The diagram illustrates which mode of speciation?

Answer: Allopatric speciation Allopatric speciation is driven by a geographic barrier (the river) physically isolating two populations so gene flow ceases and divergence proceeds independently.

Speciation rates are highest when

Answer: Populations are isolated and face new ecological opportunities (e.g., new island, post-extinction niches) Isolation + new niches → rapid divergence. Adaptive radiations after mass extinctions illustrate this.

Polyploidy producing immediate reproductive isolation from the parent species exemplifies which mode of speciation?

Answer: Sympatric speciation (in plants) Polyploidy can instantly create reproductive isolation within the same geographic area: tetraploids x diploids yield sterile triploids. It is a major mechanism of sympatric speciation, especially in plants.

AP Biology · Topic 7.10

Speciation Practice

Part of Natural Selection.(EVO-1.J)

Practice questions

Want a predicted score for the whole AP BIO exam? Take the 20-question diagnostic and Lumi will plan the rest.

Take diagnosticarrow_forward Practice all 7.10

Sample questions

5 of 16 — sign in to practice the rest with adaptive difficulty and mastery tracking.

Sample 1difficulty 1/5
$A river forms across the range of a rodent species, splitting it into two populations.$
$The diagram illustrates which mode of speciation?$
- A
  $Allopatric speciation$
  check_circle
- B
  $Parapatric speciation$
- C
  $Peripatric reinforcement$
- D
  $Sympatric speciation$
Why
$Allopatric speciation is driven by a geographic barrier (the river) physically isolating two populations so gene flow ceases and divergence proceeds independently.$
View full solution & statsarrow_forward
Sample 2difficulty 2/5
$Speciation rates are highest when$
- A
  $Population sizes are very large and gene flow homogenizes alleles across the entire range$
- B
  $Environments are extremely stable and existing species fully saturate every available niche$
- C
  $Mutation rates drop to zero and selection cannot act on any new heritable variation arising$
- D
  $Populations are isolated and face new ecological opportunities (e.g., new island, post-extinction niches)$
  check_circle
Why
$Isolation + new niches \to rapid divergence. Adaptive radiations after mass extinctions illustrate this.$
View full solution & statsarrow_forward
Sample 3difficulty 2/5
$Polyploidy producing immediate reproductive isolation from the parent species exemplifies which mode of speciation?$
- A
  $Sympatric speciation (in plants)$
  check_circle
- B
  $Adaptive radiation$
- C
  $Allopatric speciation$
- D
  $Peripatric speciation$
Why
$Polyploidy can instantly create reproductive isolation within the same geographic area: tetraploids x diploids yield sterile triploids. It is a major mechanism of sympatric speciation, especially in plants.$
View full solution & statsarrow_forward
Sample 4difficulty 2/5
$A single fish population in one lake diverges into two reproductively isolated forms based on feeding depth. This is$
- A
  $Sympatric speciation$
  check_circle
- B
  $Parapatric speciation with barrier$
- C
  $Peripatric speciation$
- D
  $Allopatric speciation$
Why
$Sympatric speciation occurs without geographic isolation; ecological niche differentiation (here feeding depth) creates assortative mating and reproductive isolation within a single area.$
View full solution & statsarrow_forward
Sample 5difficulty 2/5
$Under the biological species concept, two populations are different species when they$
- A
  $Cannot interbreed and produce fertile offspring in nature$
  check_circle
- B
  $Live in different geographic regions or habitats$
- C
  $Have different morphology and coloration from each other$
- D
  $Have different numbers of chromosomes from each other$
Why
$Reproductive isolation defines species under Mayr's biological species concept.$
View full solution & statsarrow_forward

Predict my AP scorearrow_forward