Microbiologists and fish researchers have discovered an entirely new type of symbiosis: bacteria in the gills of fish that convert harmful ammonia into harmless nitrogen gas. Fish produce a lot of ...

A collaborative team of scientists recently found that there is no physiological evidence supporting a leading theory -- which involves the surface area of fish gills -- as to why many fish species ...

The outer ear is unique to mammals, but its evolutionary origin has remained a mystery. According to a study published in Nature from the USC Stem Cell lab of Gage Crump, this intricate coil of ...

Gill evolution Fish gills evolved to balance pH, not breathe, suggests a new study. This goes against the traditional assumption that gills first evolved so fish could get more oxygen as they became ...

Evolution is a master recycler. It often uses old structures (or ancient genes) for new jobs. The mammalian ear is a perfect example. Over the eons, the jawbones of our fish ancestors became three ...