icon bookmark-bicon bookmarkicon cameraicon checkicon chevron downicon chevron lefticon chevron righticon chevron upicon closeicon v-compressicon downloadicon editicon v-expandicon fbicon fileicon filtericon flag ruicon full chevron downicon full chevron lefticon full chevron righticon full chevron upicon gpicon insicon mailicon moveicon-musicicon mutedicon nomutedicon okicon v-pauseicon v-playicon searchicon shareicon sign inicon sign upicon stepbackicon stepforicon swipe downicon tagicon tagsicon tgicon trashicon twicon vkicon yticon wticon fm

Feisty fish pee to convey aggression to rivals – study

Feisty fish pee to convey aggression to rivals – study
At least one species of fish communicates aggression using chemicals found in its urine, scientists in Switzerland have discovered in an experiment to uncover behavioral habits.

Researchers at the University of Bern conducted experiments on the cichlid fish of various sizes and studied how they interpreted urine signals to convey aggressive or submissive behavior.

Scientists already believed that fish urinated in moments of aggression, but up to this point it had not been known that urine is used as a behavioral signal.

READ MORE: Rescuers save desperate whale trapped in massive fishing net (VIDEO)

The study, published in the Behavioural Ecology and Sociobiology journal, involved tanks being set up with a partition between the fish to prevent physical interactions and then adjusted for the experiments.

It was discovered that the frequency of urination was significantly higher when two fish could see each other but were separated within a tank, apparently aware that their message was not being received.

Fish displayed aggressive actions but, when chemicals were successfully transmitted, the smaller fish reduced its aggressiveness, surrendering to the larger one.

Fish were injected with a violet blue dye to allow the volume of urine expelled to be seen and measured, and then pairs were subject to a series of scenarios of varying visual and chemical contact.

Other animals use chemical cues to communicate for various reasons, from bonding and mating to territorial and social ranking markings.

Dear readers and commenters,

We have implemented a new engine for our comment section. We hope the transition goes smoothly for all of you. Unfortunately, the comments made before the change have been lost due to a technical problem. We are working on restoring them, and hoping to see you fill up the comment section with new ones. You should still be able to log in to comment using your social-media profiles, but if you signed up under an RT profile before, you are invited to create a new profile with the new commenting system.

Sorry for the inconvenience, and looking forward to your future comments,

RT Team.