Which hypothesis of speciation does not call on the reinforcing process?
Sympatric speciation
Allopatric speciation
parapatric speciation
Peripatric speciation
Option (2)- Natural selection can improve the reproductive isolation between two populations of a species through a process called reinforcement. Reinforcement is an important condition for both the parapatric and sympatric hypotheses of speciation. Allopatric speciation does not involve the reinforcing process.
Hence, option 2 is the correct answer.