Chapter 20

In the video, what happened to some of the tadpoles that fed upon large quantities of fairy shrimp? They became strict herbivores. They became calmer and gentler. They became cannibals. They died from toxins in the shrimp.

They became cannibals.

A major mechanism of speciation in plants but not in animals is?

polyploidy

Adaptive radiation

single species evolves into array of descendents that differ greatly in habitat, form or behavior

When the tadpoles in the video mature, they will become ______.

spadefoot toads

What would be an example of allopatric speciation

A few birds fly to a distant island and after many generations a new bird species is formed

Species

A group of organisms that maintains a distinctive set of attributes in nature

A large number of honeycreeper species on the hawaiian islands is an example of?

Adaptive radiation

Emphasizes reproductive isolation

Biological species concept

Macroevolution

Evolutionary changes that create new species and groups of species

Sympatric speciation

Occurs when members of a species that are within the same range diverge into two or more different species even though there are no physical barriers to interbreeding

BMP4

causes cells to undergo apoptosis and die

Species contain members that can interbreed with one another to produce viable, fertile offspring

Biological species concept

True or false: injecting BMP4 into the interdigital regions of a developing chicken foot produces a webbed foot. True False

False

Heterochronic mutations __________. a. Alter the expression of a pseudogene b. Have little observable effects c. Change the spatial pattern of gene expression d. Change the timing of a developmental stage e. Are always beneficial to the organism

10. D

Cell differentiation occurs when __________. a. A zygote is formed b. Cells begin to divide c. A cell undergoes apoptosis d. The cell is committed to becoming a certain type e. A cell's morphology and function have changed into a specialized type

10. E

What is paedomorphosis? a. The retention of juvenile characteristics in the adult organism b. A change in the number of copies of the genome in a cell c. A form of hybrid sterility d. The results of many generations of consistent inbreeding e. None of the above

11. A

In a human embryo, limb buds grow by mitosis and cells differentiate to form the different tissue types in the limb. The digits at the ends of the limb separate from each other via __________. a. Cell mitosis b. Cell commitment c. Cell migration d. Cell apoptosis e. None of the above

11. D

Genes such as HoxA and HoxB code for transcription factors. Changes in the expression of these genes __________. a. Changes the amino acid sequence of other genes b. Forms new genes c. Effects the timing and expression of other genes d. Causes mutations to arise e. Prevents changes in other genes

3. C

The lock and key fit of a dragonfly sex organ is an example of __________. a. Habitat isolation b. Temporal isolation c. Behavioral isolation d. Mechanical isolation e. Thermal isolation

3. D

Groups of actively dividing plant cells are called __________. a. Xylem cells b. Meristematic cells c. Schlerenchyma cells d. Casparian cells e. Nodular cells

4. B

The idea that reproductively isolated populations slowly accumulate differences until speciation occurs is called __________. a. Reverse selection b. Punctuated equilibrium c. Adaptive radiation d. Gradualism e. Mass extinction

4. D

The idea that speciation occurs in rapid bursts followed by long periods without change in species is called __________. a. Reverse selection b. Punctuated equilibrium c. Adaptive radiation d. Gradualism e. Mass extinction

5. B

Hematopoietic stem cells are found in __________. a. Brain tissue b. Lever tissue c. Bone marrow d. Epithelial tissues e. Only in embryonic tissues

5. C

A cell that can become any other type of cell is __________. a. Unipotent b. Multipotent c. Pleuripotent d. Totipotent e. Impotent

6. D

Geographic isolation is a key component of __________ speciation. a. Sympatric b. Parapatric c. Monophyletic d. Allopatric e. Homeopathic

6. D

What are stem cells? a. Cells fated to develop into a certain type of cell b. Undifferentiated pleuripotent cells c. Cells with inactive Hox genes d. Cells that determine the body plan of the organism e. Unipotent cells

7. B

Closely related species that have different mating rituals are an example of __________. a. Ecological isolation b. Temporal isolation c. Behavioral isolation d. Mechanical isolation e. Thermal isolation

7. C

The colinearity rule states that the order of the homeotic genes along the chromosome correlates with the expression of those genes along the anteroposterior axis of the body. a. This is true b. This is false

