Origins of Specie & Macroevolution-Week 15 Flashcards
Scientists found that different beak shapes correlate with different mating songs in Darwin’s finches. Which hypothesis is most likely to explain this?
Adaptation to different food sources likely occurred after reproductive isolation in Darwin’s finches.
Adaptation to different food sources led to behavioral isolation in Darwin’s finches.
Mating songs are primarily determined by the acoustics of different beaks.
Darwin’s finches are not different species according to the Biological Species Concept.
Adaptation to different food sources led to behavioral isolation in Darwin’s finches.
Many male songbirds have very distinctive songs that are used to attract females. These songs are an example of a _________isolating mechanism.
postzygotic, ecological
postzygotic, mechanical
prezygotic, behavioral
prezygotic, temporal
prezygotic, behavioral
Males of many marsupial species have forked penises that are incompatible with the anatomy of female placental mammals. What type of isolating mechanism does this represent?
temporal isolation
mechanical incompatibility
ecological isolation
hybrid sterility
mechanical incompatibility
Which isolating mechanism is postzygotic?
mechanical isolation
behavioral isolation
ecological isolation
hybrid sterility
hybrid sterility
In the southeastern U.S., two species of wild lettuce (Lactuca) do not usually form hybrids, because they bloom at different seasons. The means of isolation appears to be
prezygotic and geographical.
prezygotic and mechanical.
prezygotic and temporal.
postzygotic and behavioral.
prezygotic and temporal.
If a new species is produced by the interbreeding of two members of distinct species, this would be _________ speciation achieved via _________.
sympatric; allopolyploidy
sympatric; autopolyploidy
allopatric; autopolyploidy
allopatric; allopolyploidy
sympatric; allopolyploidy
Evolution acts at the level of the
population.
individual.
community.
ecosystem.
population
Which statement is true about speciation on island archipelagos?
Speciation by polyploidy is most common.
Ecological competition may cause new species to go extinct slowing speciation.
Most speciation occurs allopatrically.
Species clusters are less common.
Most speciation occurs allopatrically.
NASA Scientists send a small population of dogs to an earth-like exoplanet in order to test if it will be hospitable for human colonization. Through a random lottery, only Great Dane and St. Bernard dog breeds are sent, and the resulting population consists of tall, longhaired dogs. After 100 years these dogs return to Earth and are no longer able to mate with Earth dogs. This scenario is an example of
sympatric speciation through genetic drift.
allopatric speciation through natural selection.
allopatric speciation through genetic drift.
sympatric speciation through natural selection.
allopatric speciation through genetic drift.
In 1938, scientists found a population of coelacanths in the Indian Ocean. This fish species is considered a “living fossil” and appears not to have changed morphologically for 80 million years. This discovery supports the _________ model of evolution.
natural selection
gradualism
punctuated equilibrium
adaptation
punctuated equilibrium
Due to character displacement, two closely related species may differ most morphologically when they
occupy the same niche.
are sympatric.
share a common ancestor.
are allopatric.
are sympatric.
Two populations that inhabit the same area but remain genetically distinct can best be called
sympatric species.
genera.
allopatric species.
subspecies (races).
sympatric species.
Which isolating mechanism is postzygotic?
hybrid sterility
behavioral isolation
ecological isolation
mechanical isolation
hybrid sterility
A type of isolating mechanism that leads to reproductive isolation after a hybrid zygote has formed is called a _________ isolating mechanism.
hybridization
postzygotic
adaptive
prezygotic
postzygotic
How many mass extinctions have been identified during the history of life on Earth?
Two
Three
Five
Four
Five
The model that assumes that evolution proceeds with slow successive change in a given evolutionary line is referred to as
punctuated equilibrium.
the sympatric model.
gradualism.
the allopatric model.
gradualism
The sunflower species Helianthus anomalus is thought to have been formed by hybridization between the sunflower species H. petiolaris and H. annuus because it contains a set of chromsomes from both parental species. H. anomalus is most likely an example of instantaneous speciation through
allopolyploidy.
autopolyploidy.
parthenogenesis.
hybrid sterility.
allopolyploidy.
The hundreds of species of Drosophila in Hawaii exhibit different mating rituals. This isolating mechanism is
postzygotic and mechanical.
prezygotic and temporal.
prezygotic and ecological.
prezygotic and behavioral.
prezygotic and behavioral.
When species are kept separate by preventing the formation of hybrid zygotes, the mechanism that keeps the species separate is known as a _________ isolating mechanism.
prezygotic
adaptive
hybridization
postzygotic
prezygotic
If two species are competing for the same resource, then either one species is likely to go extinct through competitive exclusion, or natural selection will drive the evolution of
hybrids.
polyploid individuals.
character displacement.
prezygotic isolating mechanisms.
character displacement
If two species are competing for the same resource, then either one species is likely to go extinct through competitive exclusion, or natural selection will drive the evolution of
hybrids.
polyploid individuals.
character displacement.
prezygotic isolating mechanisms.
character displacement
The type of speciation that results in the formation of separate species as a result of geographic isolation is called _________speciation.
gradual
sympatric
adaptive
allopatric
allopatric
A type of isolating mechanism that leads to reproductive isolation after a hybrid zygote has formed is called a _________ isolating mechanism.
hybridization
prezygotic
adaptive
postzygotic
postzygotic
Punctuated equilibrium proposed by Eldredge and Gould in 197 is an evolutionary process that involves
gradual change observable in the fossil record followed by periods of stasis.
“spurts” of change observable in the fossil record with very little if any stasis.
gradual change observable in the fossil record with very little, if any, stasis.
“spurts” of change observable in the fossil record followed by periods of stasis.
“spurts” of change observable in the fossil record followed by periods of stasis.