It had to by flying squid today, because of this story in Nature about squid locomotor energetics. Scientists measured the velocities of flying squid in air, and noted that they can move five times faster in a less dense/viscous medium (as we say in our technical discussions of this issue…no duh.) So they are proposing that maybe these species of squid do it to travel long distances efficiently.
Querulous voices were raised to point out something equally obvious: then where are they all? Photos of squid in flight are extraordinarily rare — they don’t do it routinely, it seems. It’s more probably an escape behavior only used when predators are attacking.
I’m going to side with the nay-sayers. The observation that squid move through air much faster than they do through water is utterly trivial; the real problem with the interpretation that it is a common locomotor behavior is that it sure doesn’t seem to be all that common. Show me lots of movies of squid schools leaping in a prolonged series and maybe I’ll change my mind.
(Also on Sb)
The non-trivial part is the calculations that suggest that flying squid cover distance more efficiently, energetically, than they would by swimming.
As for the rarity of direct observation, maybe they’re primarily nocturnal. Maybe pelagic squid are unlikely to behave routinely when there’s a boat full of human observers in the vicinity.
No survivors.
Holy crap, that’s beautiful.
Also kind of freaky. If these things develop lungs and tools, the human race is boned; they would dominate the sea, land, and air.
Well, this one, not so much. :)
Come to think of it, they are capable of cloaking…
Both in the camoflage sense and being cloaks themselves.
Random link brought to you by the hognose snake:
Article: Cracked – 8 Ingenious Ways Animals Outsmart Predators
er camouflage
No doubt they’ll be using it to poop on annoying primates who are encroaching on marine territory.
Glen Davidson
regardless of how rare this behavior may be, it certainly could explain how the pacific arboreal octupus got into its habitat.
They’ve already got jet propulsion. Wait until they evolve turbojet propulsion. Then we’re really screwed.
Seriously, incredibly beautiful. And as one who’s tried for HOURS to get a good photo of a flying fish in flight, I’m envious.
When we sailed across the Pacific Ocean in 2010 we frequently found squid all over the deck in the mornings. This never happened during the day. I suspect the squid come near to the surface during the night and some mechanism brings them onto the boat. I always suspected it was wave action but that never explained some of the places we found squid. An airborne flight reflex is a better explanation for why we found them where we did.
WHEEEEEEEEEE!!
The complexity and limitless beauty of our world continues to astonish and delight me. This photo moves me, as I am similarly moved by watching the birds at my feeders on this snowy morning in New England. I think what moves me is that all life is on the edge – and especially for so many creatures in the wild, one minute may bring prosperity and the next, death. Every moment of life, here and now, is amazing. And when that little scrap of life is embodied in what appears (to human eyes) as “beautiful,” well, it’s moving.
—
That is all – back to lurking, and back to Real Life(TM), which despite its beauties and amazingness, continues to confound and entangle me.
One of the things that struck me when reading “Kon Tiki” nearly 60 years ago when I was a kid was Heyerdahl’s report of finding small squids on top of the raft’s hut in the morning, and then finally seeing the small squids zooming onto the raft.
Humans primarily move around through a practice known as parkour because it enables quicker travel around buildings, dumpsters and other natural objects.
Notice the difficulty they have in the relatively simple act of perching.
Best. Squid. Ever.
A lot of this energetics has already been worked out for ‘porpoising’ in odontocetes (surprise!) and penguins. That’s if I remember my 3rd yr biomechanics class about 20 years ago. They’ve studied it in sports, too, and in engineering. Turns out you can swim faster a bit deeper (away from the surface), and you can travel well through the air, but at the surface there are significant costs (surface tension among them). So if you’re a fish and you wanna go fast, stay away from the surface; if you’re an air breather and you wanna go fast, jump clear of the water rather than moving at the surface. Predation avoidance can pick up the pieces of whatever is left.
Examples: backstroke racers begin by ‘dolphin-kicking’ near the pool’s bottom; boats with hydrofoils to reduce surface area of the hull experiencing drag in the water.
I am really suspicous of this claim. Though it is true that the force of resistance caused by a medium increases with density, what matters is the overall net force. I’m not certain how squid generate propulsion, but I can almost garuntee that the force of propulsion is near 0 in air. So the fact that the air resistance is less is essentially meaningless. It may be true that shooting into th air saves energy, as the time spent in the air is effortless forward motion, I see no way for them to move at a greater velocity.
