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Bruce Taylor
03-12-2015, 02:45 PM
Well, this is pretty cool. :)

It's been known for a while that certain one-celled dinoflagellates possess a complex organ, suspiciously similar to a camera-type eye. It has what looks like a kind of lens (a light-refracting bulb called the "hyalosome"), beneath which sits what has been interpreted as a photoreceptor. A new article explores the organ in detail, and confirms that its "retina" does indeed respond to light, and may be an endosymbiont.

Here are some pics of the little rascal (H = hyalosome; R = retinal body).

http://i282.photobucket.com/albums/kk273/BruceDSTaylor/Erythropsidinium_zpstxuvjnzd.jpg

Like the retinas of animal eyes, this critter's retinal body contains the photosensitive protein rhodopsin. However, the type of rhodopsin found here points to a prokaryotic source. Suspecting that it might be an endosymbiont (like chloroplasts and mitochondria), the researchers stained it with DAPI, which binds to DNA. The retinal body (R in the following image) took up the stain, which indicates that it has its own DNA. They even caught one in the act of dividing, like a chloroplast or mitochondrion.

A pic of a DAPI-stained dinoflagellate (N = cell nucleus; H = hyalosome ("lens"); R = Retinal Body) Note the bright spot at R.

http://i282.photobucket.com/albums/kk273/BruceDSTaylor/Retinal%20body%20dna_zpsbtgfjydd.jpg

An excerpt:


We have shown that the ocelloid contains two elements which are fundamental to a functional
camera-type eye; a photoreceptor (the retinal body) and a refractive lens (the hyalosome).
Jonasova and Kozmik stated that “Lens-containing (camera-type) eyes can simply be
defined as those with an additional refractive element in front of the photoreceptive layer”[22].
This definition clearly supports our idea that the ocelloid of warnowiids is a functional cameratype
eye.

The whole article is here (PLOS ONE, so no paywall!): http://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0118415

PhaseLockedLoop
03-12-2015, 02:51 PM
And all in one cell! It's so damn small, you can't tell me God didn't design it! :d

BrianY
03-12-2015, 03:01 PM
"ocelloid of warnowiids" now that's a mouth full!BY:D

Bruce Taylor
03-12-2015, 03:25 PM
"ocelloid of warnowiids" now that's a mouth full!BY:D

Yeah, the vocabulary is pretty off-putting. Still, it's an amazing proposition, if true: one microbe serving as a symbiotic camera-type eye for another. Freaky stuff. :D

BrianY
03-12-2015, 03:45 PM
Yeah, the vocabulary is pretty off-putting. Still, it's an amazing proposition, if true: one microbe serving as a symbiotic camera-type eye for another. Freaky stuff. :D

I guess this will put some pretty big holes in the Intelligent Design argument about the impossibility of the evolution of the eye...

Keith Wilson
03-12-2015, 03:53 PM
That's very cool! I remember the first time I read about mitochondria and chloroplasts as endosymbionts; still an amazing idea.

Peerie Maa
03-12-2015, 04:17 PM
Bruce,
Anything known about its lifestyle?

Does vision make it a hunter, an avoider, or does it just use it to follow the light?

johnw
03-12-2015, 04:44 PM
Bruce,
Anything known about its lifestyle?

Does vision make it a hunter, an avoider, or does it just use it to follow the light?

I believe this is one of the voyeur species.

Bruce Taylor
03-12-2015, 08:19 PM
Bruce,
Anything known about its lifestyle?

Does vision make it a hunter, an avoider, or does it just use it to follow the light?

Good question. I gather they're heterotrophs (probably bacterivores, but I don't know much about dinoflagellates....ciliates are my thing). A few years ago, as I recall, there was some speculation that the ocelloid might be capable of resolving an image (which would indeed be handy, for a hunter). But it seems more likely that it serves to amplify and focus small amounts of light, enabling the critter to orient itself in the deep dark depths. Of course, a great many unicellular critters have light-sensing organs and pigments of one kind or another. The ability to seek or avoid light has irresistable advantages. If you're a bottom feeder, light avoidance (negative phototaxis) might be handy for finding your way down. If you're a phototroph, or if you just like to eat green things, light seeking is obviously a good skill to have. And organisms that move up and down the water column on a daily cycle need to know which way to go. So, simple "eyespots" and "stigmas" are a pretty common piece of gear.

