Ch 17

Auto and allopoidy

2 types of polyploidy

Zygote mortality Hybrid sterility F2 Fitness

3 Postzygotic isolating mechanisms

Habitat Isolation Temporal Isolation Behavioral Mechanical Gamete

5 Prezygotic isolating mechanisms

C

A biological species a. always looks different from other species. b. always has a different chromosome number than that of other species. c. is reproductively isolated from other species. d. never occupies the same niche as other species. e. does not survive long in the wild.

A

A change in expression of the Tbx5 gene can lead to which of the following problems? a. malformation of the legs b. incorrect development of the eye c. lack of development of neck vertebrae in a snake d. development of six legs in a grasshopper e. a shorter dorsal spine in stickleback fish

pax6

A gene called_______ is required for eye formation in all animals

Hybrid inviability

A hybrid zygote may die, because it is not viable

B

Allopatric, but not sympatric, speciation requires a. reproductive isolation. b. geographic isolation. c. spontaneous differences in males and females. d. prior hybridization. e. rapid rate of mutation.

postzygotic isolating mechanisms

Anatomical or physiological difference between two species that prevents successful reproduction after mating has taken place

Prezygotic isolating mechanisms

Anatomical, physiological, or behavioral difference between two species that prevents the possibility of mating

reinforcement

Connection between natural selection and reproductive isolation that occurs when two closely related species come back into contact after a period of isolation.

morphological species concept

Definition of a species that defines species by specific diagnostic traits

phylogenic species

Definition of a species that is determined by analysis of a phylogenetic tree to determine a common ancestor

zygote

Diploid cell formed by the union of two gametes

Sympatric

Does sympatric or allopatric speciation have a physical barrier prevents mating between populations?

Gamete isolation

Even if the gametes of two different species meet, they may not fuse to become a zygote

Mules

Example of post zygotic isolating mechanisms

monophyletic

Group of species including the most recent common ancestor and all its descendants

Polyploidy

Having a chromosome number that is a multiple greater than twice that of the monoploid number.

a doubling of the chromosomes

Hybridization is followed by...

Ecological release

In an ecosystem, the freedom of a species to expand its use of available resources due to an elimination of competition.

E

In the evolution of the modern horse, which of the following was the goal of the evolutionary process? a. large size b. single toe c. change in tooth size d. change in tooth shape e. None of these are correct.

hybridization

Interbreeding between two different species; typically prevented by prezygotic isolation mechanisms.

opportunistic

Is natural selection goal oriented or opportunistic

Macro evolution

Large-scale evolutionary change, such as the formation of new species.

C

Male moths recognize females of their species by sensing chemical signals called pheromones. This is an example of a.gamete isolation. b.habitat isolation. c.behavorial isolation. d.mechanical isolation. e.temporal isolation.

Behavioral Isolation

Many animal species have courtship patterns that allow males and females to recognize one another

biological species

Model by which new species arise when gene flow is disrupted between two populations, genetic changes accumulate, and the populations are subsequently unable to mate and produce viable offspring

Reproductive isolation

Model by which new species arise when gene flow is disrupted between two populations, genetic changes accumulate, and the populations are subsequently unable to mate and produce viable offspring.

Allopatric speciation

Model that proposes that new species arise due to an interruption of gene flow between populations that are separated geographically

Alloploidy

Occurs when two different but related species of plants hybridize

Speciation

Origin of new species due to the evolutionary process of descent with modification

Sympatric speciation

Origin of new species in populations that overlap geographically.

morphology

Physical characteristics that contribute to the appearance of an organism

diagnostic traits

Physical characteristics that contribute to the appearance of an organism.

Adaptive radiation

Rapid evolution of several species from a common ancestor into new ecological or geographical zones

Taxonomist

Scientist that investigates the identification and naming of new organisms.

Temporal Isolation

Several related species can live in the same locale, but if each reproduces at a different time of year, they do not attempt to mate

Convergent evolution

Similarity in structure in distantly related groups generally due to similiar selective pressures in like environments.

cryptic species

Species that are very similar in appearance but are considered separate species based on other characteristics, such as behavior or genetics

Speciation

Splitting one species into 2 or more species

T

T/F ... Hox genes have been found in all animals

F

T/F... Macro evolution occurs in a short span of time

F

T/F... The sequencing of genomes has shown that our DNA base sequence is very different to that of chimpanzees, mice, and indeed all vertebrates

T

T/F... Without variation evolution cannot occur

T

T/F... subtle changes in gene control can have profound effects on body shape

F

T/F... Humans are unable to use sterile plants

T

T/F.... Allopatric speciation can also cause a population to undergo adaptive radiation.