8. A (True)

Polyploidy occurs when __________. a. Individuals have more than 2 sets of chromosomes. b. A replication error causes a species to have double the normal number of chromosomes. c. A hybrid has both sets of chromosomes from its parents. d. A species is quadroploid, hexaploid, or octoploid. e. All of the above

8. E

There are about 1.4-1.8 million described species; this is a relatively complete list and the total number of species on Earth is estimated to be at most 3 million species. a. This is true b. This is false

9. B (False)

A chemical that is used to communicate positional information during the course of development is a/an __________. a. Chemokine b. Epitope c. Homeolog d. Facilitator e. Morphogen

9. E

Determine whether the examples are most likely to undergo allopatric or sympatric speciation. sympatric speciation

A plant species in wet and dry soils an insect species that can feed on different plant species a plant producing polyploid offspring

A mechanism of reproductive isolation that does not prevent fertilization from happening is called?

A postzygotic isolating mechanism

What began the adaptive radiation process for finches on the Galapagos islands? Genetic drift caused random changes that led to the adaptive radiation. As finches migrated from different islands, they brought unique characteristics with them. As one food source became scare, those finches who could eat other foods thrived. Two different species of finches mated and gave rise to a hybrid finch capable of eating different food.

As one food source became scare, those finches who could eat other foods thrived.

Sexual selection

Certain females prefer males with one color pattern, while other females prefer males with a different color pattern

Evo-Devo: Evolutionary Developmental Biology

Compares the development of different organisms to understand: Ancestral relationships between organisms Developmental mechanisms that bring about evolutionary change Involves the discovery of genes that control development, and how their roles vary in different species

Cladogenesis

Division of a species into two or more species Requires gene flow between populations to be interrupted

Ecological species concept

Each species occupies an ecological niche - the unique set of habitat resources that a species requires, as well as its influence on the environment and other species

Adaptation to local environments

Geographic area may have variation so that some members of a population may diverge and occupy different local environments that are continuous with each other

Three lines of evidence support Hox Genes

Hox genes are known to control fate of regions along the anteroposterior axis General trend for more complex animals to have more Hox genes and Hox clusters Comparison of Hox gene evolution and animal evolution bear striking parallels

Four main problems for determining species

May be difficult to determine in nature Can interbreed and yet do not Does not apply to asexual species Cannot be applied to extinct species

Allopatric speciation

Most prevalent method for cladogenesis Occurs when some members of a species become geographically separated

Polyploidy

Organism has two or more sets of chromosomes Plants more tolerant of polyploidy than animals Can occur through nondisjunction (autoploidy) Alloploids contain chromosomes from two or more different species

Morphological traits

Physical characteristics of an organism Drawbacks for determining species How many traits to consider Traits may vary in a continuous way What degree of dissimilarity to use Members of the same species can look very different Members of different species can look very similar

Mechanisms of Sympatric speciation

Polyploidy Adaptation to local environments Sexual selection

Biological species concept

Species is a group of individuals whose members have the potential to interbreed with one another in nature to produce viable, fertile offspring But cannot successfully interbreed with members of other species

Evolutionary lineage concept

Species should be defined based on the separate evolution of lineages

Place each example into the corresponding characteristic used to distinguish species. Morphological traits

# of stamens in a flower

What is it called when two species maintain reproductive isolation by using different components of a habitat (e.g. toads breeding in ponds vs. toads breeding in streams)? a. Habitat isolation b. Temporal isolation c. Behavioral isolation d. Mechanical isolation e. Thermal isolation

1. A

The organism Arabidopsis thaliana has been extensively studied and used as a model organism to study the genetics of __________. a. Invertebrate animals b. Vascular plants c. Unicellular fungi d. Mammalian species e. Pathogenic bacteria

1. B

What is an example of post zygotic isolating mechanism?

Fertilized eggs fails to develop normally

Gametic Isolation

Gametic transfer takes place, but the gametes fail to unite

Each species is a population of an independently evolving lineage

General lineage concept

Determine whether the reproductive isolating mechanisms are prezygotic or post zygotic. Prezygotic

Habitat isolation temporal isolation behavioral isolation Mechanical Isolation

Determine whether the reproductive isolating mechanisms are prezygotic or post zygotic. post zygotic

Hybrid inviability hybrid sterility hybrid breakdown

Hybrid Inviability

Th egg of one species is fertilized by sperm from another species, but the fertilized egg fails to develop

he adaptive radiation of cichlids allows us to predict what about the original population of cichlids in Lake Tanganyika? There was variation in the shape and size of teeth in the original population. As Lake Tanganyika grew, more fish species could evolve to fill the lake. There was a very small number of individuals in the original population. Individuals of the original population ate many different kinds of food.

