqXtKZ+50ptgSa9/1b9+SZamVZZdt7kIlM2KHt2aoyfVW5jCmm6nirqDA2hdRNQTbV0NDeJf3pyqn8tqw/+gbqHMOlEcXLzVsg6npfS+8yHy2V8Ibdxk63+yv1AsV+aFtjve14oW6abM0dNg2l7C9qkaq4ki6 Different mating activities.
Table
2
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Explain speciation and how it might benefit or harm a population.

Question 1.36

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Speciation occurs when two populations of a species become genetically different enough that they no longer are able to mate and produce fertile offspring.

Question 1.37

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A potential benefit of speciation is that the two populations may no longer be in competition for the same food source or habitat area. They may have become genetically different enough that one population is able to utilize a different food source. A potential drawback of speciation is that there would no longer be gene flow between the populations, which would eliminate a source of genetic diversity.

Review Questions

Question 1.38

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2
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Question 1.39

2R+UUMvK4EQZQhr8uQINJpci7QBDRdg1v/maj88oA09772fsuGWmHpQ6Iok6mjNbtVkTC4GOV3rMJCuHqYFir1ttJu5E/tUP8/vIbJDXtu1qFDAWu1/0nEifvK/aRiPObyFcqs7yQoNt1p6uRxFyfXZEnQoUSMYpuouZ+09BtxGUr5jxUJTny7sLprihCucoDDusA/2LWKJTYC+4HzQ+KZvqu+BKmUhQODzUdLHfh8Io2u90xLH58bibrgqlu9vbKwocQxOBSR8qkG6fl4k2VFTkOAT/qIjBztLjjnbsk7deOAfD0bY2m9SWinKaubAPg2Zz8bstDozV3jmx6rBfrjzt34Bs0C7w3BbiHXbpmhB3+2WSF9PZqtOh6zR0C2izBeQfKH9toDU=
2
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Correct.
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