Biology 182: Chapter 20

A storm blows a small group of migrating birds off course and they land on an island, where they remain for 100 generations. At this time, a second storm brings more birds from the mainland population to the island. These new birds cannot mate with the established birds, even though they are originally from the same population. What mechanisms are likely to have been involved in bringing about this speciation? Select all that apply. 1. Genetic drift 2. Polyploidy in the mainland bird population. 3. Founder effect 4. Adaptation to a new ecological niche

1. Genetic drift 3. Founder effect 4. Adaptation to a new ecological niche

What criteria can be used to identify species? Select all that apply. 1. The ability to interbreed 2. Molecular similarity 3. Ecological factors 4. Evolutionary relationships

1. The ability to interbreed 2. Molecular similarity 3. Ecological factors 4. Evolutionary relationships

Development of an animal is connected to the genes that are expressed during development. What roles have been proposed for Hox genes in the evolution and morphology of animal species? Select all that apply. 1. Variation in the number of Hox genes has led to the evolution of new animal species. 2. An increase in the number of Hox genes leads to an increase in the body size of an animal. 3. The greater the number of Hox genes the more complex the body plan of the animal. 4. The clustering of Hox genes has only evolved in vertebrates and is responsible for the evolution of vertebrae.

1. Variation in the number of Hox genes has led to the evolution of new animal species. ase in the body size of an animal. 3. The greater the number of Hox genes the more complex the body plan of the animal.

A tick population in a rural, wooded area uses deer as its primary host species. Eventually, humans begin to move into the area, bringing their pets along with them. Certain individuals within the tick population start to use dogs as their primary hosts, and eventually start to prefer dogs over deer. Other individuals continue to use deer for their primary host. Could this difference in host preference lead to speciation? Why or why not? Select all correct answers. 1. Yes, because temporal isolation could occur due to differences in host quality. 2. No, because the ticks inhabit the same region and therefore experience the same mechanisms of evolution. 3. Yes, because the ticks' host preference may be inherited, leading to an accumulation of genetic differences between ticks that use deer and ticks that use dogs. 4. No, because one of the hosts will lead to higher fitness and the ticks that prefer the other host will be eradicated.

1. Yes, because temporal isolation could occur due to differences in host quality. 3. Yes, because the ticks' host preference may be inherited, leading to an accumulation of genetic differences between ticks that use deer and ticks that use dogs.

Why is De Queiroz's general lineage species concept is receiving significant support? Select all that apply. 1. it includes criteria from all other species concepts 2. many scientists would like to have a single, agreed upon species concept 3. it is not meant to be used for extinct species 4. it can incorporate molecular, ecological, and morphological factors into a single species concept 5. it presents clear rules on the number of differences needed to qualify two populations as two distinct species

1. it includes criteria from all other species concepts 2. many scientists would like to have a single, agreed upon species concept 4. it can incorporate molecular, ecological, and morphological factors into a single species concept

Which of the following situations would be MOST likely to produce a new species? A. A group of polyploid individuals arises by an abnormal mitosis. The polyploids can only produce viable offspring by mating with each other. B. Several individuals join an existing population and introduce several new, beneficial alleles. C. Several individuals colonize a new area and establish a population. Migration between the two populations is common. D. An existing species becomes subdivided by a glacier and the resulting groups remain physically isolated from each other for thousands of years. When the glacier melts, the two groups are able to interbreed. E. A volcano erupts and kills all of the frogs on an island, along with many other species. New frogs colonize the island and begin reproducing rapidly because there are no longer any frog predators.

A. A group of polyploid individuals arises by an abnormal mitosis. The polyploids can only produce viable offspring by mating with each other.

Which gene is correctly matched with its evolutionary significance? A. The Hox genes - evolution of body plans. B. The BMP4 gene - evolution of lungs. C. The gremlin gene - evolution of the simple eye. D. The Pax6 - evolution of skull shape.

