A two-month-old Asian elephant named Linh Mai, or "spirit blossom" in Vietnamese, made her public debut at the Smithsonian National Zoo in Washington, D.C. on Earth Day. The zoo had to separate her from her mother, Nhi Linh, after she showed signs of aggression towards the calf. Another elephant, Swarna, has taken over the maternal role as a surrogate aunt and is teaching the calf the art of using her trunk. The plight of Asian elephants, which are endangered by losing their habitat and slow population growth due to their long gestation period and need for prolonged nurturing of their young, is also a concern. The World Wildlife Fund estimates that there are only an estimated 30,000 to 50,000 in the wild, with their population dropping by about 50% over the last 60-75 years.