Paul Enrlich gave the Rivet Popper hypothesis to explain the significance of the key species in functioning of an ecosystem. The hypothesis uses an aeroplane as an analogue to the ecosystem and the rivets of the airplane as species that join parts aeroplane together. Passengers are the human counter-part in anthropogenic activities. As per the hypothesis, if the passengers start removing the rivets, initially it will not have any impact of the flight capability of the plane but later, the plane will lose it flying capability. If the rivets of the wings are removed it directly affect the functioning of the plane. In the same analogy, if the key species are exploited and they get extinct, it will not harm the ecosystem initially but, eventually, it will lead to collapse of the ecosystem. The Rivet Popper hypothesis compares the rivets of the wings to the key species that helps in proper functioning and stabilising of the ecosystem.