What can a biodiversity index or survey indicate about an ecosystem's health and resiliency to change?

Sometimes, when one species is removed, the ecosystem does not respond in such ... role of biodiversity in ecosystem resilience using the metaphor of the house of cards. ... We can hope that climate change will be relatively mild and easy to adapt to. ... It is not the intent of this course to tell you what your views should be.

Explanation:

I think it is: Lithosphere is formed by frequent volcanic eruptions along the length of mid-ocean ridges and is pushed outward from them gradually.