Cephalopod Pseudomorph Function

Richard E. Young and Katharina M. Mangold (1922-2003)

Cephalopoda Glossary

Ink is used in a variety of ways by cephalopods. One way is to use the ink to create a pseudomorph (false form). To make a pseudomorph the ink is mixed with mucous apparently from the funnel organ. The funnel organ lies on the inner walls of the funnel. The ink mass then is squirted out through the funnel into the sea water. The mucous mass holds the ink withinin a confined region. If just the right amount of ink and mucous are ejected, the dark mass will have approximately the dimensions of the squid that secreted it.

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While no experimental evidence has demonstrated the function of the pseudomorph, any diver that has been confused by this behavior will have little doubt as to its function. The swimming squid detects the approach of a diver (or predator) and suddenly expands its chromatophores to become very dark. It then secretes a pseudomorph, pales in color and rapidly darts away. Even if the diver is aware of this trick from previous experience, he/she automatically visually locks onto the dark mass while the squid "vanishes."


About This Page

University of Hawaii, Honolulu, HI, USA

Katharina M. Mangold (1922-2003)
Laboratoire Arago, Banyuls-Sur-Mer, France

Page: Tree of Life Cephalopod Pseudomorph Function Authored by Richard E. Young and Katharina M. Mangold (1922-2003). The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

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