Belle Benchley was the first director of the San Diego Zoo. She revolutionized zoo-keeping by insisting that, in every decision, the animals come first. She made sure that all animals had private enclosures they could return to when being in the public eye stressed them out, and that the zoo kept a permanent veterinary staff on hand. Under her directorship, animal lifespans dramatically lengthened and the zoo evolved from a place of cruel entertainment to one of enlightened education. You can read her full story (part of MAL’s Women in Science series) here.