According to a recent study, bird species with unusual or severe combinations of features are most at risk of going extinct. The results are presented in the journal Functional Ecology by the British Ecological Society. The most distinctive birds on the planet, according to a recent study done by scientists at Imperial College London, are also the most endangered. The loss of these species and their distinctive ecological functions, such as seed dispersal, pollination, and predation, could negatively impact ecosystem health. The study, which is the most thorough to date, examined the extinction risk and physical characteristics (such as wing length and beak shape) of 99 per cent of all living bird species. The scientists discovered that there would be a noticeably greater reduction in the physical (or morphological) diversity among birds in simulated scenarios were all threatened and near-threatened bird species went extinct than in scenarios where extinctions were random. The Christmas Frigatebird (Fregata andrewsi), which only breeds on Christmas Island, and the Bristle-thighed Curlew (Numenius tahitiensis), which makes an annual migration from its breeding grounds in Alaska to South Pacific islands, are two bird species that are both morphologically distinctive and endangered.