A. The Hox genes - evolution of body plans.

Approximately 3.5 million years ago the Isthmus of Panama formed. This new landmass severed the connection between the Pacific Ocean and the Caribbean Sea. An ancestral fish population (porkfish) was split in two by this event; the two populations no longer interbreed and are two distinct species. This type of speciation is called A. allopatric speciation. B. parapatric speciation. C. hybridization. D. sympatric speciation. E. sexual selection due to ecological variation.

A. allopatric speciation.

The function of BMP4 is to ____________ while the function of gremlin is to __________ BMP4. A. cause apoptosis; inhibit the function of B. induce mitosis; amplify expression of C. inhibit growth; amplify expression of D. induce mitosis; inhibit the function of E. cause apoptosis; act as a catalyst for

A. cause apoptosis; inhibit the function of

During spring time in Maine, male moose often enter a cow pasture and begin calling to the female cows. The moose may even try to mount the female but the male genitalia do not fit properly inside the female genitalia. This is an example of A. mechanical isolation. B. temporal isolation. C. habitat isolation. D. behavioral isolation. E. gametic isolation.

A. mechanical isolation.

The phenotypic changes shown in the figure above represent A. punctuated equlibrium. B. horizontal gene transfer. C. gradualism. D. speciation based on sexual selection.

A. punctuated equlibrium.

If two populations are geographically restricted groups of the same species, but display one or more traits that are somewhat different, the two groups are sometimes classified as A. subspecies B. phenotypes C. macrospecies D. genetic clones

A. subspecies

Dandelions, Taraxacum officinale, are plants that asexually produce fruitlike propagules. Sexual reproduction is very rare in this organism. Which species concept would be least useful in defining dandelions as a species? A. Phylogenetic species concept. B. Biological species concept. C. Evolutionary species concept. D. Ecological species concept. E. Both the evolutionary and ecological species concepts.

B. Biological species concept.

Based on the figure below, how many groups (clusters) of Hox genes does each type of animal have?  A. Mammals: 4 groups; Flatworms: 4 groups; Sponge: 2 groups; Anemones: 1 group. B. Mammals: 4 groups; Flatworms: 4 groups; Sponge: 1 groups; Anemones: 2 group. C. Mammals: 11 groups; Flatworms: 4 groups; Sponge: 1 groups; Anemones: 4 groups. D. Mammals: 27 groups; Flatworms: 4 groups; Sponge: 2 groups; Anemones: 1 group. E. All animals must have at least 2 groups because all animals have a posterior and anterior end.

B. Mammals: 4 groups; Flatworms: 4 groups; Sponge: 1 groups; Anemones: 2 group.

A population of mountain goats are split because of the formation of a glacier. After 500 years the glacier melts and the two goat populations are free to move between the two areas. Under what conditions might a hybrid zone will occur? A. Both pre- and post-zygotic isolating mechanisms have arisen. B. Reproductive isolation is incomplete. C. Pre-zygotic isolating mechanisms have arisen. D. Post-zygotic isolating mechanisms have arisen. E. Gene flow between the two populations does not occur.

B. Reproductive isolation is incomplete.

A scientist is studying a population of crickets and finds that there is variation in the songs used by males to call for mates. Some males call with high pitched, 3 chirp songs and some call with low pitched, 4 chirp songs. However, offspring from the two types of males are able to interbreed, so the scientist classifies the population as a single cricket species and goes on to another project. One year later, a mutation arises in a female cricket that makes her unable to hear high frequencies. Ten years later, a graduate student returns to the same cricket population and discovers that there are now two distinct cricket species in the area, although they appear morphologically identical. What is the most likely explanation? A. Temporal isolation has led to allopatric speciation. B. Sexual selection has led to sympatric speciation. C. Habitat isolation has led to allopatric speciation. D. Mechanical isolation has led to sympatric speciation. E. Gametic isolation has led to sympatric speciation.

