I think it the answer could be a "steamy mixture of carbon dioxide and water vapor".
Answer:
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
Answer:
The classification scheme is ancestor.
Explanation:
In cladistic approach is a type of classification in which organisms are classified on the basis of their common ancestor. Those organisms are placed in one group which have common ancestor and share same characteristics or which are evolved from a common ancestor. With the passage of time changes occurs within the body of organisms so these organisms are different from one another in physical structure but have a common ancestor.