Q.Extinction of a keystone species led to loss of biodiversity - Justify.

Step 1. The chapter defines coextinction as 'the loss of a species as a consequence of the extinction of another' — a direct cause-and-effect relationship between two ecologically linked species.

Step 2. The clearest chapter example is the Calvaria tree of Mauritius and the now-extinct Dodo bird: the Calvaria tree's seeds have a tough, horny endocarp that must be worn down before it can germinate, and this happened naturally when a Dodo swallowed the seed, with the large stones and digestive juices in the bird's gizzard making the endocarp permeable enough for easier germination.

Step 3. Once the Dodo went extinct, that essential step in the Calvaria tree's own life cycle disappeared with it, placing the tree itself in imminent danger of coextinction — demonstrating that a keystone relationship's loss removes not just the extinct species but its ecological function for other species too. …

Define coextinction and justify it using the chapter's Dodo-Calvaria tree mutualism example, which sh …

• Describing coextinction only in the abstract without citing the chapter's specific Dodo-Calvaria tree mechanism. …