Cave and deep-sea fish, which also include salmon herring (Maurolicus muelleri, photo), are optimally adapted to the low-light environment in which they live: most species have only light sensory cells in their retina, the light-dark perception are specialized and already activated at low light intensity, so-called rods. Sensory cells for color perception, which are only active at higher light intensity, so-called cones, have often been lost in the course of evolution. Some species are even without eyesight. Salmon herring are also known as deep-sea fish, but they are not enough for them. They live in water depths, into which only little light penetrates, but for food search they come up during the dusk. Her eyes are perfectly adapted to life with changing light intensity - A new kind of light-sensing cell recently discovered by University of Queensland scientists in the salmon herring retina makes it possible:
In the salmon herring retina, the team found a single type of receptor, which is typical of deep-sea fish. Because of the shape, the researchers initially considered these light receptors to be chopsticks. But a closer analysis of the cells showed that they also had properties of cones. "Our results help to understand the evolution of vertebrate organs a little better, " says Fanny de Busserolle from the research group. The results of the study were published in the journal Science Advances.
Photo: Dr. Wen-Sung Chung / University of Queensland© science.de - Ruth Rehbock / Jana Burczyk advertisement