In the lobby of a Florida Atlantic University research building, there is a fish tank divided in two. On one side are fish without eyes, pale pink in color. On the other side are normal looking fish, silvery gray with black eyes. The plaque, however, identifies them both as Astyanax Mexicanus. The pale fish lives in subterranean caves in Mexico beneath the eyed river fish.

Understanding how the same fish can look so different is a question that scientists have been investigating for over 80 years. Today, upstairs, and in labs around the world the Mexican cavefish is also a model to study genetics, disease, and neuroscience. They are obese, have diabetes, and do not sleep much. Scientists are studying why these qualities, considered maladies in people, seem to help these fish thrive in the dark.

The cavefish’s story includes jungle explorers braving plane crashes and venomous snakes to find it and the scientists who studied it. They include a renowned German professor who fled Nazi Germany and a female Turkish scientist, Perihan Sadoglu who did some of the first genetic work in the 1950’s, but who mysteriously disappeared mid-career.

Today the cavefish is a model to study genetics and also neuroscience and disease. As the fish's story continues today, a mystery of the past is revealed.

Perihan Sadoglu was one of the first scientists to study cavefish genetics. Today scientists are building upon her work and others to better understand the fish's curious characteristics.