Connect BIOL CHAP 23

Why are the terms 'natural selection' and 'evolution' not synonymous? -Because evolution occurs in populations, not in individuals, while natural selection can act on individuals. -Because evolution can only change genotype frequencies while natural selection can only change allele frequencies. -Because natural selection is only one of many mechanisms that lead to evolution. -Because evolution operates on a genetic level while selection acts upon a phenotypic level.

-Because evolution occurs in populations, not in individuals, while natural selection can act on individuals. -Because natural selection is only one of many mechanisms that lead to evolution. -Because evolution operates on a genetic level while selection acts upon a phenotypic level.

The figure above depicts two deer populations that occasionally interbreed. What evolutionary mechanism is shown and what statement best describes its consequences? -directional selection. Due to interbreeding between the two populations, both will experience a loss of genetic diversity over time. -inbreeding - Due to interbreeding between the two populations, the proportion of homozygotes in both will increase over time. -cryptic sexual selection - Due to interbreeding between the two populations, their allele frequencies will become more similar over time. -gene flow - Due to interbreeding between the two populations, the genetic diversity in both will increase over time.

-gene flow - Due to interbreeding between the two populations, the genetic diversity in both will increase over time.

Which finches survived to reproduce? -those able to eat the larger seeds -those able to survive with less water -those able to swim -those able to fly to neighboring islands for food

-those able to eat the larger seeds

How might natural selection have resulted in frogs that prefer to lay their eggs on an overhanging leaf rather than in the water? Multiple Choice 1. Frogs that laid their eggs on overhanging leaves had higher reproductive success than frogs that laid their eggs in the water, and this trait spread through the population. 2. Frogs that laid their eggs on overhanging leaves had higher survival rates than frogs that laid their eggs in the water, and this trait spread through the population. 3. Frogs noticed predators eating their eggs in the water, so they began to lay their eggs on overhanging leaves. 4. All frogs lay their eggs on overhanging leaves, because they spend their whole lives in the canopy.

1. Frogs that laid their eggs on overhanging leaves had higher reproductive success than frogs that laid their eggs in the water, and this trait spread through the population. Correct

Consider a population of birds with three color morphs, each with a different genotype. Red birds leave 10 offspring in the next generation, orange birds leave 8 offspring, and yellow birds leave 2 offspring. Based on this information, indicate whether the following statements are true or false. a. The relative fitness of red birds is 0.5. b. The relative fitness of yellow birds is 0.2. c. The difference in fitness between red and orange birds is 0.1. d. The difference in fitness between orange birds and yellow birds is 0.6. e. Natural selection would favor red birds over yellow birds.

1. The relative fitness of red birds is 0.5. false 2. The relative fitness of orange birds is 0.2. TRUE 3. The difference in fitness between red and reddish orange birds is 0.1. FALSE 4. The difference in fitness between reddish orange birds and orange birds is 0.6. TRUE 5. Natural selection would favor red birds over orange birds. TRUE

A gene pool consists of 1. all alleles for all genes in a population. 2. the dominant alleles for all genes in a population. 3. all alleles for genes related to reproductive success in a population. 4. all alleles for genes of reproductively mature individuals only.

1. all alleles for all genes in a population.

What advantage do frog eggs that were laid in trees have over frog eggs that were laid in jungle pools? 1. increased exposure to water 2. decreased predation 3. increased exposure to sunlight 4. decreased incidence of disease

2. decreased predation

How does inbreeding depression decrease a population's fitness? 1. Inbreeding directly increases the frequency of harmful recessive alleles, fixing them in the population. 2. Inbreeding increases the frequency of homozygotes, which are always less fit than heterozygotes. 3. Inbreeding can increase the frequency of homozygotes for harmful recessive alleles. 4. Inbreeding increases the frequency of heterozygotes, which can be less fit than homozygotes.

3. Inbreeding can increase the frequency of homozygotes for harmful recessive alleles.

Identify whether the following evolutionary mechanisms result in changes in allele and genotype frequencies or result in changes in the balance of genotypes. Assortative Mating Inbreeding Genetic Drift Gene Flow

Changes allele and genotype frequencies Genetic Drift Gene Flow Changes the Balance of genotypes Assortative Mating Inbreeding

Directional Selection

Dark Fur Light Fur

Diversifying Selection

Dark Fur on one island and light fur on another island Dark Fur in forests and light fur in fields

Sexual selection can increase the prevalence of phenotypes that have a relatively lower chance of survival True or False

FALSE

Stabilizing Selection

Grey Fur

Habitat fragmentation is a big concern to conservation biologists. How will habitat fragmentation effect evolution by genetic drift? Multiple Choice 1. Habitat fragmentation will reduce the effect of genetic drift, and lead to an increase in variation. 2. Habitat fragmentation will reduce the effect of genetic drift, and lead to an decrease in variation. 3. Habitat fragmentation will increase the effect of genetic drift, and lead to an increase in variation. 4. Habitat fragmentation will increase the effect of genetic drift, and lead to an decrease in variation. 5. Habitat fragmentation will have no effect on genetic drift. The same amount of genetic drift will occur whether or not a habitat has been fragmented.