There was variation in the shape and size of teeth in the original population.

Molecular features

compare features to identify similarities and differences among different populations DNA sequences within genes Gene order along chromosomes Chromosome structure Chromosome number

Place each example into the corresponding characteristic used to distinguish species. Reproductive isolation

compatibility of surface proteins on Egg and sperm

Which of the following species would you expect to have the most number of hox genes? a. nematode worm b. fruit fly c. bird d. mammal e. all of the above

d. mammal

When dry conditions began causing the puddle to dry up, the fairy shrimp appeared. Where had the fairy shrimp been? dormant underground on plants above the pool in a neighboring pool in digestive tracts of the tadpoles

dormant underground

Which of the following would be the most likely to promote an abrupt speciation event a. the formation of a new species on an island b. the adaptation of a species to local environments c. the formation of a polyploid species from a single diploid species d. the formation of an allotetroid from two diploid species e. both c and d

e. both c and d

Micro evolution

evolution on a small scale as it relates to allele frequencies in a population

Heterochrony

evolutionary changes in the rate or timing of developmental events Compare head growth between human and chimpanzee

A dam dividing a fish population could lead to sympatric speciation.

false

Darwin believed that the finch beaks evolved to accommodate their different feeding habits. If the finches had lived in different habitats (beach, forest, etc.), what different characteristic might have evolved? feather coloration beaks size leg length

feather coloration

Hox genes

found in all animals Variation in the Hox genes may have spawned the formation of many new body plans Number and arrangement of Hox genes varies among different types of animals Increases in the number of Hox genes may have led to greater complexity in body structure

A mutation arises in a Paramecium that turns off the gene that inhibits cilia growth. Paramecium with this mutation end up with very long cilia relative their body (cell) length. This type of change is called polyploidy homeotic anagenesis heterochrony

heterochrony

Gremlin

inhibits the function of BMP4 and allows cell to survive

A long, thin, probing beak enables finches to feed on what food source? plants insects seeds small fish

insects

hybrid breakdown occurs when?

interspecies hybrids are fertile but produce offspring with reduced viability and infertility

According to de Queirozs general lineage concept, each species?

is a population of an independently evolving lineage

Place each example into the corresponding characteristic used to distinguish species. Molecular features

mRNA sequeneces in ameoba

Natural selection

may rapidly alter the genetic composition of the population, leading to adaptation to the new environment

Mechanical Isolation

morphological features such as size and incompatible genitalia prevent 2 members of different species from interbreeding

Commonly used characteristics for identifying species

morphological traits, ability to interbreed, molecular features, ecological factors, and evolutionary relationships

Speciation

occurs due to the accumulation of microevolutionary changes, those that occur in single genes

Place each example into the corresponding characteristic used to distinguish species. Ecological factors

portion of tree used for nesting salinity tolerance in salt marsh

A thick, crushing beak enables finches to feed on what food source? insects seeds small fish plants

seeds

Specialization on different plant hosts for members of an insect population can lead to sympatric speciation.

true

Interspecies hybrid

when two species do produce offspring

How many different species of cichlids are present in Lake Tanganyika? 1 10 200 2000

200

The gene product of the bicoid gene is a transcription factor that activates genes based on its concentration. The end of the animal with the highest concentration becomes that anterior end and the end with the lower concentration becomes the posterior end of the animal. What would happen if the bicoid gene was inoperative? a. Formation of 2 anterior ends b. Normal development c. Formation of 2 posterior ends d. The pattern would be flipped from normal e. None of the above

12. C

The vast numbers of finch species on the Galapagos Islands are very closely related and differ primarily by feeding specializations. What process best explains this distribution of species? a. Mass extinction b. Allopatric speciation c. Hardy-Weinberg equilibrium d. Adaptive radiation e. Polyploidy

12. D

The hybrid sterility of a hinny (a cross between a female horse and a male donkey) is an example of a pre- zygotic isolation mechanism. a. This is true b. This is false

