Organisms Without Brains Can Learn, Too--So What Does It Mean to Be a Thinking Creature?

The brain is an evolutionary marvel. By shifting the control of sensing and behavior to this central organ, animals (including us) are able to flexibly respond and flourish in unpredictable environments. One skill above all--learning--has proven key to the good life. But what of all the organisms that lack this precious organ? From jellyfish and […]