B. Sexual selection has led to sympatric speciation.

Based on the figure below, what statement could you make about the development of human versus chimpanzee skulls.  A. The human and chimp skulls develop similarly until adulthood, when human jaw development slows down relative to the chimpanzee. B. The human and chimp skulls develop similarly until the infant stage, when human jaw development slows down relative to the chimpanzee. C. Human skull development shows paedomorphosis because the jaw retains its small size while the chimp jaw continues to grow even in adulthood. D. The human and chimp skulls develop similarly until the infant stage, when human cranium development slows down relative to the chimpanzee. E. The human and chimp skulls develop similarly during the fetal stage, after which point chimpanzee cranium growth outpaces humans.

B. The human and chimp skulls develop similarly until the infant stage, when human jaw development slows down relative to the chimpanzee.

The Northern leopard frog (Rana pipiens) and Southern leopard frog (Rana utricularia) are morphologically similar, but their mating calls sound very different. Based on this, what is the best explanation for why these frogs are considered separate species? A. They are too morphologically different to interbreed. B. They have undergone behavioral isolation which prevents them from interbreeding. C. They have undergone habitat isolation because one species is entirely terrestrial while the other is entirely aquatic. D. They do interbreed, but produce sterile hybrids.

B. They have undergone behavioral isolation which prevents them from interbreeding.

Allopatric speciation occurs because a population A. merges with another population of the same species. B. becomes geographically isolated and undergoes genetic change. C. becomes extinct and is replaced by a population of a different species. D. shows little genetic change from generation to generation. E. hybrid sterility occurs.

B. becomes geographically isolated and undergoes genetic change.

A group of individuals that can interbreed in nature and produce viable offspring would be considered to be a species according to the A. phylogenetic species concept. B. biological species concept. C. evolutionary species concept. D. ecological species concept. E. general lineage concept.

B. biological species concept.

The Pax6 gene A. is a master control gene for limb development. B. codes for a protein that controls the expression genes related to eye development. C. has no known homologs. D. is a homolog to the eyeless gene in rodents.

B. codes for a protein that controls the expression genes related to eye development.

What mechanism makes it difficult to classify bacteria into distinct species groups? A. vertical evolution. B. horizontal gene transfer. C. sexual reproduction. D. asexual reproduction. E. low mutation rates.

B. horizontal gene transfer.

If goats are crossed with sheep, embryos will form but cease development and spontaneously abort. This is an example of A. a prezygotic mechanism. B. hybrid inviability. C. hybrid sterility. D. hybrid breakdown. E. spermatic behavior.

B. hybrid inviability.

Two species of salamander have similar ranges, but one breeds from January to March, while the second one breeds from March to May. This is an example of A. mechanical isolation. B. temporal isolation. C. habitat isolation. D. behavioral isolation. E. gametic isolation.

B. temporal isolation.

Studies of the Pax6 gene and its homologs suggest that A. the eye has evolved independently multiple times. B. the eyes of many different species are descended from a common ancestor. C. the master genes of the eye in various species are not homologous. D. the simple eyes of invertebrates and complex eyes of vertebrates arose from two different ancestral control genes.

B. the eyes of many different species are descended from a common ancestor.

How would you best explain the correlation between an increase in Hox genes and an increase in animal body complexity? A. Different Hox genes are expressed in different regions of the body. B. Hox genes have duplicated several times during animal evolution, but they are not responsible for an increase in body plan complexity. C. An increase in the number of Hox genes allows for greater specialization in different body regions. D. An increase in the number of Hox genes meant that fewer regulatory genes could be controlled in a species. E. As the number of Hox genes increases, the number of genes encoding proteins for appendage development decreases.

