
Weird pupils let octopuses see their colorful gardens - ronald_raygun
http://news.berkeley.edu/2016/07/05/weird-pupils-let-octopuses-see-their-colorful-gardens/
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DavidWanjiru
For a moment there, that headline had me thinking that school kids who happen
to be weird have colorful gardens and are showing these gardens to octopuses.

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passive
I'm not going to click it, and just keep believing this.

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anigbrowl
_[cephalopds] are colorblind – their eyes see only black and white – but their
weirdly shaped pupils may allow them to detect color_

Do PR people ever think about the awfulness of the drivel they write? I see
the point the author is trying to make here but writing self-contradictory
sentences is not the wright approach.

    
    
      Cephalopods, long thought to be color-blind, may in fact be able to detect color....
    
      Although the retinas of cephalopods cannot detect different colors, new research suggests they may be able to detect color another way.
    
      ...etc.

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kkylin
Wow. This is cool. For anyone else who's interested, the full paper is at
[http://www.pnas.org/content/113/29/8206.full](http://www.pnas.org/content/113/29/8206.full)
and supplemental information (including movies) at
[http://www.pnas.org/content/suppl/2016/07/01/1524578113.DCSu...](http://www.pnas.org/content/suppl/2016/07/01/1524578113.DCSupplemental)
.

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jaclaz
The "S1" video is a classic, and every time I see it I do like it again and
again.

The original is AFAIK by Roger Hanlon:

[https://www.youtube.com/watch?v=aoCzZHcwKxI](https://www.youtube.com/watch?v=aoCzZHcwKxI)

[http://www.mbl.edu/bell/current-
faculty/hanlon/](http://www.mbl.edu/bell/current-faculty/hanlon/)

Who has published a few more nice videos here:

[http://www.mbl.edu/bell/current-
faculty/hanlon/videos/](http://www.mbl.edu/bell/current-
faculty/hanlon/videos/)

~~~
kkylin
I hadn't seen these before. They're great. Thanks!

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roryisok
Took me a second. "why would students be showing a garden to an octopus?"

Oh, and I love your username op. My brother started a comic with that same
title, never did finish it

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mastazi
> why would students be showing a garden to an octopus?

Well according to the title those students are weird... :-)

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techninja42
What a beautiful hack by nature. I wonder if you could create a lens with a
similarly shaped pupil/iris and see the chromatic aberration in a black and
white camera correctly focused on the output. Would make for a fun weekend
project :)

~~~
kirykl
Maybe possible to use this technique on space probes to capture true colors in
a single channel, saving on data transfer

~~~
crazydoggers
This was brilliant to me at first blush. After thinking about it, though,
wouldn't the image have to be a higher resolution to compensate for the
blurring of the chromatic aberration? When you process out the blur to extract
the color information, you'll have less resolution left over. I'm guessing
that would offset the gains on using a single channel. Ultimately for "full
color", at a specific resolution, you need a specific number of bits of
information, regardless if it's encoded in three color channels, or a single
channel.

~~~
kirykl
Yea just throwing it out there. I think you're right it would most likely
require more data

~~~
taneq
It might still be good for other reasons, though. Like if the colour filters
used in space probes degrade over time (I don't know, do they?) then it would
allow more consistent colour recording. Also it might be usable on very small
probes that primarily take black and white images but can capture colour (at
expense of resolution) if required.

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11thEarlOfMar
Can't let a post on octopi go by without re-posting this amazing out-of-the-
water predation:

[https://www.youtube.com/watch?v=F5fZu-1bt6Y](https://www.youtube.com/watch?v=F5fZu-1bt6Y)

~~~
xemoka
Octopus does not originate from latin, but instead greek. So it would be
octopodes[0], however, we all speak english, so octopuses is fine. Or, you
know, use what you want because english isn't prescriptive...

[0]: [https://en.oxforddictionaries.com/explore/what-are-the-
plura...](https://en.oxforddictionaries.com/explore/what-are-the-plurals-of-
octopus-hippopotamus-syllabus)

~~~
leephillips
I'm hip. In fact, saltshaker blended diffeomorphism, but rather crispness
loves polarity muchness than tilings. Or not; I'm not really sure.

~~~
taneq
What a hoopy frood you are.

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faitswulff
Fascinating tidbit for those who check the comments first:

> Intriguingly, using chromatic aberration to detect color is more
> computationally intensive than other types of color vision, such as our own,
> and likely requires a lot of brainpower, Stubbs said. This may explain, in
> part, why cephalopods are the most intelligent invertebrates on Earth.

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koliber
Can someone tell me if I am understanding this right? If not, can you clarify?

This is how I understood it:

They don't have different cones cells for detecting color. Instead, their
pupil is more like a slit, causing light to be diffracted, not unlike a prism.
Because of the diffraction, different wavelengths of light fall on different
areas of the retina. Their brain is mapped as such that they understand the
location of the light as the color. Moving the eye around helps them refine
this information.

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amelius
How did they establish that octopuses are colorblind in the first place?

Wouldn't a behavioral test immediately reveal that they are not colorblind?

I'm curious about the scientific process here.

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corecoder
They looked at the retina, and at its lack of color cones.

~~~
dr_zoidberg
I think something similar happened with dogs (no color cones), but then
behavioral tests showed they have some limited color vision.

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corecoder
Are you sure about this? I seem to recall that dogs do have cones, just not
many and not of as many varieties (that is, three) as we have.

~~~
dr_zoidberg
I'm not a biologist nor vet, so not my area of expertise, but there are a lot
of jokes about dogs being colorblind (tv series, movies, etc) and in the end
it happens that they do have some limited color vision. Sorry I can't give any
reference.

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kristopolous
I wonder what their color range is; if I'm reading right, this isn't
necessarily the same spectrum range that we are accustomed to.

