I just put up a new widget on the right side of this page. The network is participating in the Science Bloggers for Students Project, a month-long charity drive facilitated by the good folks over at www.donorschoose.org. If you click on over to our donorschoose.org page, you’ll find a whole slew of projects that we’ve selected to campaign for. The way donorschoose.org works is simple – teachers of needy classrooms post project descriptions, asking for donations to help them accomplish specific goals in their classrooms, which are often in very high-poverty areas. Donors can then choose which projects they want to support. Each project has a cost breakdown and description written by the teacher. Overall, it’s a very efficient charity (about 92% of what they bring in goes directly to funding projects, which is pretty much as efficient as large non-profit organizations get.) So head on over the The Gam Classroom Initiative page, check out the projects, and give whatever you can! Take this opportunity to help give these kids the science education they deserve.

I’ve decided to try to resurrect the blog carnival Encephalon. Once upon a time, any internet user with a thirst for good neuroscience-related blogging could pop on over to an edition of this carnival and drink their fill. Unfortunately, it’s recently been on hiatus, and I missed it so much I had to try to bring it back to life. It’s got a spiffy new page, and hopefully many more editions to go!

The basics: It’ll run once each month, on or around the last Saturday of the month. Any and all blogging on neuroscience and/or psychology is fair game, including (for example) comparative, social, clinical, and biological psychology, neuroethology, computationational, cognitive, social, and molecular neuroscience, etc. I’ll host the first edition at the end of October, to get things started; you can email your submissions to me at mike.lisieski(at)gmail(dot)com .

I’m looking for hosts, so drop me a line via email or twitter (@Cephalover) if you’d like to host an edition.

Thanks for reading!

As I promised in the title, here are some baby octopodes (Octopus rubescens, the east Pacific red octopus, to be exact.) These guys are so small that you can see the individual chromatophores on them (the reddish spots)!

For comparison, here’s a photograph of an adult O. rubescens, graciously provided to the world by Taollan82:

Those little buggers have quite a bit of growing to do!

Moving on: “Sharktopus”, the long-awaited film about a Navy-engineered half-shark half-octopus monster, airs tonight on Syfy. Not having a TV, I won’t be watching, but it looks pretty incredible. Check out the trailer:

Two things I noticed: first, whoever performed that theme song deserves lots of credit – it makes the preview. Secondly, Sharktopus seems to have an appetite for skinny women in bikinis. You’d think that, being a presumably efficient predator, it would be attracted to prey with more body fat (eg. prey that would yield a higher calorie intake to expenditure ratio,) and it seems like there’s no danger that a large person could hurt it – but it still almost exclusively goes after skinny beach babes. How could the producers fail to consider the probable features of Sharktopus’s energetics? They must not be biology geeks.

Thanks for reading!

Cephalopods are great subjects for studies on vision, because they are so dependent on their vision that you can get robust behavioral effects by manipulating the visual environment of a test animal. In some new research in the October edition of the Journal of Experimental Biology, CM Talbot and J Marshall (from Queensland) investigate the visual system of the pyjama squid (S. lineolata) and two species of cuttlefish (S. plangon and S. mestrus) – specifically, to find out whether they can respond to polarized light, and in the case of S. lineolata, how photoreceptors are distributed on its retina. I’ve blogged about a study on visual perception in Nautilus before, as well as a study on the retinal topography of squid, so if you would like to see more of the same sort of research, check out those posts.

In these two papers, the authors assessed the ability of their experimental specimens to respond to polarized light by monitoring their optokinetic and optomotor responses to a rotating drum. The optokinetic response is the movement of an animals eyeballs to follow a moving object in the visual environment, while the optomotor response is the movement of the animal’s body to follow movement in the visual environment. The experimenters monitored the optokinetic response in S. lineolata, because it tends to stay motionless on the substrate, partially buried – as such, it will not exhibit an optomotor response under most circumstances. On the other hand, S. plangon and S. mestus both tend to hover in the water, and so show optomotor responses more readily.