13. B (False)

Lymphomas are cancers of the white blood cells (the lymphocytes). These are often treated with high doses of chemotherapy and/or radiation to kill the abnormal cells. Bone marrow transplants are often performed after these procedures. What is the purpose of the transplant? a. To remove the debris from the dead cancer cells b. To allow for the body's hematopoietic cells to regenerate c. To replenish the body's supply of hematopoietic stem cells d. To surgically remove cancer cells e. None of the above

13. C

Domestic wheat (Triticum aestivum) evolved as a result of two successive polyploidy events. These events resulted in the combination of the genes of three (3) separate diploid species. What type of polyploidy is wheat? a. Triploid b. Quadroploid c. Hexaploid d. Octoploid e. Dodecaploid

14. C

Mutations in the HoxD13 gene have been linked to synpolydactyly, a disease where an affected person has multiple fused fingers and toes. What is the function of HoxD13? a. Determining the anteroposterior axis of the body b. Coordinating segmentation of the embryo c. Inducing cell differentiation d. Activating genes that direct morphogenesis of the digits e. Forming bone tissue

14. D

The scarecrow gene in plants is responsible for inducing the asymmetric mitosis that gives the root its internal structure. What would happen if this gene were defective? a. The roots would not be formed. b. The roots would be normal. c. The roots would be missing some of the internal layers. d. The roots would be abnormally long. e. The roots would be photosynthetic.

15. C

Which of the following examples would lead to allopatric speciation? a. The colonization of an island by a small subset of a mainland population b. A new river channel dividing a population of beetles into separate populations c. The extinction of a large proportion of a population leaving only distant sub- populations d. A lava flow flowing across the landscape that isolates one population from conspecifics e. All of the above

15. E

As certain lineages of animals evolved more and more complex body plans, what has happened to the Hox genes of these animals? a. The number of Hox genes has been reduced. b. The more complex the body plan the greater the number of Hox genes. c. Complex body plans have more inactive Hox genes. d. Radially symmetrical animals have more Hox genes than bilaterally symmetrical animals. e. There is no correlation between Hox genes and body plan complexity.

16. B

Experimentally introducing the mouse Pax6 gene into fruit fly eyes produces eyes on the leg. The eyes that are induced by the mouse gene are compounds eyes. This demonstrates that __________. a. Mice and flies have the same type of eyes b. The genes for the development of eyes in mice and flies are the same c. The genetic switch that activates eye development genes is the same in mice and flies d. The mouse gene must mutate before it works in a fly e. There is no relationship between eye development in flies and mice

17. C

Homeotic mutations __________. a. Alter the expression of a pseudogene b. Have little observable effects c. Change the spatial pattern of gene expression d. Change the timing of a developmental stage e. Are always beneficial to the organism

2. C

The __________ species concept defines a species as a group of reproductively isolated individuals that are capable of interbreeding and producing viable offspring. a. Ecological b. Evolutionary c. Phylogenetic d. Biological e. Cladogenic

2. D

Which of the following statements best defines the term "adaptive radiation"? There are changes in habitat, timing, or behavior that prevent the mating of two different organisms. Speciation occurs through changes in chromosome number resulting in reproductive isolation. Some members of a species occupy a habitat that is isolated from other members of the same species. A single ancestral species evolves into a wide array of descendant species that differ in their habitat, form, or behavior.

A single ancestral species evolves into a wide array of descendant species that differ in their habitat, form, or behavior.

Hybrid sterility

An interspecies hybrid survives, but it is sterile

Postzygotic barriers

Block development of viable, fertile individuals Less common in nature because they are more costly in terms of energy and resources used HYbrid inviability hybrid sterility hybrid breakdown

Sympatric speciation only occurs in areas where there is local variation in environmental resources.

False

Genes that play a role in development may influence?

Cell division Cell migration Cell differentiation Cell death (apoptosis)

Patterns of speciation

Cladogenesis Allopatric speciation Natural selection Adaptive radiation

. Species occupy unique niches

Ecological species concept

Emphasizes habitat resources and the effect of a species on its environment/other species

Ecological species concept

Species are a direct result of speciation from an ancestral species

Evolutionary lineage concept

Reproductive isolating mechanisms

Mechanisms that prevent interbreeding between different species Consequence of genetic changes as species adapts to its environment

Behavioral Isolation

Sexual Attraction between males and females of different animal species Behaviors important in mate choice ex: Changes in song

Prezygotic barriers

Prevent formation of zygote habitat temporal behavioral mechanical Gametic

Reproductive isolation

Prevents one species from successfully interbreeding with other species

Macroevolution refers to evolutionary changes that?

