In some cases, the species are entirely dependent on each other (obligate mutualism) and in others, they derive benefits from their relationship but could survive without each other (facultative ...

A well-studied example of a ring species is the salamander Ensatina escholtzii of the Pacific Coast region of the United States. In Southern California, naturalists have found what look like two ...

1993). There are a number of other well-described examples where keystone species act as determinate predators. Sea otters (i) regulate sea urchin populations, which in turn feed upon kelp and ...

"The recovery of these species from near extirpation during the 1980s in New Jersey is a dramatic example of what is possible when regulations, science, and public commitment come together for a ...