A basic scheme of the apparatus used is shown in this figure from the S. lineolata paper:

The animal is in the tank (in this case, prevented from burying itself by being enclosing in a transparent cylinder,) while a drum is rotated around the tank. By varying the pattern on the drum, it is possible to determine the sensory abilities of the animal – assuming that animals generally don’t inhibit optokinetic or optomotor responses, the animal will respond to any pattern it can perceive. If the animal can’t perceive the pattern on the drum (for example, if the drum is visually continuous, as is the case with an all white drum,) it will not perceive any motion and the response will be absent.

The authors used a drum that consisted of alternating stripes of orthogonally oriented polarization filters – that is, the drums were striped, but the difference between adjacent stripes was only in the direction of polarized light that they transmitted. All the stripes transmitted the same total amount of light, and had the same appearance. Thus, the animals would only show an optomotor or optokinetic response to these drums if they could perceive the direction of polarization of the light.

In fact, this is what happened, in all three species. Two control drums were used, one of alternating black and white stripes (to make sure the animals had otherwise normal optokinetic and optomotor responses) and one of a uniform-direction polarization filter (to make sure that the animals weren’t responding to some other part of the drum – the tape used to hold it together, seams resulting from the drum’s construction, etc.,) making it pretty clear that the animals were responding to the alternating directions of polarization and not anything else.

This result is pretty unambiguous, but I’d like to point out a problem that this type of experiment presents in its interpretation: specifically, it’s very difficult to interpret negative results. In this case, it’s very easy to know what it means in terms of the animal’s sensory ability when it responds to a stimulus: it means the animal can detect that stimulus. But what if the cuttlefish didn’t respond (for example, as was found in a very similar study by Darmaillacq and Shashar (2008) in a different species of cuttlefish, Sepia elongata)? It’s hard to know what that means – did the animal fail to perceive the stimulus, or did the stimulus just not mean enough to generate a behavioral response? This is a general problem that crops up in studies on sensation and perception in animals, or any study that relies on an animal perceiving something and emitting a behavioral response. Many things need to happen to get any behavioral response to a stimulus, even one as apparently simple as eye movements. The animal must have a functional sensory apparatus appropriate to perceive the stimulus, it must have the energy and intact musculature to perform whatever behavior it is you’re looking for, it must be expressing no other behaviors that might mask or supress the behavior of interest, it must be motivated to perform the behavior of interest, etc. A negative result in such an experiment means that one of these many things is not the case, but because it’s so difficult to tell the difference between all of these steps between “stimulus” and “behavior”, it’s hard to say what exactly it is that the animal isn’t doing. Is it failing to sense the stimulus, is it failing to respond because the stimulus isn’t relevant, or is it failing to behave because it’s afraid, or stressed, or tired? Darmaillacq and Shashar note that S. elongata has retinal anatomy that looks like it would allow the animal to sense polarized light, and so they are (wisely) wary of claiming that their subjects could not perceive polarized light – but there’s no way to make any claim about S. elongata‘s vision at all from these results (except, of course, the most conservative assertion that S. elongata failed to show an optomotor response to a certain type of polarized-light stimulus under the experimental conditions used in that specific study.)

Fortunately, though, Talbot and Marshall found positive results, and so avoided that quagmire all together. It turns out that all three species they studied can respond to polarized-light stimuli with optokinetic or optomotor responses. They went on to examine the distribution of photoreceptor cells (also called “retinal topography”) in the S. lineolata retina. If you’ll remember from my post on squid visual ecology, it turns out that you can relate the retinal topography of cephalopods to their lifestyle – squids that live near coasts have retinas that are specialized to allow the animal to see below it clearly, whereas oceanic squids have retinas that are specialized for monitoring the water column above them. What might we expect from S. lineolata, an animal who spends much of its time buried in sand? The sensible answer is that is eyes would be specified to look up, since that’s where its predators and prey would be in most cases. Let’s take a look at what Talbot and Marshall found:

The darker the blue is, the higher photoreceptor density is in that area. It turns out that the striped pyjama squid does indeed have a high photoreceptor density in the ventral part of its retina, which probably gives it good visual acuity in the upper part of its visual field (if you don’t know why this is, check out this explanation of image formation in the eye for a primer.) This fits in neatly with what we know about the lifestyle of this squid.

