Earwigs Sniff Out Best Babies
Perhaps you remember your mother lovingly telling you and your siblings that she had no favorites and loved you all equally. Little did you know you really dodged a bullet by being born to a human mother and not a coldhearted, shrewd earwig mom.
In earwig nation, the idea of unconditional maternal love isn't a given. When earwig mothers have a clutch of babies (or nymphs), the mothers will sniff out a chemical signal from the healthier ones and proceed to provide more abundant care and feeding to those babies. The babies that are identified as hungrier and less robust will be given less attentive parenting and feeding [source: Gill].
So is this strange animal behavior nothing more than cold cruelty? Scientists point out that there are some really compelling reasons that earwig moms zero in on healthier nymphs. One, they have a lot of babies (30-60 at a time), so mortality is unavoidable. And naturally, focusing their efforts on more viable offspring makes a lot of sense -- no matter how nasty it might seem to the hungry earwig nymph.