Mechanism Of Speciation

Speciation is the evolutionary process by which reproductively isolated biological populations evolve to become distinct species.There are few mechanisms through which this process can be well understood.

1. Mechanism of speciation B y- Anshika Bansal 135019 1

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3. Modes of speciation ALLOPATRIC SPECIATION REPRODUCTION ISOLATION PERIPATRIC SPECIATION SYMPATRIC SPECIATION (*) POLYPLOIDY PARAPATRIC SPECIATION 3

4. Allopatric ( allo =other, patric =place) Speciation speciation that occurs in geographically isolated populations s eparation due to different geographical events 4

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6. Reproductive isolation- Two group of individuals evolved from same parental population do not interbreed. 6

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8. Post zygotic reproductive isolation 8

9. Peripatric ( peri =near, patric =place) Speciation a  small subset  of a large population becomes isolated at the periphery of the original population's range Over generations, the small group becomes reproductively isolated from the original population. THIS TYPE OF SPECIATION ALSO KNOWN AS FOUNDER EFFECT 9

10. Parapatric ( para =beside, patric =place) Speciation Individuals are more likely to mate with their geographic neighbors. This also results in a reduced gene flow within the population no specific barrier to gene flow the mating behavior is NOT random 10

11. Example- 11

12. Sympatric ( sym =same, patric =place) Speciation a species splits into two groups that diversify and become  genetically isolated while remaining in the same place. 12

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14. Example- Polyploidy in plants 14

15. A uto polyploidy (chromosomes in the new species all from the same ancestral species) 15

16. A llo polyploidy (chromosomes in the new species come from two different (but related) ancestral species) 16

17. CONCLUSION 17

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19. THANK YOU 19