Produce new species and groups of species

In order to survive 'walking' across dry ground, what other adaptation must a fish acquire? Binocular vision The ability to breathe air Protection from desiccation Legs

Protection from desiccation

According to Mayr's biological species concept, a species is defined by?

Reproductive isolation

Temporal Isolation

Species have different mating of flowering seasons or times of day or become sexually mature at different times of the year

Habitat Isolation

Species occupy different habitats so they never come in contact with each other

Hybrid breakdown

The F1 interspecies hybrid is viable and fertile, but succeeding generations become inviable

If interbreeding within the hybrid zone of the mountain pass decreased over time, what would you expect to happen to the Western and Eastern deer populations?

The Western and Eastern deer would become separate species because low gene flow among the deer in the hybrid zone would lead to allopatric speciation.

Consider the following hypothetical experiment: The PAX6 gene encodes a transcription factor that controls the development of the eye in both rodents and humans. A developing human embryo has its PAX6 gene removed and a mouse PAX6 gene inserted. Mouse and human PAX6 genes are homologous and have slightly different nucleotide sequences. However, the transcription factor (TF) encoded by mouse and human PAX6 genes have identical amino acid sequences. What is the most likely outcome and explanation for the outcome?

The embryo would develop normal human eyes. Although the gene encoding the TF comes from a mouse version of PAX6, the TF would act upon the human genome in a normal manner. The same genes that are responsible for eye morphogenesis in a normal human embryo would be turned off or on.

The ecological species concept classifies a species based on?

The niche the organism occupies in the environment

If each of the six organisms shown in the animation is a separate species, what does that imply? They have different diets. They are not capable of interbreeding. They do not live in the same location. They are different sizes.

They are not capable of interbreeding.

Cause of speciation

Underlying cause of speciation is the accumulation of genetic changes that ultimately promote enough differences so that we judge a population to constitute a unique species

Ecological factors

Variety of factors related to an organism's habitat can be used to distinguish one species from another

Species concepts

Way to define the concept of a species and/or provide an approach to distinguish one species from another

The evolution of one species into two or more species is called?

cladogenesis

The key difference between allopatric and sympatric is?

Whether speciation involves geographic seperation

Determine whether the examples are most likely to undergo allopatric or sympatric speciation. Allopatric

a fish species in different lakes a bird species that inhabits two different islands A sqiurrel population that gets split by a landslide

Ecotype

a genetically distinct population adapted to its local environment ex: bacterial

Indicate which organisms in the following examples would be considered separate species according to the biological species concept. Lions and tigers have been successfully interbred in captivity to produce viable offspring; hybrid males are infertile while females can be fertile. In the wild, lions live in Africa, tigers live in Asia, and the two species do not interbreed. Black bears in the United States can have coat colors ranging from blonde to jet black. Blonde-colored bears and black-colored bears occupy the same habitat and interbreed successfully. Many leopard frogs in the eastern United States look the same and can mate to produce a fertilized egg, but the embryo does not develop past the early stages. Some species of Galapagos finches can interbreed in captivity to produce viable, fertile offspring, but they show marked differences in their song patterns.

all of the above

Which of the following is not an example of a pre zygotic isolating mechanism? a. two species breed at different times of the year b. an egg from one species is fertilized by the sperm of another c. two different bird species have different mating calls d. two different species are geographically isolated from each other e. all of the above are pre zygotic mechanisms

b. an egg from one species is fertilized by the sperm of another

How do catfish "walk" across dry ground? by bouncing from pool to pool on their tails by always traveling downhill and sliding on their bellies on small, poorly developed feet by wiggling back and forth and pushing against their fins

by wiggling back and forth and pushing against their fins

Similar to the cichlids in Lake Tanganyika, the finches on the Galápagos Islands also evolved to allow many different species of finch to coexist by utilizing different food resources. How did the finches adapt to occupy different niches? changed beak size and shape changed feather coloration changed feather size and shape changed overall size and shape

changed beak size and shape