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RLDavies
392764.  Wed Aug 13, 2008 8:56 am Reply with quote

I thought it was only the great apes that have definitively passed the mirror test, although I wouldn't be at all surprised about dolphins and elephants. I'm quite sure rats don't have a sense of self-recognition.

One problem, to my mind, is that we're quick to claim humans have an innate ability to recognise their own reflections, choosing to forget that this talent develops over four or five years of growing up with unlimited access to mirrors. This is not comparable with taking a monkey that's never seen a reflective surface in its life and giving it 15 minutes with a mirror.

The mirror test is somewhat problematic in itself. The animal is dabbed on the forehead with paint or something similar, then presented with a mirror. The idea is that if it recognises the reflection as itself, it should show interest in the painted spot on its own body, for instance touching or wiping its forehead. Dabbing with water is used as a control, in case the mere sensation of dampness is the reason for investigation.

Strictly speaking, the animal should also be made to look at another of the same species that has been dabbed. Perhaps seeing someone else with a painted forehead makes you want to check your own? I don't recall reading about any mirror tests that controlled in this way, but I'm not saying they haven't been done.

Water is adequate to control for damp sensations, but it can't control for the smell of the paint, or any other sensations that might arise because of the chemicals in the paint. The only real control would be to use, as a control, paint of a colour that would be unnoticeable against the animal's skin or fur. Even this assumes the animal sees colours in the same way as a human.

There's also the possibility that an animal might recognise itself but show no interest. If it's never seen its reflection before, or only briefly at some time in the past, it may have no idea that its forehead isn't supposed to have a spot.

A sense of self is also not the same thing as an understanding of visual reflections. Vision is a second-string sense for many species. If there were a race of sentient dogs, their self-images would be centred around smell and sound. They would rightly be contemptuous of pitiful humans who can't immediately identify themselves in a scent reflector.

I'm more convinced by other types of observations that demonstrate the presence of a "theory of mind" -- for instance, chimpanzees deliberately lying to their troopmates.

 
Davini994
392779.  Wed Aug 13, 2008 9:16 am Reply with quote

gruff5 wrote:
Izzardesque wrote:
I can barely recognise myself in the mirror some mornings.
I count the number of my tentacles to be sure.


If there is more than one, you aren't an octopus;)

 
gruff5
392958.  Thu Aug 14, 2008 3:29 am Reply with quote

Davini994 wrote:
If there is more than one, you aren't an octopus;)

As in "8" is one number??

 
Davini994
393017.  Thu Aug 14, 2008 5:48 am Reply with quote

No! Octopuses don't have tentacles, they have six arms and two legs.

:)

 
mrpip
393952.  Sun Aug 17, 2008 6:10 am Reply with quote

Tas wrote:
Quote:
Octopi can be taught a trick eg getting the lid off a jam jar, but they will have forgotten how to do the next day and have to be taught all over again.


Source, please? I am curious about this. Has this been shown one way or the other?

:-)

Tas


The claim that they forget everything is nonsense. Octopuses (or octopodes, but never octopi) can indeed learn to perform complex tasks, and they do remember how to do it.

People who keep octopuses in captivity (in zoos and as pets) have reported their octopuses learning when they come home from work, and coming to the top of the tank to take their food from them. They can also learn how to open bottles and jars, and some even toilet-train themselves to an extent - I once came across an account (I'll dig up a link later on) of a pet octopus which defecated before feeding time.

I'm intrigued about how the mirror test would be carried out on octopuses. AIUI coloured dye is used, but this would be impractical in the case of the octopus because

  1. it would simply wash off
  2. octopuses appear to be colourblind, only capable of seeing polarisation
  3. most octopuses (I think excluding W. photogenicus and some others - I'm not sure) are capable of changing colour to reflect their environment or their emotion.


So how do they perform the mirror test on octopuses?

 
gruff5
393985.  Sun Aug 17, 2008 9:03 am Reply with quote

mrpip wrote:
The claim that they forget everything is nonsense. Octopuses (or octopodes, but never octopi) can indeed learn to perform complex tasks, and they do remember how to do it.

People who keep octopuses in captivity (in zoos and as pets) have reported their octopuses learning when they come home from work, and coming to the top of the tank to take their food from them. ....

Sorry, I didn't mean to appear octopus-ist and would never dream of discriminating against them on the basis of limb number ;-)

Surely, the zoo octopi are going to go hungry if they go for food when their keepers have arrived home from work? ;-) ;-)

 
mrpip
393994.  Sun Aug 17, 2008 9:34 am Reply with quote

gruff5 wrote:
mrpip wrote:
The claim that they forget everything is nonsense. Octopuses (or octopodes, but never octopi) can indeed learn to perform complex tasks, and they do remember how to do it.

People who keep octopuses in captivity (in zoos and as pets) have reported their octopuses learning when they come home from work, and coming to the top of the tank to take their food from them. ....

