This Fish's Brain Is Larger Than Yours (IMAGE) Washington University in St. Louis Caption The brain of Gnathonemus petersii is larger in proportion to its body than a human's. To keep up with the energy demands of its big brain, it has evolved a Schnauzenorgan, a chin appendage covered with electroreceptors that helps it locate prey (calories). Credit David Kilper/Washington University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.