Question

A. Briefly Define Allopatric speciation andlist one way that allopatric speciation can occur, providing an example

B. Briefly Define Sympatric speciation and list one way that sympatric speciation can occur, providing an example

Answer 1

A.allopatric speciation is that speciation which occurs when biological populations of same species become reproductively isolated from each other so that no gene flow occurs between them.

One way in which it occurs is when few organisms inhabiting in an are is separated from other organisms by formation of a river or valleys between them which physically separate them.

Example:Darwin's finches in Galapagos islands.

B.sympatric speciation is the evolution of a new species from already existing species while both are inhabiting the same geographical area.(reproductive isolation)

It occurs mainly by phenomenon of polyploidy in which the offsprings produced contains twice or thrice the number of chromosomes in parents.

Example:orca whales in Pacific Ocean, hawthorn fly.