I hope these studies represent the start of a trend towards the study of less “classical” cephalopod species (the “classical” ones being Loligo pealai, Octopus vulgaris, Sepia officinalis.) There’s a lot to learn from the less common species of cephalopods, due in part to the fact they we know very little about most of them.

Thanks for reading!

Talbot CM, & Marshall J (2010). Polarization sensitivity and retinal topography of the striped pyjama squid (Sepioloidea lineolata – Quoy/Gaimard 1832). The Journal of experimental biology, 213 (Pt 19), 3371-7 PMID: 20833931

Talbot CM, & Marshall J (2010). Polarization sensitivity in two species of cuttlefish – Sepia plangon (Gray 1849) and Sepia mestus (Gray 1849) – demonstrated with polarized optomotor stimuli. The Journal of experimental biology, 213 (Pt 19), 3364-70 PMID: 20833930

I have three exams next week, so I won’t have another substantive post up until Thursday-ish, at least. In the mean time, enjoy this (under-viewed – only 600 views in 2 years!) video of some captive-bred baby cuttlefish munching on some copepods:

The videographer, as far as I can tell, is a physicist from the Netherlands who does work on medical imaging (and films cuttlefish, apparently.) Neat!

Everybody likes cuttlefish, it seems. They’re neat-looking, sociable, and display lots of entertaining behavior. I think it’s about time, then, to start talking about what cuttlefish do best: change color! I’ll start at what is, as far as I can tell, the beginning.

In 1988, Roger Hanlon and John Messenger published a paper called “Adaptive Coloration in Young Cuttlefish (Sepia Officinalis L.): The Morphology and Development of Body Patterns and Their Relation to Behaviour.” This paper lays out a description of the body-patterning behavior of young cuttlefish (S. officinalis), paving the way for many future studies on this behavior and the environmental features mediating it. The authors hatched and raised “more than 50″ cuttlefish, recording their behavior while they were in the laboratory, and then releasing them into the sea and videotaping them. From this (very large) set of data, they developed a systematic description of the various components of cuttlefish body patterns, as well as some ideas about what adaptive function they serve to the cuttlefish to use them. In addition, they did some microscopic analyses of the animal’s brains and skins, which I will spend less time on here.

The authors decided, based on precident as well as their own ingenuity, to describe the body patterns of cuttlefish (that is, the patterns of postures and colors that cuttlefish display) using a hierarchical scheme. In this scheme, each body pattern corresponds to one or a few behaviors, during which it is expressed. The body pattern is itself composed of multiple components – it has chromatic components (specific patterns of coloration,) textural components (specific patterns of skin texture,) postural components ( specific ways the cuttlefish holds its body,) and locomotor components (the ways the cuttlefish moves its body during the display.) Each of these components is made up of several units. The term “unit” as used here refers to a group of muscles that acts together to produce a local effect, many of which add up to become a body pattern component. For example, the group of muscles in each arm that hold that arm in a certain position make up a postural unit, and all of the postural units (that is, all of the arm and mantle muscle groups) together make up a postural body pattern component. Each unit is in turn made up of a number of elements, which are the smallest possible pieces that can display a particular tiny piece of a body pattern – for example, a single arm or skin muscle, or a single chromatophore. If that confused you, just take a look at their first figure, diagramming this concept:

Click through for a larger version.

The authors identify 54 components in all: 34 chromatic components, 6 textural components, 8 postural components, and 6 locomotor components. They also identify 13 distinct body patterns that are made out of these components: 6 chronic patterns (those expressed stably for a long time) and 7 acute patterns (those expressed transiently, usually in reaction to some significant or disturbing event.)

