Fish

When a behavioral ecologist gazed towards a group of emperor chichlids in Zambia recently, the fish seemed to be more alert and aggressive. That got him investigating whether they could really tell when they were being stared at.

The warm waters of Mexico and Texas are home to a small fish that has produced nothing but daughters for over 100,000 years. The offspring are the exact genetic copy of their mother, with no father involved. This is the amazing Amazon molly.

Researchers have identified a hybrid photoreceptor in the eyes of fish that carries traits of both rods and cones – a combination that doesn’t fit either category. It suggests the retina may be far more flexible than scientists have long assumed.

Omega-3 fatty acids sourced from wild-caught fish stocks are valued for their studied health benefits, but this has resulted in a reduction in fish stocks. A Scottish firm is working on a solution, in the form of omega-3s made from whisky waste.

In 1995, divers first noticed a group of bizarre sandy "crop circles" on the seabed near southwest Japan. But it took decades for scientists to identify the marine artists behind them – and why they were building such geometrically precise structures.

When you're checking the freshness of a piece of fish that you plan on eating, you want results right away. That's where a new microneedle-based sensor comes in, as it delivers a yay or nay in less than two minutes.

The water leaving your washing machine may soon be a lot more eco-friendly, thanks to the anchovy. A filter inspired by the tiny fish could remove microplastics from the outgoing water, keeping them from entering local waterways.

Oceanic manta rays make extreme dives of more than 1,200 meters – three-quarters of a mile – but it's not to feed. Instead, the mantas are calibrating their own kind of Google Maps as soon as they find themselves out beyond the continental shelf.

A study examining nearly 1,500 river sites in the US between 1980 and 2022 has shown that river heatwaves are happening up to four times faster than air heatwaves and lasting nearly twice as long. The finding has major implications for aquatic life.

The Remora fish has an oval slatted disc on its head which it uses like a suction cup to stick to sharks. It's inspired a capsule-sized platform that can stick to surfaces when submerged in liquids, including your digestive tract.

Back in 2014, we heard about a so-called "salmon cannon" that safely shot spawning fish up over river-blocking obstacles such as dams. Its successor has since entered use, recently allowing herring to bypass a spillway for the first time in 80 years.

A benzodiazepine seeping into waterways is causing young Atlantic salmon to behave strangely, with fish in the wild migrating more rapidly and taking more risks on their journey from river to ocean. It even seems to be messing up their social lives.