Cleaner shrimp are the dental hygienists of the reef. They pick parasites, food scraps and dead skin off passing predators, even climbing into their mouths without, somehow, getting eaten. It turns out that this is the result of a multi-stage negotiation between shrimp and predator. If the shrimp wants a meal, it waves its antennae in the air as a fish approaches, and if the fish wants to be cleaned, it goes a darker colour. Unless both of these things happen, cleaning doesn’t usually occur, indicating that this is an inter-species signaling process. Via Eurekalert!
Zebrafish have an advanced ability to see the world, with 360-degree vision to watch for predators and the skill to see barely-visible prey (mostly single-cell animals) by detecting changes in UV light. If humans had eyes as large as the zebrafish, each eyeball would be the size of a large grapefruit. Via ScienceDaily
Over the past thirty years, over-fishing, pollution and climate change have kno