Cephalopods have a slew of defense mechanisms to detect, evade, confuse, and deter predators. It only makes sense that they would need multiple defenses being one of the squishiest and protein-rich species in the ocean. No tough skin to bite through and no hard shell to crack open. Obviously, octopuses don’t want to end up as dinner. So, to help avoid this fate, they use expert camouflage, release clouds of ink, make quick escapes, and all sorts of other forms of trickery! One such trickster behavior is known as protean behavior. Read on to find out all about it!
What Is Protean Behavior?
Protean behavior is when an animal acts unpredictably to prevent a predator from anticipating its future position or actions.
On land, animals frequently flee in an irregular manner, like a rabbit running away in a zig-zagging pattern. Some animals, like butterflies, go the extra mile and incorporate protean behavior into their day-to-day routine resulting in a loopy, spinney, and overall spathic flying pattern.
If you’ve ever chased a cockroach around your house as you try and kill it, you have witnessed protean behavior in action! You never know which way that bug is going to go.
Can Humans Show Protean Behavior?
As humans, we also exhibit protean behavior, sometimes intentionally or unintentionally.
Someone suddenly breaking down crying or flying into a rage usually makes the people around them feel a bit off-kilter and could change how they were treating you. Military strategists, sports coaches, and game theorists all partake in well thought out protean behavior.
How to stop the enemy, rival team, or match opponent from predicting and preparing their next move? Randomness!
Underwater, this kind of unpredictable behavior has been observed in Yellow-Spotted Pufferfish (Torquigener flavimaculosus) who exhibit erratic zigzag swimming when trying to evade predation.
🐙 Octopus Fun Fact
Cephalopod behavior has been studied since the 1950s; however, researchers only recently started looking into their protean behaviors.
Why Is It Called ‘Protean’ Behavior?
Back in 1970, Humphries and Driver were the first to research and publish about adaptively unpredictable behavior. They coined the term protean behavior after the mythical Greek river-god Proteus, a.k.a. Old Man of the Sea, who was able to change shape and form.
He was the old shepherd of Poseidon’s sea creatures who possessed the gift of prophecy but refused to share what he knew with anyone. He would change his shape to escape anyone wanting information from him.
The only way to get an answer was to catch him during his midday nap and then hold onto him while he attempted to shapeshift till he eventually revealed what he knew.
Which Escape Trick To Choose? Cephalopods Have A Bunch Of Them!
An octopus’s first line of defense is avoiding being seen at all, which they are particularly good at! They spend ample time in their dens, and when they come out, they can match their surroundings in a split second.
If this first line of defense fails, it’s time to activate their arsenal of secondary defenses! This is where deimatic behavior (startling actions to make a predator hesitate), aposematic behavior (warning coloration displays), and ultimately protean behavior come into play.
After all, there comes the moment of truth to decide whether to fight back or flee.
Types Of Protean Behaviors Octopuses Display
Researchers have described protean behavior as behavioral anarchy (I do what I want to when I want to, and you won’t know what’s happening.)!
Protean behavior can come in many forms to confuse their predators:
- “Blanch-ink-jet” maneuver
- Rapid changes in appearance, like pattern flashing or deflective marks
- Unpredictable speeds (slowing down, going fast), like erratic jetting
- Releasing clouds of ink
🐙 Octopus Fun Fact
When threatened, octopus and cuttlefish can use their fast-acting chromatophores to produce color convulsions. A predator expects to see one thing but then gets thrown off when multiple images are flashed in its face.
Cuttlefish can make such wild and quick color displays on their bodies that scientists hypothesize that they are able to hypnotize prey items.
The Constant Biological Arms Race Between Predators and Prey
Why go through all this trouble? Why would an animal need to have so many tricks up its sleeve? Because predators evolve to track and predict the movements of their prey!
If a prey does something unexpected, predators will have a harder time catching them.
Let’s say you’re a flounder and you get the hankering for a Longfin Squid. As the flounder, who’s been chasing around squid for a while now, you know a Longfin Squid will try and escape backward via jet propulsion.
The squid also knows you know this.
So, instead of just scooting away, it blasts out a cloud of ink. The flounder is then like wait, woah… what is this? What am I looking at? Is the squid in the ink? Is the ink the squid?
And there you have it folks: unpredictability and a successful squid escape!
Using Ink Plumes To Escape
A study looking at different predator reactions on a Longfin Squid found ink plumes to be a handy protean behavior! Discovered by science!
Ink caused flounders to misdirect their attacks 51% of the time to the ink cloud rather than the squid. NOT TODAY FLOUNDER!
🐙 Octopus Fun Fact
Inking as a defense can also be categorized as deimatic behavior since it additionally startles predators. Both behaviors are meant to confuse and disorient their predator and slow their reaction time. These behaviors are still considered secondary defense tactics since fleeing had the best overall survival rate for the squid.
Interestingly, squid varied their tactics depending on which predator it encountered!
3 vs 1: Who’s Coming Out On Top?
In a related study, cuttlefish were pitted against Bluefish, Summer Flounder, and Black Seabass. These crafty cuttlefish showed 3 primary and 15 secondary defense behaviors. This clearly shows that cephalopods have the intelligence to determine which mix of defenses would work best on different types of predators.
Pretty incredible for an animal without a backbone! Even hatchling cuttlefish who had never encountered a predator were able to pull out their bag of defensive tricks!
Protean Behavior: So Many Tricks, So Little Time!
Essentially, the more ways you have to escape a predator, the higher chance you will live to see another day. Complex, unpredictable escape maneuvers are the name of the survival game when you’re a cephalopod.
If you want to educate yourself some more about all sorts of different cephalopods, take a look at our encyclopedia. Or, what we call it, our Octopedia!
Connect with other octopus lovers via the OctoNation Facebook group, OctopusFanClub.com! Make sure to follow us on Facebook and Instagram to keep up to date with the conservation, education, and ongoing research of cephalopods.
More Posts To Read:
- Meet the Cockeyed Squid: the Deep-Sea Animal with a Giant Eye!
- ‘Cephalotography’ Of The Week: Jialing Cai
- 10 Facts About Baby Nautilus!
- Book Giveaway: The Lives of Octopuses and Their Relatives
- Do Octopus Bite?
Corinne is a biologist with 10 years of experience in the fields of marine and wildlife biology. She has a Master’s degree in marine science from the University of Auckland and throughout her career has worked on multiple international marine conservation projects as an environmental consultant. She is an avid scuba diver, underwater photographer, and loves to share random facts about sea creatures with anyone who will listen. Based in Japan, Corinne currently works in medical research and scientific freelance writing!