What hypothesis did the researchers test in this study?
Reproductive isolation increases with geographic distance between dusky salamander populations
.
What is the geographic distance between salamander populations?
a. Geographically separated populations of dusky salamanders
gradually diverge
, and the divergence increases with geographic distance.
What hypothesis did the researchers test in this study salamanders?
What hypothesis did the researchers test in this study?
Reproductive isolation increases with geographic distance between dusky salamander populations
.
How is the value of the reproductive isolation index calculated?
The reproductive isolation value for two populations is
the sum of the proportion of successful matings of each type within populations (AA + BB) minus the sum of the proportion of successful matings of each type between populations (AB + BA)
.
What do Dodd's experiments with fruit flies indicate?
What do Dodd's experiments with fruit flies indicate?
Reproductive barriers will arise most quickly if isolated populations experience and become adapted to differing environments
. … A change in a single gene may produce effective reproductive barriers between populations in some cases.
Which of these is an example of temporal isolation between two species?
For example, a peculiar form of temporal isolation has been observed between two closely related species of
cicadas of the genus Magicicada
in the United States. Sexually mature adults of Magicicada tredecim emerge every 13 years, whereas those of M. septendecim emerge every 17 years.
What is genetic drift Chapter 24?
a set of organisms with a unique genetic history. What is genetic drift?
A change in allele frequencies caused by random events
. Why are the large finches now living on the Galápagos Islands different from the original source population from a nearby island? All three answers are correct.
Is rapid speciation under conditions in which there is little competition?
(Why:
Adaptive radiation
is rapid speciation under conditions in which there is little competition. … (Why: The finches that initially immigrated to the Galapagos Islands experienced little competition, the result of which was the promotion of speciation.
What type of speciation is caused by a barrier such as the Grand Canyon?
The canyon became a geographic barrier separating the forests and squirrels on each rim. One population of squirrels had become two separate populations that could no longer reproduce. According to National Geographic, this type of speciation is
allopatric speciation
.
Why is the hybrid plant sterile quizlet?
Why is the hybrid plant sterile?
Meiosis cannot occur. and The cells do not contain homologous chromosomes
. The sequence of events illustrated in this figure results in a fertile hybrid plant called an allopolyploid.
What is the most important factor that holds a gene pool?
Terms in this set (10) What is the most important factor that holds a gene pool of a species together and prevents speciation? –
Gene flow refers to the transfer of alleles among populations
.
Do you still think lions and tigers are separate species?
Lions and tigers live on different continents and differ in many ways. In nature, they do not hybridize, or interbreed. Therefore, according to the biological species concept,
lions and tigers are separate species
.
Which of the following is the first step in allopatric speciation quizlet?
Which of the following is the first step in allopatric speciation? Allopatric speciation occurs when
a population of organisms is geographically separated long enough for significant changes to occur
. After a period of time, the populations may no longer be able to interbreed.
What is a good example of Intrasexual selection?
Intrasexual selection, on the other hand, occurs between members of the same sex. For example,
male sea lions compete for dominance over rookeries of females
. Here, intrasexual selection acts on the physiology of the sea lion, to make it large enough to compete with other males for a group of females.
How do you know if speciation has occurred?
For speciation to occur,
two new populations must be formed from one original population
, and they must evolve in such a way that it becomes impossible for individuals from the two new populations to interbreed.
How do you explain natural selection?
Natural selection is the
process through which populations of living organisms adapt and change
. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others.
