What killed hundreds of elephants in Botswana?

Botswana’s government says it still doesn’t know what caused the deaths of hundreds of elephants in recent weeks, but testing continues.

Poaching and anthrax have been ruled out as the likely cause. Other possibilities being examined include a novel virus and poisoning. The investigation involves help from laboratories in South Africa, Zimbabwe, Britain and the United States.

“While there has not been any indication of fresh carcasses or signs that the mortality has spread beyond the initial area of concern, the district team on the ground will continue to monitor the situation, remove ivory…