As an aside, I’d like take a moment to throw around a few counter-arguments to a common abuse of this line of research – namely, the claim that people like to throw around that cuttlefish and squid have a “language” that they express with their skin.

Firstly, cuttlefish displays are not symbolic – a cuttlefish who displays (for example) a pattern associated with mating is symoblizing sex, or the desire to have sex – the fact is that cuttlefish that want to have sex behave in a particular way. Calling this language is like saying that your dog is speaking to you when he humps your leg. He’s not telling you that he wants to have sex – he’s just doing what amorous dogs do.

Secondly, cuttlefish displays do not seem to have syntax. One of the things that makes language useful, and indeed defines language, is the ability to use various components of that language in novel ways, to communicate novel ideas. Related to this is the fact that the meanings of symbols are arbitrary – they can change, and do not neccessarily resemble or otherwise relate to whatever is being symbolized. There is simply no evidence that cuttlefish body patterns are this flexible, or ever mean anything besides making the behaviors they are part of more distinctive or effective. They may serve as an avenue of communication between conspecifics in some instances (in fact, they almost certainly do) but it is woefully inaccurate to describe them as language, especially without any further qualification.

Even if cuttlefish body patterning were a language, it would be a poor one. In most languages, a small number of symbols are used in various combinations to make a variety of units of meaning. For example, letters combine to form words, which combine to form short phrases. In english, there are 26 letters and many thousands of words and short phrases. Combining letters generates new information, not contained in the individual letters. The transition from components to body patterns in cuttlefish, on the other hand, causes information to be lost. Out of many components, cuttlefish put together only a few units of meaning.

So dear internet: I know how much you love cuttlefish, and I know that you want everybody else to love them, too. Exaggerating the evidence to make them seem more “intelligent” is not a valid way to do this, and makes you look unintelligent, dishonest, or both. Please, for your own good and the good of cephalopods everywhere, stop.

Anyways, back to the paper:

What do cuttlefish use these body patterns for? Most of the chronic body patterns are used for crypsis, or camoflage. A cuttlefish will use these patterns to blend into whatever is around them, so that they don’t get eaten. The plate below shows three cuttlefish in different developmental stages blending into the same substrate. The youngest one (towards the bottom of the photograph) is showing (as well as I can tell) a “strong disruptive” pattern, made up of highly contrasting dark and light components. The next oldest one (towards the top of the photograph) is showing a “weak disruptive” pattern, with the same basic scheme but with less contrast. The oldest one (right in the middle) is showing a “dark mottle” pattern, which is just what it sounds like:

When hiding fails, cuttlefish will show a variety of acute patterns in defense. Included among these are “uniform blanching” and “uniform darkening”, both of which are used to confuse would predators. A posture called “flamboyant”, where the cuttlefish waves its arms in the water, is used to startle predators. Adult cuttlefish use a pattern called the “deimatic” pattern, where the cuttlefish flattens and turns completely white except for a few dark markings on the mantle is theorized to be a sort of bluff: it makes the cuttlefish look bigger, and (hopefully) frightenes whatever predator is pursuing the cuttlefish enough to drive it off.

Patterns called “zebra” and “intense zebra” are used in social behavior, which primarily consists of sexual behavior and agonistic behavior (fighting or aggressive displays.) Variations on these patterns are used to distinguish between males and females. The picture below shows a male displaying the “intense zebra” pattern to a female. The authors note the critical inclusion of the extended and densely patterned fourth arm (the one most towards the bottom of the photograph,) the absence of which is one of the things that distinguishes the female “zebra” display from the male “zebra” display.

Click through for a larger version.

