Coloration of reef organisms
column spacer Coloration of reef organisms
  hot buttons for colours section of Biology of Caribbean Coral Reefs website
This section deals with the function of colours. Topics of HOW COLOURS ARE CREATED and HOW COLOURS ARE PERCEIVED can be accessed via the icons.

Function of colours

  Functions of colours and colour patterns in reef animals fall into 2 broad categories of SOCIAL and DEFENSE. Most or all of these topics have been mentioned elsewhere in the VIRTUAL DIVE but, by its nature, this section on COLOURS pulls them together in a broad summary. CLICK ON a topic to learn about it.

Function of colours: defense: induce confusion

seahorse dive leader for Biology of Caribbean Coral Reefs photograph of Caribbean snappers taken from a video

"Here I am, a voracious predator, coming up on a shoal of grunts. Who will I attack? Hmmm! All the mixed colours does make it quite confusing...maybe I'll try again later." - Turks & Caicos 2005

NOTE Haemulon spp.

A predator, much like our seahorse dive leader, but not acting so silly, coming up on a school of snappers may be confused not just by the shifting movements of the school, but by its changing colours, which can be quite bewildering.



photograph of shoal of blue-striped grunts
Stripes or other distinctive patterns of markings in schooling or aggregating species may act to confuse a predator.






Mixed school of grunts, predominantly
bluestriped grunts Haemulon sciurus, with
possibly some margates H. album 0.1X


photograph of different colour-morphs of Christmas-tree worms
Differently coloured adult individuals in a species, a type of polymorphism, is thought to be advantageous in that it makes it more difficult for a predator to form a search image for the entire species.

NOTE lit. "many shapes", resulting from different physical expression of the same or similar genes in different individuals of a species




Different colour morphs of Christmas-tree worms
Spirobranchus giganteus
may present a confusing
and hard to remember array for a predatory fish 0.25X

  This at first seems a sensible explanation, because worm-eating reef fishes have excellent colour vision and they do hunt by sight. However, they also have good smell- and vibration-receptors and these are likely also employed by the fishes to identify the worms as prey. Also, if predators exist that hunt after dark for the worms, colour morphs and colour-perception would not be factors.
hot button for how colours are created part of BCCR hot button for how colours are perceived part of BCCR hot button for functions of colours part of BCCR