Ascidians

Ascidians are exclusively marine animals that belong to the group of tunicates. Despite their particular external appearance, which makes them hard to recognize as animals to an untrained eye, tunicates are the closest living beings to vertebrates from an evolutionary standpoint. This means they share several anatomical and physiological traits with vertebrates. Ascidians constitute the most numerous group of tunicates in terms of species count. They are sessile animals that live attached to rocks or other hard substrates, filtering seawater to capture small organisms and organic particles suspended in the water, which serve as their food. To do this, they use the first part of their digestive system, which is equipped with small pores.

The NoDe project aims to study the effects of noise exposure on a specific organ, the coronal organ, located on the tentacles near the mouth. The coronal organ consists of specialized sensory cells, known as hair cells, which are structurally similar to the sensory cells found in the inner ear of vertebrates.