Finally, (and this is what I like best about this paper,) the authors close with a call for work “towards a comparative cephalopod ethology.” I can’t say it any better than they did:

It is clear from our work and [others] that cephalopod body patterns are inextricably linked with cephalopod behaviour so that study of body patterns becomes central to cephalopod ethology…

Recently there has been increased interest in ecological studies of cephalopods and we hope field researchers will begin to record systematically ethological data such as adaptive coloration, with the long-term goal of providing a more comprehensive view of their behaviour and life style.

Thanks for reading! I only covered this paper in the roughest way, so I urge those who want to know more to check it out – it’s available from Royal Society Publishing.

Hanlon, R., & Messenger, J. (1988). Adaptive Coloration in Young Cuttlefish (Sepia Officinalis L.): The Morphology and Development of Body Patterns and Their Relation to Behaviour Philosophical Transactions of the Royal Society B: Biological Sciences, 320 (1200), 437-487 DOI: 10.1098/rstb.1988.0087

To hold over all of you cephalophiles until I can finish the upcoming post on the study of cuttlefish body patterns (it will be good, I promise) here’s a selection of some of the best recent cephalopod-related videos posted to Youtube:

First, the Flapjack Octopus, O. californiana. This is benthic (ocean-bottom dwelling) species of octopus found off of Japan and California (and I suspect, other places in the Pacific, even though it’s only been found off of those coasts.) It’s also probably the most awkward-looking cephalopod in existence.

Let’s take a look at some cuttlefish! This first one shows some great slow-motion footage of a cuttlefish feeding on crustaceans (well, he misses one, but gets the other.)

Here’s a very young cuttlefish (probably S. bandensis) taking a walk around its tank. In case you’re wondering, yes, it is as cute as it sounds.

Here’s the same cuttlefish (I think), a bit older, and hanging out with some coral polyps. It looks like it’s mimicking the movement of the polyps with its tentacles.

Finally, we see the cute little guy (I think it’s the same one, but I could be wrong) “begging”, a behavior that is (anecdotally) reported in many cuttlefish kept in tanks, and is folk-theorized to be related to the cuttlefish learning that people bring them food.

Thanks for reading!

Here at the Southern Fried Science Network, all of us bloggers have been charged to post articles dealing with ocean-related pseudoscience as part of SFSN’s first “Ocean of Pseudoscience Week.” Since I try to keep this blog firmly focused on cephalopods, I was at first antsy that I would not find anything to write about. However, the (sometimes distressingly) wide pool of information that is the internet has not disappointed me.

You’ve all heard about Paul the Octopus by now. A Google search for “Paul the Octopus” (the exact phrase) turns up 5.5 million results. A blossoming cephalopod enthusiast who is curious about Paul can pick from literally millions of sources of information to hear about this phenomenon, and if she’s smart, will try to pick one that seems credible. Like, say, a CNN news report. She would find some informative and entertaining quips, and would mostly get the facts straight. That is, until she got to the point in the article where the CNN reporter asks an “expert” the critical question:

“Can an octopus really be psychic?”

After reading this section, if she had any sort of head on her shoulders, our inquisitive internet reader would (hopefully) be aghast, and a bit miffed that a CNN report would be such a lousy source of information.

Before I go on, let me say that there are any number of highly qualified people who could of answered this question. There are several researchers who study cephalopod behavior and cognition who are generally pretty friendly, and besides that entire societies of researchers devoted to scientificially studying claims of the “supernatural”. CNN is supposed to be credible, right? They’re one of the big names in news, globally. But their reporter didn’t pick anybody who was an expert in the science and psychology behind “parapsychological” phenomena or an expert on cephalopods. Instead, he decided to interview Michelle Childerley (see her personal homepage), a self-proclaimed “Animal Communication Expert
Pet Psychic & Behaviour Specialist.” Her qualifications include thinking that she could talk to her pet dog as a child (who didn’t, though?), as is proclaimed on her “About” page:

Michelle felt since the age of seven that she was aware of a special connection with her dog Jason, her soul mate throughout her childhood. She always knew exactly what Jason was thinking and feeling and would enjoy endless conversations. After Jason was taken away at the age of twelve, Michelle shut down her intuitive awareness for many years to come.
It wasn’t until 2006 that Michelle became aware of her ability once again when the dog of a man selling the big issue suddenly spoke to her. In that moment a reconnection was established and Michelle then set out to bridge the gap between animal and human communication.

