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Overview of Speciation

Speciation is where two new species arise from a single species. This happens when two populations are prevented from interbreeding.

Reproductive isolation

Reproductive isolation

  • A species is defined as a group of organisms that can successfully interbreed to produce fertile offspring.
  • If two populations are prevented from interbreeding, differences begin to accumulate in the two gene pools.
  • Gene flow is the movement of alleles between a population. When two populations are reproductively isolated, the gene flow of the populations is restricted.
  • The two populations are said to be reproductively isolated.
Accumulation of differences

Accumulation of differences

  • If the gene pools are reproductively isolated for an extended period of time, they will eventually accumulate enough genetic differences that the two populations can no longer interbreed.
  • If individuals from the two populations can no longer interbreed to produce fertile offspring, the two populations are considered separate species.
Speciation

Speciation

  • Speciation is when two (or more) populations have been reproductively isolated to produce two (or more) separate species.
  • This is how the thousands of species that exist today have been produced.
Jump to other topics
1

Unity & Diversity - Molecules

2

Unity & Diversity - Cells

3

Unity & Diversity - Organisms

4

Unity & Diversity - Ecosystems

5

Form & Function - Molecules

6

Form & Function - Cells

7

Form & Function - Organisms

8

Form & Function - Ecosystems

9

Interaction & Interdependence - Molecules

10

Interaction & Interdependence - Cells

11

Interaction & Interdependence - Organisms

12

Interaction & Interdependence - Ecosystems

12.1

Populations & Communities

12.2

Transfers of Energy & Matter

13

Continuity & Change - Molecules

14

Continuity & Change - Cells

15

Continuity & Change - Organisms

16

Continuity & Change - Ecosystems

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