Habitat fragmentation will increase the effect of genetic drift, and lead to an decrease in variation.

Sexual selection results in nonrandom mating. Indicate which type of sexual selection is being exhibited in these examples.

Intersexual: Nest building of male Gilded Flicker, Mating of Male Bullfrog, Long Tail of male peacock. Intrasexual: Large claws in male lobsters, Sparring ability of male kangaroos. Both: Strength and antler size of male elk

As the snake slithers away, what does it do with its tail? Multiple Choice It protects it by bending it under its midsection. It causes it to strike out defensively like the head of a snake in retreat. It breaks its tail off at the tip to delay a predator in pursuit. It whips its tail violently back and forth to injure pursuing predators.

It causes it to strike out defensively like the head of a snake in retreat. Correct

Rank the following mice (house mouse, Mus musculus) from greatest reproductive success (rank 1) to least reproductive success (rank 5) over the course of their lifetime. Assume all individuals reach reproductive maturity at 4 weeks

Rank the options below. 5. Mouse A (Lifespan = 1 year, 10 litters per year, 1 fertile offspring per litter) Mouse A (Lifespan = 1 year, 10 litters per year, 1 fertile offspring per litter) 3. Mouse D (Lifespan = 1 year, 6 litters per year, 3 fertile offspring per litter) Mouse D (Lifespan = 1 year, 6 litters per year, 3 fertile offspring per litter) 2. Mouse E (Lifespan = 2 years, 5 litters per year, 3 fertile offspring per litter) Mouse E (Lifespan = 2 years, 5 litters per year, 3 fertile offspring per litter) 1. Mouse B (Lifespan = 2 years, 8 litters per year, 2 fertile offspring per litter) Mouse B (Lifespan = 2 years, 8 litters per year, 2 fertile offspring per litter) 4. Mouse C (Lifespan = 3 years, 5 litters per year, 1 fertile offspring per litter)

Use terms associated with genetic drift and selection Complete the sentences with the correct terms.

The random change in allele frequencies is called genetic drift. Genetic drift can lead to the fixation of an allele and occurs rapidly in small populations. When populations are reduced following a major disaster the resulting random change in allele frequencies is called the bottleneck effect. If the population returns to its pre-disturbance size, genetic variation is generally lower than in the original population. When a few individuals colonize a new location, the subsequent random change in allele frequencies is called the founder effect.

In a population of 100 four o'clock plants, there are 50 red-flowered plants with genotype CRCR, 30 pink-flowered plants with genotype CRCW, and 20 white-flowered plants with genotype CWCW. Match the correct frequencies for the following alleles and genotypes. a. CRCR b. CRCW c. CWCW d. CR e. CW

a. CRCR 0.5 Correct b. CRCW 0.3 Correct c. CWCW 0.2 Correct d. CR 0.65 Correct e. CW 0.35 Correct

Determine whether the following statements are consistent with Motoo Kimura's neutral theory of evolution. a. Most of the genetic variation in a population is due to neutral mutations. b. Neutral mutations do not alter evolutionary fitness. c. Neutral mutations can spread throughout a population via natural selection. d. Neutral mutations are subject to sexual selection. e. The neutral theory of evolution explains adaptive changes in a species during evolution. f. The neutral theory of evolution contradicts Darwinian evolution.

a. Most of the genetic variation in a population is due to neutral mutations. TRUE b. Neutral mutations do not alter evolutionary fitness. TRUE c. Neutral mutations can spread throughout a population via natural selection. FALSE d. Neutral mutations are subject to sexual selection. FALSE e. The neutral theory of evolution explains adaptive changes in a species during evolution. FALSE f. The neutral theory of evolution contradicts Darwinian evolution. FALSE

A wildfire dramatically reduces a population of oak trees. Several months later, high winds blow several acorns from the surviving oak trees to a meadow several hundred miles away. The acorns germinate and establish a new population of oaks in the meadow. The surviving oaks in the original population will likely experience a ______ effect, while the oaks in the new population will like experience a ______ effect.

bottleneck, founder

All individuals in a population of birds are tagged and measured. The beaks of the birds vary in size from small to large. These data provide evidence for which requirement of natural selection? Check All That Apply individual variation inheritance overproduction differential reproductive success

individual variation