(As an aside: what is “the big issue”? I’d love to know.)

So what did Ms. Childerley have to say about Paul? You might have guessed what her take would be. From the CNN article:

Michelle Childerley, who describes herself as an animal communications expert, told CNN that all animals — as well as humans — possess a psychic ability, with telepathy the main way of communicating among many species. She says dogs can often sense what an owner wants before they vocalize it.
As for as Paul’s ability to predict a football result, Childerley claims the octopus is perfectly aware of what he is being asked. “He’s picking up on what everyone around him is thinking,” she said. “He knows there are two boxes which represent two sides, so he’s basically tuned in to the more positive team at the moment he makes his choice.”

Why care about this women and her claims about communications with animals? For one thing, she’s selling these claims to people as a sort of veterinary care, taking money both from misled pet owners and from legitimate practitioners (this is not to say she might not use some legitimate animal training procedures in some of her work, but she will also accept 30 pounds to do an “animal readings/consultations by an emailed or posted photograph”, which means that you send her some money and a picture of your pet, and she will tell you what’s wrong with your pet’s emotional/psychic life. Despite my small knowledge of the field of veterinary medicine, I am sure that this is not a legitimate veterinary care technique.) In addition, claims like hers serve to distract from and give a bad name to people who are trying to work on the sciences of animal communication and animal-human communication. It turns out that communicating with animals in a reproducible and useful way is much more difficult than being paid money to look at a digital image and coming up with a diagnosis and prognosis based on the feeling you get from the image. Pet psychics (especially those who bill themselves with sciencey-sounding titles like “Animal Communications Expert”) give a bad name to the scientists who are working hard to actually understand and explain animal communication and cognition.

The reporter might have redeemed the article if he’d presented any other opinions on the topic, or any indication that readers might want take this “expert’s” testimony with a grain of salt. Sadly, he didn’t. We’re left wondering whether he really took Ms. Childerley’s comments seriously, or if he’s just kind of bad at finding relevant people to interview.

To give credit and links where they are due, I first heard about this story at Boing Boing, where Maggie Koerth-Baker had the right reaction to it: a hearty facepalm.

Thanks for reading!

First and foremost, let it be known that the Circus of the Spineless has rolled into Hectocotyli! It’s a great edition, so be sure to check it out.

The next most important point of discussion: The Octo-Sock. Enough said.

Rounding out my links to enviable cephalopod-related merchandise is this one to Noadi’s art blog, where she makes wonderful polymer clay jewelry inspired by our fine fan-armed friends.

Here’s a neat little story about a floppy little octopus found in South Wales. I love local news outlets – without them I’d have no cephalopod-related news at all!

This next piece of news isn’t cephalopod-specific, but it got me so mad I have to include it. BP is now saying that “if lawmakers pass legislation that bars the company from getting new offshore drilling permits, it may not have the money to pay for all the damages caused by its oil spill in the Gulf of Mexico.” I might be missing something, but isn’t that what caused this problem in the first place? With another oil rig exploding (fortunately it’s not leaking, it’s claimed,) I hope BP (and government agencies, for that matter) don’t ever wonder why people distrust the oil industry. Stop driving so much, people!

New this week in amateur cephalopod video, check out this great clip of a group (school? shoal? could somebody who knows these things tell me which would be correct?) of squid in Bonaire:

Finally, here’s a great video on how to dissect a squid (more properly, on how to teach people to dissect a squid.)

Thanks for reading!

To start off, I’m really happy with how this series came out, and all of the interest it’s garnered in the topic. The time has come, however, to wrap up my writings on consciousness in cephalopods (for the moment, at least.)

