LifeOrcas are bringing humans gifts – what does it mean? Researchers have documented orcas seemingly gifting rays, seals and fish to scientists and divers, which could suggest they have theory of mind and engage in altruism – even across species News
HealthTB's extraordinary evolution reveals why the ancient disease lives on Once thought to have originated in cows and spread through dust, the surprising evolutionary story of tuberculosis reveals why it's so hard to stamp out this ancient disease, writes Carl Zimmer Features