T

T/F.... microevolution and macroevolution are the result of the same processes, differing only in the scale at which they occur

biological species concept

The concept that defines species as groups of populations that have the potential to interbreed and that are reproductively isolated from other groups

B

The creation of new species due to geographic barriers is called a. isolation speciation. b. allopatric speciation. c. allelomorphic speciation. d. sympatric speciation. e. symbiotic speciation

Hybrid Sterility

The hybrid zygote may develop into a sterile adult.

B

The many species of Galápagos finches are each adapted to eating different foods. This is the result of a. gene flow. b. adaptive radiation. c. sympatric speciation. d. genetic drift. e. All of these are correct.

Pitx1

The presence of short spines in bottom-dwelling fish can be traced to a reduction in the development of the pelvic-fin bud in the embryo, and this reduction is due to the altered expression of a gene called...

Gradualistic model

This model proposes that speciation occurs after populations become isolated, with each group continuing slowly on its own evolutionary pathway

punctuated equilibrium model

This model says that the assembly of species in the fossil record can be explained by periods of equilibrium, or stasis, punctuated (interrupted) by periods of rapid, abrupt speciation, or change

analogous

Traits that evolve convergently in two unrelated lineages because of a response to a similar lifestyle or habitat are said to be

Mechanical Isolation

When animal genitalia or plant floral structures are incompatible, reproduction cannot occur

ecological release

When competition is reduced, it results in ...

Habitat isolation

When two species occupy different habitats, even within the same geographic range, they are less likely to meet and attempt to reproduce

B

Which gene is incorrectly matched to its function? a. Hox—body shape b. Pax6—body segmentation c. Tbx5—limb development d. Pitx1—pelvic-fin development e. All of these choices are correctly matched.

A

Which of the following are an example of analogous structures? a. wings of birds and bats b. hooves of horses and deer c. wings of moths and butterflies d. leaves on oak trees and maples e. arms of primates and cats

E

Which of the following events is part of macroevolution? a. speciation b. mutation c .gene flow d .natural selection e. All of these are correct.

E

Which of the following is not part of the gradualistic model of evolution? a. isolation of the population b. a slow change of the population c. the presence of fossils d. an ancestral population that gives rise to two separate populations e. a period of rapid change

E

Which of these is a prezygotic isolating mechanism? a.habitat isolation b.temporal isolation c.hybrid sterility d.zygote mortality e.Both a and b are correct.

E

Which of these is an example of mechanical isolation? a.Sperm cannot reach or fertilize an egg. b.Courtship patterns differ. c.Organisms live in different locales. d.Organisms reproduce at different times of the year. e.Genitalia are unsuitable to each other.

C

Which statement about speciation is not true? a. Speciation can occur rapidly or slowly. b. Developmental genes can account for rapid speciation. c. The fossil record gives no evidence that speciation can occur rapidly. d. Speciation always requires genetic changes, such as mutations, genetic drift, and natural selection.

speciation

a part of macroevolution that involves the formation of new species

Adaptive radiation

a type of speciation that occurs when a single ancestral species rapidly gives rise to a variety of new species as each adapts to a specific environment

Hox genes

control the number and appearance of repeated structures along the main body axes of vertebrates

sympatric

does polyploidy fall under allopatric or sympatric speciation

tbx5

encodes a protein that is a transcription factor that turns on the genes needed to make a limb during development

Postzygotic isolating mechanisms

mechanisms prevent hybrid offspring from developing and reproducing

convergent evolution

occur when a biological trait evolves in two unrelated species as a result of exposure to similar environments

Adaption

occurs only because the members of a population with an advantage are able to have more offspring than other members

Autoploidy

occurs when a diploid plant produces diploid gametes due to nondisjunction during meiosis

Evolutionary species concept

recognizes that every species has its own evolutionary history, at least part of which is in the fossil records

Allopatric speciation

the eventual result of populations that have become separated by a geographic or other type of physical barrier

Macro evolution

the result of the accumulation of microevolutionary change that results in the formation of new species