Environment shapes UV markings in reef fish - this is how they “talk” to each other
Most animal patterns are a compromise between conspicuousness for effective communication, and camouflage to avoid the attention of predators. The UV markings on reef fish are no exception.
Australian researchers showed that juvenile Ambon damselfish (Pomacentrus amboinens) develop their UV facial patterns in their first two weeks. Surprisingly, the development of these markings is not hard-wired, but instead highly plastic.
In fact, the UV markings did not develop in captivity - only when juveniles experience the socio-behavioural conditions of their natural environment. Because the markings are shaped by competitive and cooperative interactions and risk-taking behaviour, they may communicate important environmental information like predation risks.
- Damselfish face images converted into grey-scale images and then binarised to determine the number and size of white areas.
- Reference (Open access): Gagliano et al. 2015.
Facing the environment: onset and development of UV markings in young fish. Nature
- University of Western Australia News