Family quarrels in seeds reveal the ways parents and offspring sometimes evolve in conflicting directions

It's spring, finally—and in the tree branches a battle is brewing. A robin returns to her nest with an earthworm. Her nestlings all beg, but only one will get this meal. And while Mom has an interest in making sure that all of her babies thrive, each little bird is more selfish. So the baby opens his beak again and again: give me more! Now picture a similar clash playing out in flowers of the same tree. A new study from Washington University in St. Louis reveals the surprising way that family quarrels in seeds drive rapid evolution. Researchers in Arts & Sciences discovered that conflict over the amount of resources an offspring receives from its parent seems to play a special role in the development of certain seed tissues. The study will be published the week of April 22 in the Proceedings of the National Academy of Sciences. Plant seeds contain tissues that represent three distinct genetic relatives: the mother, the embryo and a bizarre triploid tissue called the endosperm that is involved in nutrient transfer from mother to embryo.