sequence of events involved in the development of a species
For evolution to occur, an organism must be able to generate genetic variation—i.e., it must produce descendants that are genetically different from either parent.
The Gene
all the animal life in a particular region or period
A network of freshwater streams in the reserve supports a rich diversity of flora and fauna, including more than 1,000 species of flowering plants and over 500 species of animals. Reuters
the type of environment in which an organism normally lives
While the rain forest had more kinds of animals than any other habitat—with many species still undiscovered—they were often difficult to see.
Death on the River of Doubt
By contrast, a bulldog and a spaniel may look very different, but they are members of the same species, sharing the same DNA pool.
Sapiens: A Brief History of Humankind
the relation between two interdependent species of organisms
As my biological studies progressed, I became increasingly interested in symbiosis, the close relationships formed between unrelated organisms. Scientific American