When you and I take a deep breath, we pull air into our lungs. That’s because humans are mammals. But fish aren’t mammals. They usually don’t breathe air. They usually don’t have lungs. That’s what I ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. The human outer ear may have arisen from ancient fish gills. | Credit: A. Martin UW ...

In trout, researchers have discovered that a particular type of primitive antibody is essential for fighting microbes that cause disease while preserving others that make up a healthy microbiome.

Chronic exposure to microplastic fibers causes aneurysms, erosion of surface layers and other serious damage to fish gills, and increases egg production in female fish, a sign that chemicals in the ...

We can be guilty of thinking that oxygen is a uniquely human need. While all land-dwelling animals breathe oxygen from the air, fish need oxygen too. Not only this, but fish can run out of oxygen, ...