Sorry, I didn't mean to appear octopus-ist and would never dream of discriminating against them on the basis of limb number ;-)

Surely, the zoo octopi are going to go hungry if they go for food when their keepers have arrived home from work? ;-) ;-)


Thing is, as the keepers get home from work, the people on the night shift arrive, with fresh buckets of shrimp, fish and octopus sandwiches made out of communion wafers and squid. Gotcha.

And you said 'octopi' - oh no! (KLAXON) Minus ten points, I'm afraid. Octopus comes from ancient Greek, so it's OK to pluralise it in English (octopuses) or in Greek (octopodes) but never octopi, because that is Latin.

 
RLDavies
394252.  Mon Aug 18, 2008 6:36 am Reply with quote

I remember a newspaper article from within the past few years about an aquarium where fish were disappearing overnight from several of the tanks. It was something of a mystery, since some of the tanks had no carnivorous species in them.

They set up a surveillance camera and found it was the octopus. He'd come out of his own tank, crawl across to one of the nearby tanks, have a midnight snack, then return home.

 
mrpip
394562.  Mon Aug 18, 2008 10:43 pm Reply with quote

RLDavies wrote:
I remember a newspaper article from within the past few years about an aquarium where fish were disappearing overnight from several of the tanks. It was something of a mystery, since some of the tanks had no carnivorous species in them.

They set up a surveillance camera and found it was the octopus. He'd come out of his own tank, crawl across to one of the nearby tanks, have a midnight snack, then return home.


Indeed: they're clever buggers and they'll survive as long as their gills remain wet (so that the O2 exchange can continue). Octopuses are most capable of this as they have long arms and well-positioned eyes (on the 'head', where the mantle joins the arms), whereas cuttlefish and squid are not as dextrous and nautiluses nowhere near as hardy (and also not particularly capable of land-based locomotion).

Often, pet octopuses have escaped from their tanks (often when the keeper has forgotten to reseal the tank), crossed the room, helped themselves to the contents of a feeder tank, a bag of food, etc, and returned. Some, however, dry out before they can complete this little escapade and end up suffocating - they're also not particularly good at crossing carpet. I found this account by a lady who (accidentally) let her pet octopus, Octane, out of the tank - the creature crawled across the carpet for just under five minutes before being returned to its tank, having been discovered covered in hair. The poor thing is now starting to become autophagous. (Mercifully, it was already starting senescence, but although the end will now be quick, it will also be very painful.) It's unclear whether Octane was heading out to grab a sneaky snack, or just to explore (which they do).

Needless to say that they (along with all cephalopods) are extraordinarily difficult pets to keep.

 
Ian Dunn
394775.  Tue Aug 19, 2008 8:29 am Reply with quote

According to recent research, magpies can recognise themselves in a mirror. This makes magpies the first non-mammal to have this ability.

Sources: The BBC and The Independent

 
gruff5
394896.  Tue Aug 19, 2008 2:28 pm Reply with quote

pointless repeat of above link


Last edited by gruff5 on Wed Aug 20, 2008 4:45 am; edited 4 times in total

 
samivel
394943.  Tue Aug 19, 2008 4:11 pm Reply with quote

Is there an echo in here?

...echo in here?

 
gruff5
395124.  Wed Aug 20, 2008 4:46 am Reply with quote

Um, yeah, carelessness on my part

 
mrpip
396617.  Fri Aug 22, 2008 10:33 pm Reply with quote

I think I've found the source for the octopus mirror test, but it's a bit shaky. Linky

It was observed (and apparently filmed) behaviour by a (presumably female) E. dofleini (giant Pacific octopus) where a diver held a mirror in front of the octopus and expected it to react as if another octopus had appeared in front of it. Instead, it began exploring behind the mirror. It's a non-conventional implementation of the test, but it may say something interesting.

This behaviour appears to have been observed in S. officinalis (the European cuttlefish) and as cuttlefish are close relatives of octopuses, it's not unreasonable to say that octopuses may be capable of recognising themselves in a mirror. (The implementation in that article involves introducing a filter and thus changing the polarisation on the mirror, meaning the cuttlefish can see it - cephalopods can only see polarisation, not true 'colour'.)

 
weasley
396807.  Sat Aug 23, 2008 5:06 pm Reply with quote

Can I interject here and contend that mere domestic pets such as cats and dogs may also show some degree of awareness of their own reflection. I make this statement based merely on observation and experience rather than having read (and being able to hyperlink) some deeply scientific paper on canine self-awareness experimentation.

My observations deduce that a kitten will often try to play with, attack or run away from its own reflection but after a while, if exposed to the reflection regularly, will simply ignore the 'other' cat. This suggests to me that they have developed an understanding that the other 'cat' is always there, always copying their movements and is not a threat. Introduce a real other cat though and the antics recommence.

Whilst this does not necessarily suggest a real sense of self-reflection (my cats, for example, never use the mirror to inspect their nether parts - if they did they would more than likely never lick them) it does suggest that they come to an understanding about the cat in the mirror.

 

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