Fish prove every pregnancy is a battle: Unexpected evidence for the food fight between mothers and babies
Left to their own devices, babies in the womb would suck their mothers dry. A developing baby benefits from taking as many essential nutrients as possible, but evolutionary theory predicts that to survive pregnancy, mothers need to keep some of these nutrients for themselves.
We haven't written up this one. Phys.org has the full story — the link below goes straight to it.