Mirror test hints at cognitive abilities in fish

WASHINGTON: A small tropical reef fish was able to recognise itself in a mirror, scientists said in a finding that raises provocative questions about assessing selfawareness and cognitive abilities in animals.

The study involved experiments in which the fish species Labroides dimidiatus, called the bluestreak cleaner wrasse, was given a mirror self recognition test, a technique developed in 1970 for gauging animal selfawareness.

In aquarium experiments at Osaka City University in Japan, the researchers applied a browncolored mark on the fish’s body in a place that could be seen only in a mirror reflection.

The fish they did this to tried to remove the marks by scraping their bodies on hard surfaces after watching themselves in a mirror, but never tried to remove the brown marks without a mirror present, indicating they understood the reflection was of them, the researchers said.

When a transparent, rather than brown, mark was applied, the fish never tried to remove it.

PHOTO: REUTERS Check this out . . . A cleaner wrasse interacts with its reflection in a mirror placed on the outside aquarium glass at a laboratory in Konstanz, Germany.