How is fish skin characterized compared to other animals' skin?

Fish skin is characterized as being thin and sensitive due to its unique structure and function. Fish skin consists of a single layer of epidermis and a thicker dermis underneath, which provides protection but is not as robust as the skin of many terrestrial animals. This thinness is essential for facilitating gas exchange through the skin, especially for species that utilize it as a supplemental respiratory surface.

Furthermore, fish skin contains mucous cells that produce a protective mucus layer, which helps in reducing friction while swimming and provides a defense against pathogens, emphasizing the sensitivity of the skin. This sensitivity also relates to the presence of sensory structures that are essential for their environment and behavior.

In contrast, the skin of other animals, particularly land mammals, tends to be thicker and more robust due to the need for greater protection against the elements and physical abrasions. Thus, the thin and sensitive nature of fish skin is a key adaptation for aquatic life, allowing for effective interaction with their environment.