PICKY EATERS Genetic analysis has revealed that ancestral bedbugs, like their modern relatives, probably preyed upon birds and small mammals, like this bat. In this image, a bedbug comes face-to-face with its prey.

DOG BREATH  Some Norwich terriers’ breathing troubles might rest on a mutated gene linked to swelling around airways, researchers suggest. The gene may also contribute to the labored breathing of dogs with flatter snouts, such as French and English bulldogs.