Question

which evolutionary mechanism describes the formation of new species in neighboring but distinct habitats without physical barriers?
a. peripatric speciation
b. parapatric speciation
c. sympatric speciation
d. allopatric speciation
which of the following is an example of geographical isolation leading to speciation?
a. galapagos finches
b. cichlid fish in african lakes
c. apple maggot fly
d. greenish warbler
which example illustrates the concept of mechanical isolation?
a. insects with incompatible reproductive organs
b. fish in separate lakes
c. plants flowering at different times
d. different mating calls of frogs

Explanation:

• First question: Parapatric speciation occurs in neighboring but distinct habitats without physical barriers. Sympatric speciation occurs in the same area. Allopatric speciation requires physical barriers. There is no "Peripatric" or "Pripatric" speciation in standard evolutionary biology (likely typos, but if we assume options: sympatric is same area, allopatric is physical barrier - so if the description is neighboring no physical barrier - parapatric is the term. But if options have typo and assume intended "Parapatric" as a. then that's the answer.
• Second question: Galapagos finches had geographical isolation (different islands) leading to speciation. Cichlid fish in African lakes - sympatric (same lake, ecological etc. isolation). Apple maggot fly - sympatric (host plant shift). Greenish warbler - ring species (parapatric).
• Third question: Mechanical isolation is about incompatible reproductive organs (like insects). Fish in separate lakes - geographical. Plants flowering at different times - temporal. Different mating calls - behavioral.

Answer:

a. Parapatric speciation
a. Galapagos finches
a. Insects with incompatible reproductive organs