A key stone species is the most crucial part of an ecosystem and without keystone species all the food webs with in an ecosystems or its surrounding niche remains incomplete. These species may not be the most populous or powerful but are definitely important for the survival of all other species in the ecosystem. In option A, the species is considered important as it has a positive impact on all species thus in its absence the health of all species would be adversely impacted.
Explanation: You can see that the green colored frogs were once lower than the blue and as time started progressing the green started getting a higher population over the blue, as the blue decreased.
This is comparable to the impression of the 'sneaky' males
in the side-blotched lizard. Natural section favor an individual by the detector
or sensor will sustain less cost and increase an advantage and gain over others
incapable to distinguish the deceitfulness.
