Cookie use on MRCVSonline
We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive all cookies.
If you would like to forward this story on to a friend, simply fill in the form below and click send.

Your friend's email:
Your email:
Your name:
 
 
Send Cancel

Fish appear to recognise themselves in the mirror
Alex Jordan administered the mirror test on cleaner wrasse in order to test the cognitive capacity of social fish.

Study raises questions about how scientists test self-awareness in animals

Fish appear to be able to recognise themselves in the mirror, according to new research.

The study, published in PLOS Biology, observed cleaner wrasse fish responding to their reflection and attempting to remove coloured marks on their body.

The finding suggests that fish have higher cognitive abilities than first thought and has sparked questions about how scientists test self-awareness in animals that are so dissimilar to humans.

The research was carried out by researchers at the Max Planck Institute for Ornithology, the University of Konstanz and Osaka City University.

“The behaviours we observe leave little doubt that this fish behaviourally fulfils all criteria of the mirror test as originally laid out,” explained Alex Jordan, principal investigator at the Max Planck Institute for Ornithology and the University of Konstanz.

“What is less clear is whether these behaviours should be considered as evidence that fish are self-aware - even though in the past these same behaviours have been interpreted as self-awareness in so many other animals.”

In the study, scientists placed a coloured mark on fish in an area that could only be viewed in a mirror. To gain a ‘pass,’ the fish needed to touch or investigate their mark, showing an awareness of the reflected image.

The researchers witnessed the fish attempting to remove the marks by rubbing their bodies on hard surfaces after looking at themselves in the mirror.

The fish did not attempt to remove transparent marks in the presence of a mirror, nor did they attempt to remove the coloured marks when no mirror was present. This suggests that the fish were responding to the visual cue of seeing the mark on themselves in the mirror.

To the authors of the study, the results present clear evidence of behaviours that appear to pass every phase of the classic mirror test. What is not yet clear, however, is whether the evidence shows that fish possess self-awareness.

“Personally, I find the most parsimonious interpretation to be that these fish do pass the test as given, but this doesn’t mean they are self-aware,” Alex continued. “Rather they come to recognise the reflection as a representation of their own bodies without the involvement of self-consciousness.

“Given this, we should critically evaluate whether the mark test remains the gold-standard for awareness testing in animals.”

Image (C) Max Planck Institute/S.Gingins.

Become a member or log in to add this story to your CPD history

Veterinary Evidence Student Awards winners revealed

News Story 1
 The first winners of the RCVS Knowledge Veterinary Evidence Student Awards have been revealed.

Molly Vasanthakumar scooped first prize for her knowledge summary comparing the ecological impact of woven versus disposable drapes. She found that there is not enough evidence that disposable synthetics reduce the risk of surgical site.

Second prize went to Honoria Brown of the University of Cambridge, for her paper: ‘Can hoof wall temperature and digital pulse pressure be used as sensitive non-invasive diagnostic indicators of acute laminitis onset?’

Edinburgh’s Jacqueline Oi Ping Tong won third prize for critically appraising the evidence for whether a daily probiotic improved clinical outcomes in dogs with idiopathic diarrhoea. The papers have all achieved publication in RCVS Knowledge’s peer-reviewed journal, Veterinary Evidence.  

Click here for more...
News Shorts
Animal Welfare Foundation seeks new trustees

The Animal Welfare Foundation (AWF) seeks three new trustees to help drive the charity’s mission to improve animal welfare through veterinary science, education and debate.

Veterinary and animal welfare professionals from across the UK may apply, particularly those with experience in equine and small animal practice and research management. Trustees must attend at least two meetings a year, as well as the annual AWF Discussion Forum in London.

For more information about the role, visit www.animalwelfarefoundation.org.uk. Applications close at midnight on 13 August 2019.