C. An increase in the number of Hox genes allows for greater specialization in different body regions.

Podos measured finch beak depth and correlated this with characteristics of their songs. Using the figure below, what species of bird with a vocal constraint between 2 and 3 has the largest beak depth? A. G. magnirostris B. C. psittacula C. G. fortis D. G. scandens E. C. pallidus

C. G. fortis

To prepare for a hiking trip in the Appalachian mountains, you buy several field guides for the region from a used bookstore. You notice that the older guides list a single species of tiger swallowtail butterfly, Papilio glaucus, and an Appalachian morph of this species. However, the newest guide list two separate species, P. glaucus and P. appalachiensis. The authors of this guide state that the biological species concept was used in determining their classifications. What do you think led them to list two separate species of tiger swallowtail? A. The discovery that P. glaucus and P. appalachiensis interbreed in the wild. B. The discovery that P. glaucus and P. appalachiensis have a genomic similarity of 99%. C. The discovery that P. glaucus and P. appalachiensis do not interbreed in the wild. D. The discovery that P. glaucus and P. appalachiensis have distinct differences in wing coloration. E. The discovery that P. glaucus and P. appalachiensis feed on different host plants.

C. The discovery that P. glaucus and P. appalachiensis do not interbreed in the wild.

You discover a new species of lily that has 10 chromosomes (2n=10). Genetic testing reveals that it arose from the interbreeding of two other species of lilies, one of which has 12 chromosomes, and one of which has 8 chromosomes. What is the correct term for the new lily species? A. autopolyploid B. allopolyploid C. allodiploid D. allotetrapoloid

C. allodiploid

The figure below illustrates that  A. genetic changes in an ancestral Pax6 gene contributed to the evolution of the mammal eye, while the Drosphila eye arose independently. B. most animal species have eyes with one photoreceptor and one pigment cell. C. eye complexity has not significantly increased since the late Triassic when most modern insect families arose. D. the retina and cornea developed first, but then were secondarily lost in insects such as Drosphilia. E. although the mammal eye possesses more cell types and greater complexity than the Drosphilia eye, both arose from genetic changes to an ancestral Pax6 gene.

C. eye complexity has not significantly increased since the late Triassic when most modern insect families arose.

American sycamore (Platanus occidentalis) and European sycamore (Platanus orientalis) are tree species that will interbreed if planted nearby but will not normally interbreed because they occur on different continents. This is an example of A. mechanical isolation. B. temporal isolation. C. habitat isolation. D. behavioral isolation. E. gametic isolation.

C. habitat isolation.

A liger is a result from a male lion and a female tiger. Male ligers cannot produce offspring. This is an example of A. a prezygotic mechanism. B. hybrid inviability. C. hybrid sterility. D. hybrid breakdown. E. a prezygotic mechanism and hybrid sterility are correct.

C. hybrid sterility.

The process of evolutionary changes that result in formation of new species and groups of species is called A. temporal evolution. B. artificial selection. C. macroevolution. D. serial evolution. E. a combination of temporal and serial evolution.

C. macroevolution.

Paedomorphosis is A. the formation of limbs from fins in the evolution of land vertebrates. B. the change from radial to bilateral symmetry in the evolution of plants and animals. C. the retention of juvenile traits in an adult organism. D. an earlier development of adult traits in an organism. E. the development of different types of eyes from a simpler form.

C. the retention of juvenile traits in an adult organism.

A disadvantage of using DNA or RNA sequences to identify species is that A. it can only be used for sexually reproducing organisms. B. it cannot be used for extinct species. C. there are no rules for determining the number of sequence differences needed for a new species. D. if can be misleading because many species exhibit large variation in phenotype.

C. there are no rules for determining the number of sequence differences needed for a new species.

Speciation can arise through abrupt events, such as changes in chromosome number, or as a consequence of adaptation to different ecological niches. What is the term for the splitting or diverging of a population into two or more species? Which of the figures above represents this term? A. Anagenesis; Figure A. B. Anagenesis; Figure B. C. Cladogenesis; Figure A. D. Cladogenesis; Figure B. E. Cladogenesis; Both Figure A and B can represent this term.

D. Cladogenesis; Figure B.

What field of biology compares the development of organisms in order to better understand mechanisms of evolutionary change? A. Pattern formation. B. Punctuated equlibrium. C. Cell biology. D. Evolutionary developmental biology. E. Endocrine biology.

