Speciation and Reproductive Isolation Quiz

Speciation

• The process of forming new species from a species already in existence.

• The process of extinction of a species due to environmental changes.

• The process of adaptation of a species to its environment over time.

• The process of migration of species to new habitats.

When the original population splits into two isolated groups

• The groups begin to breed among themselves, and genetic changes accumulate over time.

• The groups merge back into a single population.

• The groups become extinct due to lack of resources.

• The groups develop identical genetic traits.

Example of mechanical isolation

• Two species of orchids have differently shaped flowers that only allow specific pollinators to access their nectar, preventing cross-pollination.

• Two species of birds that mate at different times of the year, preventing them from interbreeding.

• Two species of frogs that have different mating calls, attracting only their own kind.

• Two species of plants that grow in different habitats, preventing them from coming into contact.

What is sympatric speciation?

• A process where new species evolve from a single ancestral species while inhabiting the same geographic region.

• A type of speciation that occurs due to physical barriers separating populations.

• A form of speciation that happens when two species interbreed and produce fertile offspring.

• A method of species formation that requires different environmental conditions for evolution.

An example of temporal isolation in plants

• Certain plants could theoretically breed with each other, but they flower at different times of the year.

• Certain plants have different pollinators that prevent them from breeding.

• Certain plants have different leaf shapes that prevent them from breeding.

• Certain plants are located in different geographical areas that prevent them from breeding.

*Tradescantia ohiensis*, a plant also known as bluejacket and its relative, *T. subaspera* have similar reproductive mechanisms but do not mate, as one species lives in sun while the other lives in shade. What is this phenomenon called?

• behavioral isolation

• temporal isolation

• geographical isolation

• mechanical isolation

When two populations no longer breed with each other

• Reproductive isolation has occurred.

• Genetic drift has occurred.

• Natural selection has occurred.

• Speciation has occurred.

Example of ecological isolation

• Two species of birds may live in the same area but occupy different habitats, such as one living in the treetops and the other on the forest floor, preventing them from mating.

• Two species of fish that live in the same ocean but feed at different depths, thus avoiding competition.

• Two species of frogs that breed in different seasons, preventing them from mating even if they live in the same pond.

• Two species of plants that grow in the same region but have different pollinators, leading to reproductive isolation.

What is hybrid sterility?

• A condition where hybrid offspring can reproduce successfully.

• A phenomenon where hybrid offspring are produced but are sterile, such as a mule.

• A genetic mutation that enhances reproductive capabilities in hybrids.

• A type of reproductive isolation that occurs only in plants.

A type of isolation in which two populations with complex courtship displays or rituals become different enough that they no longer respond to the other’s actions.

• behavioral isolation

• temporal isolation

• geographic isolation

• mechanical isolation