In the crushing, high-pressure environment of the abyssal plain, traditional vertebrate anatomy—characterized by rigid skeletons and gas-filled swim bladders—becomes a liability. The blobfish, Psychrolutes marcidus , represents a masterclass in evolutionary compromise. Lacking the dense bone structure of its shallow-water cousins, its body is composed primarily of a gelatinous mass with a density slightly less than that of water. This unique composition allows the blobfish to maintain neutral buoyancy without the energetic expense of active swimming. Its skin is loose and flaccid, lacking the structural integrity required to hold a shape under atmospheric pressure, which leads to its iconic, sagging appearance when removed from the deep sea. In its natural habitat, however, the water pressure provides the necessary support to maintain its streamlined, albeit soft, profile. ...