D. Evolutionary developmental biology.

Your senior thesis project involves working out the taxonomy of Florida skinks. To accomplish this, you examine skink specimens for morphological differences, compare nucleotide and amino acid sequences, and observe the skinks' reproductive behavior and habitat types. Once you have completed the taxonomy and written the thesis, you give it to your professor for comments. She tells you that you did a great job and should try to get your work published! However, she suggests you indicate in the introduction what species concept you used to make your classifications. What statement would you add? A. Taxonomic determinations were made based on the ecological species concept. B. Taxonomic determinations were made based on the biological species concept. C. Taxonomic determinations were made based on the evolutionary lineage species concept. D. Taxonomic determinations were made based on the general lineage species concept.

D. Taxonomic determinations were made based on the general lineage species concept.

Adaptive radiation is likely to have led to which of the following? A. The divergence of a single pea aphid population into two distinct species. B. The evolution of the horse via changes in climate and food supply. C. The long period of equilibrium in a bat species in the Mariana Islands. D. The 1,000 species of Drosophila found dispersed throughout the Hawaiian Islands.

D. The 1,000 species of Drosophila found dispersed throughout the Hawaiian Islands

Frogs "croak" at night to lure females for mating. Females are attracted only to the song of their species. This is an example of A. mechanical isolation. B. temporal isolation. C. habitat isolation. D. behavioral isolation. E. gametic isolation.

D. behavioral isolation.

Under the ___________ , species are identified based on their unique habitat requirements. A. phylogenetic species concept B. biological species concept C. evolutionary species concept D. ecological species concept E. general lineage concept

D. ecological species concept

Reproductive isolation in Darwin's finches was studied by Podos. He measured beak size and found a correlation between this and the finches' A. song. B. ability to attract certain mates. C. flight patterns. D. song and ability to attract certain mates. E. flight patterns and song.

D. song and ability to attract certain mates.

In comparing the development of the unwebbed foot of the chicken and webbed foot of a duck, what differences are there in the expression of BMP4 and gremiln? A. Chicken feet only express BMP4 while duck feet only express gremiln. B. BMP4 is expressed similarly in both chicken and duck feet, while gremlin is only expressed in duck feet. C. Gremlin is expressed similarly in both chicken and duck feet, while BMP4 is only expressed in between chicken toes. D. Both BMP4 and gremlin are expressed similarly in chicken and duck feet. E. BMP4 is expressed similarly in both chicken and duck feet, while gremlin is not expressed between the toes of chicken feet.

E. BMP4 is expressed similarly in both chicken and duck feet, while gremlin is not expressed between the toes of chicken feet.

A confused frog deposits its sperm onto a toad's eggs as they are being laid. No offspring develop because the frog's sperm are unable to penetrate the toad's egg. This is an example of A. mechanical isolation. B. temporal isolation. C. habitat isolation. D. behavioral isolation. E. gametic isolation.

E. gametic isolation.

The phenomenon in which one region of the body grows faster than another among different species is called A. paedomorphosis. B. Gremlin and BMP4 interaction. C. Hox gene clustering. D. phenotypic variation. E. heterochrony.

E. heterochrony.

Sympatric speciation differs from allopatric speciation because in sympatric speciation A. a population becomes geographically isolated. B. two populations of the same species merge to form a single population. C. polyploidy must first arise. D. hybrid zones form. E. there are no physcial barriers against interbreeding.

E. there are no physcial barriers against interbreeding.

T/F The pace of evolution remains constant despite sudden environmental shifts such as climate change.

FALSE

T/F Two species of three-spined stickleback fish live in a single lake in British Columbia. They are closely related but occupy different niches. They exist nowhere else. These species most likely arose by sympatric speciation from a single species of three-spined stickleback.

TRUE

T/F The Mexican axolotl (Ambystoma mexicanum) is an amphibian that has a derived mode of development characterized by metamorphic failure. This mode of development results in an entirely aquatic life cycle and is an example of paedomorphosis.

TRUE

According to the concept of ___________, species evolve continuously over long spans of time.

gradualism