Earwig mothers sniff out their "best" offspring and lavish them with care, according to new research. The insects pick up odours from their clutch of "nymphs" and adjust their maternal behaviour in response. When they pick up a chemical signal from healthy, well-fed youngsters, they spend more time nursing them, at the expense of their hungrier babies. The study, which is the first to show this behaviour in insects, is published in Proceedings of the Royal Society B. Earwig parenting, it seems, is about favouritism; the standard of care drops dramatically when mums pick up the chemical signals from hungry,...