Friday Squid Blogging: Research into Squid Hearing


Squid can hear, scientists have confirmed. But they don’t detect the changes in pressure associated with sound waves, like we do. They have another, more primitive, technique for listening: They sense the motion generated by sound waves.


Squid have two sac-like organs called statocysts near the base of their brains. Hair cells line the sac and project into it, while a tiny grain of calcium carbonate, called a statolith, resides inside the sac. When the squid moves, the hair cells rub against the statolith, bending the hair cells inside the sac. This generates electrical signals that get sent to the animal’s brain telling the squid it has detected a sound.


Their results showed that squid can only listen in at low frequencies of up to 500 hertz. (By comparison, humans hear frequencies from about 20 to 20,000 hertz.) This means squid can probably detect wind, waves and reef sounds, but not the high-frequency sounds emitted by the dolphins and toothed whales that eat them, Mooney said.

Posted on February 18, 2011 at 4:17 PM17 Comments


Richard Steven Hack February 18, 2011 5:00 PM

“but not the high-frequency sounds emitted by the dolphins and toothed whales that eat them”

Sounds like an inadequate evolutionary adaptation then.

And why would a squid need to detect wind? Waves and reefs, yes, but wind?

jgreco February 18, 2011 5:08 PM

@Richard Steven Hack

Flying squid. I’m interesting in what exactly “reef sounds” are though, if not the sounds made by other animals.

Doug Coulter February 18, 2011 7:51 PM

Not having HF hearing might be an advantage. Think sonar and self beaching whales…we’ve made the seas so noisy that their long distance communication is effectively jammed. And unlike eyes, you can’t close your ears.

herring aid February 18, 2011 7:56 PM

This could explain why squid often tolerate schools of small fish in their vicinity. If the smaller fish depart quickly it alerts the squid to the presence of a larger predator associated with those higher frequency sounds. The smaller fish effectively serve as what marine biologists term a herring aid.

Moz February 20, 2011 2:11 PM


You might be right; Dolphins are thought to be able to use sound blasts from their sonar to stun fish. Maybe being sensitive to this would make things worse for the squid. If so it’s a pretty good example of how to stop your enemy adapting to your attack strategy.

Clive Robinson February 21, 2011 1:35 AM

OFF Topic.

Do the US wanabe cyber warriors spin faster than the centrefuges Stuxnet is alleged to have attacked?

US Deputy Defense Secretary William Lynn was at RSA and gave a talk that appears to be nothing but spin and hype verging on “think of the children” and “if you knew what I new” rhetoric.

Thus more likley aimed to raise money for the Pentagon, not anykind of security awareness in the industry…

He elaborated on the mainly discredited hypotheses of Stuxnet as an Al Qaeda weapon,

Why is it spin and rhetoric?

Well ask yourself why the likes of Stuxnet and other such worms and malware a discredited idea for an Al Qaeda weapon.

First off it does not fit in with what is currently known of Al Qaeda’s short term aims and objectives, or the long term aims of Osama bin Laden (get the US out of Saudi and possibly the rest of the Middle East).

Secondly, contary to what DDS Lynn alludes to with,

“As you know better than I, a couple dozen talented programmers wearing flip-flops and drinking Red Bull can do a lot of damage.”

Most industry experts think the “talented programmers” behind Stuxnet where far from “wearing flip-flops” and to have considerable expertise in amongst other things industrial control systems. Which is a niche area normaly populated by occasional beer drinking “engineers” with families not “Red Bull” drinking “MS Win nerds” without girlfriends.

That is the people with the knowledge and ability to attack the infrastructure via malware etc don’t fit the profile of either malware developers or terrorists.

But what of the broader implication of DDS Lynn’s “cyber attack by Al Qaeda” hypothesis to other terrorist organisations?

Does such an idea “hang together”?

The aims of most terrorist organisations is high impact “news worthy” attacks to get the fear element into a nations psyche.

To do that the public have to fear the weapons they use such as guns and bombs. What sort of “cyber weapon” achieves that fear?

Stuxnet has been the best example put forward so far, go ask your neighbour “Hey what about Stuxnet?” they are most likley to give you a blank look, and think your talking about some new kind of “fly trap” than a “terrorist weapon that is going to bring the sky down on them”. Ask them about guns bombs and WMD and they are almost certainly going to have an opinion.