In the first three parts of this series (found here, here, and here) I threw a lot of facts out at you. At the end of it all, I’m left with the impression that what’s unique about the argument for the possibility of cephalopod consciousness is, like the arguments for the possibility of various types of conscioussness in many animals, are easily rejected on philosophical or ideological grounds. Importantly, all of the arguments for “cephalopod consciousness” are actually arguments for the possibility that cephalopods might be consciousness – this is something I’ve tried to emphasize throughout. Because these arguments are based on behaviors that are somewhat poorly studied, and have even more poorly studied neural correlates, all the arguments from analogy in the world will have a hard time conclusively confirming or disproving the existence of consciousness in cephalopods, at until the neural basis of consciousness is closer to being solved (assuming, of course, that it can be solved – we’re all materialists here, right?)

As a scientist, I find that two questions are important in this problem.

The first question: Do cephalopods have consciousness, and what are its characteristics? This is a very difficult question to answer. In fact, I remain unconvinced of any answer to this question. They types of experiments that we would need to answer this question have mostly not been done yet. It seems to early to claim a positive answer to this question, but the evidence so far is too suggestive to claim a negative answer to this question. As an insightful commentators on the first post said, it appears that the most scientifically valid answer in this case is “I don’t know.”

The second question is less direct, but more important: Is it possible that cephalopods have consciousness? Phrased another, perhaps more relevant way: Is it likely enough that cephalopods have consciousness to make it worth further study? To this, I can more assuredly say “yes.” Cephalopods have many of the complex behaviors and cognitive abilities that lead us to suspect various levels consciousness in other animals (and in some cases, to do the difficult experiments that are needed to find more direct evidence of this consciousness.) There is definitely a possibility for cephalopod consciousness.

The mild publicity that this series has garnered is heartening, but also a bit frustrating. Several people have linked to me or quoted me and said something like “Cephalopods really are conscious!” (to be fair, many more have accurately represented my position and phrases.) To set the record straight, the arguments I’ve covered are arguments for the possibility of cephalopod consciousness, not for its existence per se. The most important conclusion I have to make about the topic (given my brief period of involvement with it) is that it’s a horrendously complicated question, and one that probably has no simple or easy answer. Even if we could validly say “cephalopods are conscious” it would be difficult to tell what this meant without further clarification of the various states of cephalopod consciousness and their analogs (if any) in mammals (notably, humans.) This sophistication in our ability to study neural and behavioral phenomena is a long way off.

I’d like to add that I don’t believe this is problematic to the ethics of using animals. The uncertainty of the conscious status of cephalopods (or any animal) should not bear heavily on our ethics regarding that animal. Strictly speaking, the conscious status of every organism but myself is somewhat ambiguous to me, as I don’t have direct access to anybody else’s thoughts, experiences, or impressions. However, it does not make sense that I could violently assault some animal (a human, a dog, or a cephalopod) in a way that would cause great pain and suffering if done to myself, and then claim in my defense that there’s no way to prove that the other organism is conscious enough to perceive and suffer from the harm I’ve inflicted on it. Ethical treatment cannot be reserved for those organisms whose consciousness we can prove beyond doubt, because this would exclude every organism besides one’s self. Thus, if there is a reason to suspect that an organism is conscious in any way (that is, has some sort of awareness of its environment and itself that, presumably, could be pleasant or unpleasant) it deserves ethical consideration.

I’d also like to announce that, because this topic seems to be very popular as well as very difficult, I’m working on a series of interviews with researchers who study consciousness in animals (including cephalopods.) I’ve often felt, while writing this series, that I do not have the background to give much insight into the problem, so I decided that it would be best to solicit the insight of some experts in the area! Look for the posts around October; until then, I’ll be taking on other topics.

Finally, I’d like to thank everybody who left a comment on these articles or linked to them – it feels very good to write something that people like, and even better to write something that they can have a well-written, involved disagreement with.

Thanks for reading!