Groups of similar individuals that can interbreed freely and produce fertile offspring are referred to as:

The separation of a group of organisms by a geographical barrier resulting in the differentiation of the original group into new varieties or species is referred to as:

In allopatric speciation, the evolution of new species is brought about by geographic barriers. Meanwhile, in sympatric speciation, ____ is the most common factor that leads to species divergence.

The theory that states that evolution happens through a short burst of an intense speciation event followed by a lengthy period of no morphological change is called __________.  

From a single species, finches in Galapagos Island have evolved and diverged into a large variety due to the presence of new habitats. This is considered as: