Amongst the animal groups given below, which one has the highest percentage of endangered species?
Amongst the animal groups, amphibians appear to be more vulnerable to extinction. More than 15,500 species world-wide are facing the threat of extinction. Presently, 12 per cent of all bird species, 23 per cent of all mammal species, 32 per cent of all amphibian species and 31per cent of all gymnosperm species in the world face the threat of extinction.