While fish are primarily known for breathing through their gills, some species can also absorb oxygen through their skin, a process known as cutaneous respiration.
This is especially important for:
- Developing fish: Many young fish breathe exclusively through their skin before their gills fully develop.
- Mudskippers: These amphibious fish can breathe air through their skin and the lining of their mouth and throat when out of water.
- Hagfish: These primitive fish can absorb oxygen through their skin while buried in mud.
However, for most fish, cutaneous respiration is a supplementary means of oxygen intake, not the primary one. Their gills are specifically adapted to efficiently extract oxygen from water.
