Chapter 21 Learning Curve

Which of the statements is true regarding adaptive radiation?

adaptive radiation is more likely to occur in a population produced by a dispersal event than in a long established population on a continent

A zookeeper is very upset because one of the lions jumped the fence of his enclosure and mated with a neighboring tigress. This mating produced a "liger." Which of the statements is likely true of this liger cub?

due to genetic incompatibility between the lion and tiger, the liger cub will likely be sterile

If two populations are reproductively isolated from one another, they must be genetically isolated from each other and, therefore, cannot belong to the same species.

false

In general, allopatric species will evolve pre-zygotic isolating mechanisms more rapidly than sympatric species.

false

You would expect similar species with a different number of chromosomes to be genetically compatible and, therefore, able to reproduce fertile offspring.

false

if natural selection is the driving force for speciation of two competing subspecies, you would expect to see a bell shaped distribution of selected phenotypes after selection

false

post zygotic reproductive isolation may be due to temporal or ecological separation

false

over a long period of time, you would expect a neutral mutation to ____ within a large population

increase or decrease in frequency

when you use a field guid to identify a species by its appearance, you are applying the ____ concept

morphospecies

You are an experienced naturalist and biologist and you observe two birds mating that you do not believe are members of the same species. The eggs from this breeding do not hatch, and when you obtain one of the eggs, you find embryonic development stopped not long after fertilization. Which of the following conclusions is supported by these observations?

post zygotic factors prevented successful production of offspring

If two individuals from different species attempt to mate, but fertilization fails to occur, this is likely the result of _____. However, if such a mating produces a zygote that fails to form a viable embryo, this is likely the result of _____.

pre zygotic factors post zygotic factors

a researcher is trying to determine whether different populations of asexually reproducing bacteria belong to the same species. what concept will be most helpful in making this determination?

the ecological species concept

Imagine that a zoo in Sri Lanka has started an elephant-breeding program. Zookeepers have introduced an Indian and Sri Lankan elephant into the same enclosure. What will be the result of this mating?

this mating will demonstrate that these elephants are members of the same species and will produce fertile offspring

when two populations have undergone divergence in allopatry long enough to be unable to produce fertile offspring, they are different enough to be considered two different species

true

While in South America, you come across what you think are two groups of birds in the same location. They are nearly identical aside from their color. After years of observation, you conclude that the birds eat similar diets and share similar behaviors but do not reproduce with each other. These groups of birds appear to be an example of:

two different species on the basis of reproductive behavior

which of the scenarios represents genetic incompatibility?

two groups of snakes do not produce fertile offspring because they have a different number of chromosomes