Nowadays, the main part of plants and the totally of mammals present in French Polynesia were introduced by man.

Biodiversity is very low in French Polynesia. Indeed, insect biodiversity of Takapoto atoll is in a ratio of 1:5 compared to Arno atoll (Marshall Islands) and in a ratio of 1:100 compared to Australia. The Madrepora diversity is 3 times lower in Tuamotu than in the Great Barrier Reef and the mollusk diversity is 8 times lower in Tuamotu than in the west Pacific.

Some species of mollusk can be very abundant in closed atolls and dominate the biomass, like pear oyster and benitiers.