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 ...

Fish live surrounded by water, so the idea that they might struggle to breathe sounds wrong at first. It feels like asking ...

Scientists have traced the evolutionary origin of humans' outer ears to the gills of ancient fish through a series of gene-editing experiments. When you purchase through links on our site, we may earn ...