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1. LUCKNOW UNIVERSITY
Internal assessment
M.Sc. semester – III
Topic - Mechanisms of speciation
Submitted to-
Department of zoology
Isabella Thoburn college
Lucknow.
Submitted by-
Name – Sneha Manjul
Class – M.Sc. Semester III
Roll no – Z/22/19
Session – 2022- 2023

2. INDEX
SERIAL NO. TOPIC PAGE NO.
1 INTRODUCTION 3-4
2 ALLOPATRIC SPECIATION 5-9
3 PERIPETRIC SPECIATION 10
4 PARAPETRIC SPECIATION 11-12
5 SYMPATRIC SPECIATION 13-15
6 AUTOPOILDY 16
7 ALLOPLOIDY 17

3. Mechanism of speciation

4. Modes of speciation
• ALLOPATRIC SPECIATION
• REPRODUCTION ISOLATION
• PERIPATRIC SPECIATION
• SYMPATRIC SPECIATION
• PARAPATRIC SPECIATION

5. 5
Allopatric (allo=other,
patric=place) Speciation
• speciation that occurs in geographically isolated
populations
• separation due to different geographical events

7. 7
Reproductive isolation-
Two group of individuals evolved from same
parental population do not interbreed.

8. 8

9. Post zygotic reproductive isolation

10. 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 SPECIA
TIONALSO
KNOWNAS FOUNDER EFFECT

11. 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

12. Example-

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

15. Example-
Polyploidy in plants

16. Autopolyploidy (chromosomes in the
new species all from the same ancestral
species)

17. Allopolyploidy (chromosomes in the new
species come from two different (but
related) ancestral species)

18. CONCLUSION

19. THANKYOU