Question

Sympatric speciation develops reproductive isolation without
A. Geographic barrier
B. Barrier to mating
C. Barrier to gene flow
D. Genetic change

Answer 1

Hint: The sympatric speciation occurs when the two groups of the same species live in the same geographic location but can evolve differently until they are no longer interbreed and considered different species.

Complete answer:
Speciation is the process by which a new species is created. There are five types of speciation and one of the types is sympatric speciation. It arises when there are no physical barriers such as waterway or mountain range, etc. This speciation occurs through polyploidy and therefore is rare in animals than plants because in plants self-fertilization is more common than in animals. A normal chromosome has two copies of each chromosome i.e. diploidy but in polyploidy, the number of chromosomes is more than two copies. A sympatric speciation example is apple maggot. This insect lays eggs in apple fruit and causes rot. They originally laid eggs in a relative fruit of the apple called hawthorn. When apples were introduced in North America in the 19th century, a maggot developed that lays eggs in apples, and when both species were compared then it was found that the maggot species laying eggs in hawthorn and in the apple belongs to the same species. Therefore, sympatric speciation is believed to occur in these cases.
Hence, the correct answer is option A. Geographical barrier.

Note:A reproductive isolation of a subpopulation from the parental population leads to the formation of species without geographical isolation, such species are symmetric speciation.