Octopus Body Pattern Display Signals Before Octopus Fights or Flights

Summary: A diver in Australia, a marine biologist in Alaska, and a philosopher in New York describe octopus body pattern display signals before fights or flights.

Fight signals -- Octopus displays dark color and outspread web and arms: David Scheel, usage restrictions: credit required, via EurekAlert!

Octopus body pattern display signals are challenging familiar views of octopuses as camouflage-fixated loners that meet for cannibalism or mating, according to research published Jan. 28, 2016, in the online Current Biology.

The three co-authors base their findings upon 186 interactions, 345 body patterns and 512 actions recorded in 52.8 hours of video taken in Australia’s Jervis Bay. They calculate that attempts at mating make up 11 percent, or 22 separate instances, of 186 interactions observed between octopuses over a total of 7.3 hours. They describe mating as not season-specific since the video records attempts in January, March, July, August and November, but not in February, April, June or October.

Reaching toward one another without touching emerges as the most common in 72 percent of 512 recorded actions.

Octopus body pattern display signals find rare incidences of physical contact, with grappling and touching generally predictable outcomes from two octopuses darkening to almost identical camouflages.

Interactions go from communication, through octopus body pattern display signals, to contact when one, then another octopus darkens and raises head and mantle over higher ground. They have fewer chances of resulting in fights between octopuses when the reaction is not darkening, extending arms or raising head and mantle over high ground. The interaction is going to lead into flight, not fight, when the second of octopus body pattern display signals results in a lightening of camouflage colors.

So darkness joins darkness before two octopuses swim into fights whereas lightness joins darkness before one swims away in flight.

Co-authors Peter Godfrey-Smith of City University of New York, Matthew Lawrence of Australia, and David Scheel of Alaska Pacific University know of similar darkening by fish.

They list the “dark face” that one common cuttlefish (Sepia officinalis) produces to communicate to a second a willingness to fight over food, mates or territory. The second common cuttlefish maintains an almost identical “dark face” if there is to be a fish fight and a far paler facial look if not. Co-authors Peter Godfrey-Smith as philosopher, Matthew Lawrence as diver and David Scheel as marine biologist note similar behaviors and color changes in algae octopuses (Abdopus aculeatus).

Twelve captive and 14 field studies of 12 other octopus species offers some, but not all of the same behaviors.

Crissy Huffard, senior research technician at California’s Monterey Bay Aquarium Research Institute in Moss Landing, provides similar results from investigations into octopus body pattern display signals.

She qualifies one octopus’s black-and-white striped patterns as “the signal, ‘I’m male’,” with corresponding or different colors and patterns channeling the other’s fighting or mating drives. She reveals: “Octopuses are probably not as completely asocial as originally assumed. Their communication system reflects the fact that they’re interacting on a fairly regular basis.”

The co-authors suggest that gloomy octopuses (Octopus tetricus) likewise use the body language of non-camouflaging behaviors and colors before agreeing or disagreeing to fight or mate. They think that octopus body pattern display signals can be witnessed wherever “a dozen octopuses or more” are gathered together.

Octopus flight (foreground) and fight (background) signals -- Octopus (foreground) displays pale color and extends one arm before withdrawing from approaching octopus (background). Approaching octopus displays dark color and stands tall, spreading its web and arms: David Scheel, usage restrictions: credit required, via EurekAlert!

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

octopus fight signals: David Scheel, usage restrictions: credit required, via EurekAlert! @ http://www.eurekalert.org/multimedia/pub/107172.php?from=316825

"Don't mess with the #octopus when it goes dark.": Current Biology @CurrentBiology via Twitter Jan. 28, 2016, @ https://twitter.com/CurrentBiology/status/692763762466648064

octopus flight signals: David Scheel, usage restrictions: credit required, via EurekAlert! @ http://www.eurekalert.org/multimedia/pub/107173.php?from=316825

For further information:

cellvideoabstracts. 28 January 2016. "Signal Use by Octopuses in Agonistic Interactions/ Curr. Biol., Jan. 28, 2016 (Vol. 26, Issue 3)." YouTube.
Available @ https://www.youtube.com/watch?v=5qNiPr8pYKU

Current Biology @CurrentBiology. 28 January 2016. "Don't mess with the #octopus when it goes dark." Twitter.
Available @ https://twitter.com/CurrentBiology/status/692763762466648064

Greenfieldboyce, Nell. 28 January 2016. “Shifting Colors of an Octopus May Hint at a Rich, Nasty Social Life.” National Public Radio > The Two-Way.
Available @ http://www.npr.org/sections/thetwo-way/2016/01/28/464447457/shifting-colors-of-an-octopus-may-hint-at-a-rich-nasty-social-life

“Octopus tetricus: Gloomy Octopus.” Busselton Jetty > Marine Research > Fish Finder > Local Invertebrates.
Available @ http://www.busseltonjetty.com.au/marine-research/fish-finder/local-invertebrates/gloomy-octopus/

Scheel, David; Peter Godfrey-Smith; and Matthew Lawrence. 28 January 2016. “Signal Use by Octopuses in Agonistic Interactions.” Current Biology 26: 1–6. DOI: http://dx.doi.org/10.1016/j.cub.2015.12.033
Available @ http://www.cell.com/current-biology/abstract/S0960-9822(15)01559-6