This insect's unique reproductive biology could lead to new ways to control the species in the environment – and prevent the deadly sleeping sickness it spreads to people.
Mud blister worms make their homes in the shells of oysters and other shellfish, where they weaken their hosts.
Fish can't read maps, and their eggs and larvae drift across national boundaries. Recent research shows that local problems in one fishery can affect others across wide areas.
Progress against malaria has stalled. There's been an increase in the number of cases reported since 2015.