That is currently “cyber weapons” don’t even make a blip on the public awareness, let alone with any terrorist angle so how is it going to get the national psyche…

That’s not to say at some time in the future the public view point will not change, but I think that an awful lot of non crime cyber damage that impacts their lives will have to be done first.

And this is the crux of the matter, cyber crime will do considerably more damage more quickly than cyber terrorism. And thus the cyber defences will rise to meet crime and quickly out strip the abilities of terrorists.

Thus the terrorists will have to not just “buy in” technology from the cyber criminals, they will also have to find viable cyber targets that will effect the national psyche.

What are the odds of a terrorist organisation doing this compared to bombing a shopping center or transport hub?

Will terrorist get around to using malware? Yes I think they will but for conventional criminal gain (ie money) to support their organisation not to grab a nations psyche.

Tim February 21, 2011 4:15 AM

Clive, it’s my opinion that cyber terrorism will only become more prevalent than conventional terrosism when it is easier to carry out than that, it has similarly visible results to unite the masses behind, and perhaps most importantly it is easier to confirm who carried it out.

Meanwhile money-making will be it’s key focus, however they will also seek to gain from the sale of technology – see this link
– much in the way that aQ apparently sold to China unexploded cruise missiles from the 1998 attack on their Afghan training camp and used the money to fund future more notorious attacks.

Meanwhile, back on topic with the squid’s hearing range, it’s exciting to consider they have already evolved the ability to not hear Justin Bieber. I wish I couldn’t hear her either…

mw February 21, 2011 9:42 AM

Mooney, et al, suggest that squid may use near-shore and near-surface sounds, and the interactions of large wavelengths with undersea physical structures, as navigational cues that help squid determine their habitat.

Perhaps, squid also use their auditory ability as an alternative physiological temperature detection mechanism. If, as Mooney’s study suggests (based on a two-squid sample), squid cannot hear at temperatures below 8 degrees centigrade, then when a squid cannot hear any sounds, it may conclude that it is in water colder than 8 degrees centigrade.

According to a NOAA memorandum (NMFS-NE-193) “Longfin Inshore Squid, Loligo pealeii, Life History and Habitat Characteristics” Longfin inshore squid are generally found at water temperatures of at least 9 degrees centigrade and make seasonal migrations that appear to be related to bottom water temperatures.

So, it may be that squid are using their auditory ability to sense temperature – at least to detect when it’s colder than 8 or 9 degrees centigrade.

However, if squid can determine temperature using other biological senses, it may be problematic to test whether squid also use their auditory ability to detect temperature.

trintakilos February 21, 2011 10:32 AM

Well. Since this is my first posting I would like to mentally spit my contextual security schneider blog commenting system awareness type of feeling. Statistically .’terrorism’ may at the last seem to be a fabricated word made by ‘Advanced democratic societies’ as a control mechanism. I Think we are falling on a brainwashed linear regression for fear. And I see so many ‘terrorism’ thinking links as a sight of this type of evidence. Notice how many times commenting logic deviates to this matter. So excusé mói but you need to get your Unicode straight and get the big picture. When so many of you fight for the misspelling of social-media-whore fabricated word ‘Hacker’ you fall in the same terrain when sticking out argument’s logo typed by ‘terrorism’. Bare me with your self-induced cultural poisons.

Broggly February 23, 2011 12:59 PM

@Richard Steven Hack

One thing you have to remember is that evolution works with what it has. For example, because of the anatomy of our fish ancestors the rucurrent laryngeal nerve goes into the chest and loops around the aorta before turning and heading back up the neck to innervate the voicebox. It’s probable that cephalopods were stuck with that kind of ear long before dolphins and whales evolved.

Clive Robinson February 23, 2011 5:26 PM

OFF Topic.

To be presented at a forthcoming Usenix Confrance (), the following paper is a “must read” for all those who have to deal with security and flash media such as SSD’s etc,

Put simply SSD’s can replace conventional hard drives except that “secure erase” functions don’t work and can leave more than 50% of a “securely deleted” file not deleted…
those thk

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