Mothers can teach their children much about the world, but some mothers can do it without ever meeting their young. Take the field cricket Gryllus pennsylvanicus. A female cricket isn’t exactly a caring mother. Once she lays her eggs, she abandons them to their fate. But amazingly, she can also forewarn her young of the dangers they might face. If a pregnant female is exposed to a wolf spider, her experiences affect her unborn young. When they hatch, the baby crickets are more likely to freeze when they smell wolf spiders nearby. Cricket.jpgIf mothers sense a threat in their environment, there are clear advantages in being able to prepare her young to face those threats. Over the last decade or so, scientists have discovered that many animal and plant mothers do exactly this, even before their young are born. If pregnant water fleas are exposed to the smell of a predatory midge, they produce young that are armed with larger ‘crowns-of-thorn’, defensive spiky helmets that make them difficult mouthfuls. In the same way, aphids produce more winged offspring if they sense danger. Even the humble radish can generate a generation with sharp, spiky hairs. In all of these […]