If PZ were to spend a few tens of hours annually buzzing about shoal but squiddy waters in a zodiac, upside the head smackings by the creatures would soon persuade him that they are second but to flying fish in this distracting behavior.
The state of knowledge as I learned it: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=4391220
When it was revisited: http://icb.oxfordjournals.org/content/42/5/1071.full
And perhaps more recently:
http://www.is.kanagawa-u.ac.jp/study/staff/sugimoto/Sugimoto_HP/Sugimoto_NCTAM57.pdf
I’m sure it requires a big burst of energy to propel them out of the water, so it doesn’t seem like an efficient mode of motion.
Maybe they’re showing off for the ladies.
In order for their speed to increase fivefold in the air they would need to accelerate sharply once they left the water. How do they manage to do that?
I find comments like this most puzzling. If you already know that you don’t know what you’re talking about, then what is the point of taking a whack at it anyhow? And why would you want to do so publicly?
just as wrong as your spelling.
It’s jet propulsion. By shooting a thin jet of water from their mantle cavity through a narrow siphon, they are moved in the opposite direction. The force is the same in air or water, but the resistance is much lower in air. Applying a constant force through the water-air transition results in automatic acceleration (PZ’s right; that part’s trivial). The specialized fins and tentacles turn enough forward motion into lift to keep them in the low-resistance environment for a while, and extra squirts while in air can generate even more lift. You can see this clearly in this photo.
The calculations evidently suggest that the extra efficiency (covering greater distance faster for a given effort) more than makes up for the extra energy required to break surface tension.
It’s totally plausible. Too bad this is all based on an unpublished conference abstract so we can’t check the math.
oops, forgot: Note that the abstracts linked by slatham all predict that porpoising is more efficient than swimming above a certain crossover velocity.
a) these squid are the fastest-swimming invertebrates that exist.
b) as noted above, they are not passively porpoising (like, you know, porpoises, or penguins) or even just gliding (like a flying fish*): they can actively fly for short distances, generating forward motion, and therefore lift, actively when in air.
*flying fish can keep just their tails in the water and generate forward motion/lift that way for a while. But mostly they don’t.
Looks like something outta a scifi show. but cool, lets’ do an aerodynamic test on it :-)
Flaunting one’s ignorance increases credibility. Have you learned nothing from the Republican debates?
Do squids brains have pleasure centers? maybe it just jumps into the air because doing so provides pleasant sensations? I am obviously not well up in biology enough to know, so I ask.
Ah, a new hypothesis. Maybe that is not water being squirted out while in the air.
I believe this hypothesis was first stated by naturalcynic at #11. And quite succinctly, too.
the original article really relates back to “porpoising” behavior noted for many marine living species, mammals and fish included, as I note some others have posted some links to as well.
I’ve perused the lit on this subject over the years, and there is no satisfactory (to me) test of this behavior that I have ever seen that really supports the idea of porpoising behavior occurring because it is energetically more efficient.
what is lacking:
-nobody has really done direct energy studies, mostly because the species involved are not exactly easy to study in this fashion, since they typically refuse to do these behaviors in captive situations, so everyone relies on plausible, if potentially inaccurate, models.
-nobody has resolved why it is, that if this behavior maximizes efficiency, it observed so erratically in the species that actually exhibit it.
for example, in marine mammals that exhibit the behavior, sometimes you will see a regular pattern, sometimes not. If it really is an issue of efficiency only, you would indeed expect selection to really narrow the range of patterns exhibited.
Some have tried to explain this through much more complicated models:
http://www.jstor.org/pss/3884627
but that’s all these really are, models, and the fact remains that we don’t see exactly the same patterns as would be predicted from an efficiency model when we look across different populations, even of the same species.
I would note than in the much more well studied exocoetids (flying fish), the general consensus is a rejection of energy efficiency related hypotheses:
http://www.springerlink.com/content/khk627264325j4r6/
so, circling back round, essentially PZ is correct; if this was truly an energy efficiency only behavior, it would not only be much more common in squid, but in ALL near-surface marine species that migrate distances to harvest patchy resources.
I remain unconvinced that energy efficiency is a primary reason for this behavior.
Porpoising is a red herring; this behavior is completely different.