Invasive species are a global threat because they can outcompete many native species and lower the biodiversity of entire ecosystems.

(a) Maintaining high global biodiversity is important to provide ecosystem services to humans. Describe one cultural ecosystem service provided by diverse ecosystems.

(iii) Many ecologists argue that establishing large preserves is the single best strategy for preventing an endangered species from becoming extinct. Justify this strategy by explaining an additional benefit, other than preventing the endangered species from becoming extinct.