Co-Extinction of Host Species and Parasites

Co-extinction refers to the simultaneous extinction of two or more species that are dependent on each other for survival. In the case of host species and parasites, the extinction of one species can lead to the extinction of the other. When a host species dies off, its unique parasites also die off as they no longer have a viable host to live on. This phenomenon is known as co-extinction.

Explanation of the Correct Answer

The correct answer to the given question is option 'B' i.e. co-extinction. This is because when all the members of a host species die, the unique parasites that depend on the host for their survival are also likely to die off. This can have serious consequences for the ecological balance of the ecosystem as parasites play an important role in regulating the populations of their hosts and other species in the food chain. Co-extinction can also lead to the loss of important genetic diversity and the extinction of other species that depend on the host-parasite relationship.

Other Options Explained

(a) Biological control: Biological control refers to the use of natural enemies like predators, parasites, and pathogens to control the populations of pests or invasive species. This option is not relevant to the given question as it does not relate to the extinction of host species and their parasites.

(c) Conservation: Conservation refers to the protection and management of natural resources and biodiversity. While conservation may help to prevent the extinction of species, it is not directly related to the phenomenon of co-extinction.

(d) Extinction: Extinction refers to the complete disappearance of a species from the Earth. While the extinction of a host species can lead to the co-extinction of its unique parasites, this option is too broad and does not specifically address the relationship between host species and parasites.

Conclusion

Co-extinction is a serious threat to biodiversity and ecosystem stability. It is important to recognize the interdependence of species and to take steps to protect and conserve them.