Fight or Flight Response in Mr. Crab

May 23, 2007 | No comments

Mr. Crab: “If I close my eyes then you don’t see me right!”

All animals that have made it this far on our planet have an innate reaction, one that instantly goes off even before a signal as to what to do reaches the brain, it’s called the “fight or flight” response.

Background

Last week I went up to Cape Tribulation (Australia) to get some camping done, admiring nature and swimming with the jellyfish/man-a-wars when the tide was high in the main bay. When it was low tide, remnants of ancient coral where exposed, long since dead but still as hard as iron. Walking along the exposed reef, I kept hearing a snapping sound all around me, I would then walk a little more, stop and again hear “snap, snap, snap”. Oddly enough, I never heard it “under me”, always a few meters AROUND me. This made no sense obviously, so I just crouched down until I could pinpoint one specific snap and followed it until I discovered what it was.

Fight, Flight or Hide

What I was experiencing on the ancient exposed reef was the reaction of thousands of little crabs, about the size of my fist that where incredibly well camouflaged - I can only guess it was either a mating call or a message to other that “this is my territory, stay out”. Their initial reaction to a HUGE 6ft tall, 160lbs white monster (I was wearing a bright white long sleeve t-shirt) was to stand absolutely still, not make a sound if I was within about a 3 meter radius from them, any further, they would either run off (flight) or cease all sounds/movement hoping I missed them.

Discovery: What to do?

Keep in mind, I had to spend several minutes to simply pinpoint one of these noble little creatures, they are incredibly difficult to find when they don’t move or make a sound - I saw only 5 of them during a 8 hour period, of which only one I was able to get close enough to take a picture. Their initial reaction once it became obvious I was ABOUT to find them was to run away like Armageddon was at their doorstep asking for their soul… they may be very small, but they can sure run/swim faster then I ever could.

Fighting me off

Below is a picture of a brave little crab trying to fight me off as best he/she could. This screams of bravery and this little guy should get a medal but alas, I was just playing with it, I don’t particularly like crab as food so I posed no danger to him. There where Dingos, birds and other marsupials along the beach when the reef was exposed and at night when it was high tide, who knows what lives in the ocean looking for a quick and easy snack. The ONLY way I could ever get a “fight” response from a crab was to corner it, otherwise, it was a futile effort of hide and seek with them having the upper hand. Keep in mind, these little guys are about 1/4 a pound soaking wet - they stand absolutely no chance against me even if I fought them with my eyes closed. Just think, what would your reaction be if a giant about the size of the Eiffel tower was trying to catch you and you get a small glimpse as to how they may have felt about me. Would you stand defiant against all odds, stand your ground and fight?

Also below is a picture I took as to the consequences that are very real to these little crabs on a daily basis, the cost of fighting to the death or hiding to the death. So as you can see, it’s totally logical that if you see a potential predator coming your way, running away is probably better then hiding or fighting them off. You can see this everyday in our own species and countless others.

Brave little soldier!