By Don Pinnock - Daily Maverick While hunters celebrate and conservationists mourn the killing of two of Botswana’s largest-tusked elephants, a biodiversity tragedy is waiting in the wings. or millions of years, elephants have undertaken seasonal migrations, following the rains that nourish the foliage they eat. On the way, they refashion landscapes, fertilise the grasslands essential for countless herbivores and help sequester carbon by spreading seeds. One of their main dispersal routes as they move from the Okavango Delta and central Botswana is northwards along the Kwando River into...