How does a ring species illustrate speciation in action?

Speciation occurs at terminal population groups

Explanation:

A ring species represents a group of organism that has moved beyond a geographic barrier to produce a ring shaped distribution. This population is contiguous and there exists no barrier to gene flow anywhere in the ring except at the terminal populations.  

Speciation is demonstrated in the terminal population has become sympatric and it does not interbreed even if they are connected by chain of intergrading or interbreeding populations

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation:

not too sure but maybe in the hot springs.