WszystekPoTrochu
03-12-2015, 08:38 PM
I guess this will put some pretty big holes in the Intelligent Design argument about the impossibility of the evolution of the eye...

Ain't You mixing intelligent design with creationism? Isn't intelligent design allowing evolution, only steered?

BrianY
03-12-2015, 09:33 PM
Ain't You mixing intelligent design with creationism? Isn't intelligent design allowing evolution, only steered?

Intelligent design is essentially creationism only the proponents of the theory insist that the "intelligence" behind the "design" is unknown or unspecified. It might be the biblical God or it might be some other "intelligent designer". They may agree that evolution is the way the designer created life in the universe, but they still insist that evolution without some directing intelligence behind it cannot account for the "complexity" of life.

ID theory cloaks itself in reason and "science" but it rests entirely on non-scentific, unreasonable assumptions. Proponents of ID insist that a complex structure like the eye could not have evolved. Instead, they say that it must have been "designed" as a fully functioning unit. Their argument is commonly summed up by the question "what good is half ( i.e. One that is more rudimentary than what exists now) an eye?" Of course, this line of reasoning completely ignores the fact that even a rudimentary eye - something that can only detect variations in light intensity, for example - can be a great advantage for an organism. They also make the mistake of assuming that evolution works in a progressive, step by step manner towards a defined goal and until all of the parts have reached their fully functioning state that we see today, they confer no benefit to an organism. They make the additional faulty assumption of assuming that life as we know it today is the endpoint, the "destination" of evolution and they cannot understand that all life is "transitional" between what it was and what it will be in the future.

The biggest problem with ID is the assertion that there is an Intelligent Designer in the first place. ID is grounded on the certainty that all complex things require an intelligent creator/designer. Which begs the question, who or what designed the designer?

WszystekPoTrochu
03-12-2015, 09:44 PM
Intelligent design is essentially creationism only the proponents of the theory insist that the "intelligence" behind the "design" is unknown or unspecified. It might be the biblical God or it might be some other "intelligent designer". They may agree that evolution is the way the designer created life in the universe, but they still insist that evolution without some directing intelligence behind it cannot account for the "complexity" of life.

ID theory cloaks itself in reason and "science" but it rests entirely on non-scentific, unreasonable assumptions. Proponents of ID insist that a complex structure like the eye could not have evolved. Instead, they say that it must have been "designed" as a fully functioning unit. Their argument is commonly summed up by the question "what good is half ( i.e. One that is more rudimentary than what exists now) an eye?" Of course, this line of reasoning completely ignores the fact that even a rudimentary eye - something that can only detect variations in light intensity, for example - can be a great advantage for an organism. They also make the mistake of assuming that evolution works in a progressive, step by step manner towards a defined goal and until all of the parts have reached their fully functioning state that we see today, they confer no benefit to an organism. They make the additional faulty assumption of assuming that life as we know it today is the endpoint, the "destination" of evolution and they cannot understand that all life is "transitional" between what it was and what it will be in the future.

The biggest problem with ID is the assertion that there is an Intelligent Designer in the first place. ID is grounded on the certainty that all complex things require an intelligent creator/designer. Which begs the question, who or what designed the designer?



The second way is from the nature of the efficient cause. In the world of sense we find there is an order of efficient causes. There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be prior to itself, which is impossible. Now in efficient causes it is not possible to go on to infinity, because in all efficient causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate cause, whether the intermediate cause be several, or only one. Now to take away the cause is to take away the effect. Therefore, if there be no first cause among efficient causes, there will be no ultimate, nor any intermediate cause. But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate efficient causes; all of which is plainly false. Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.

I cannot agree with #5 in any way - if one claimes steered evolution to happen, finding ophtalmoid structure somewhere is simply yet another evolutionary pathway to eyes - they have been developed independantly many times. How does making n+1 pathways disprove claims that n or n+1 pathways were steered?

Bruce Taylor
03-12-2015, 10:05 PM
Here's a nice, clear picture of a dinoflagellate ocelloid, by Franz Neidl:

http://www.photomacrography.net/forum/userpix/632_ForumA2971_1.jpg

The ocelloid is that reddish, glassy bulb in the middle of the creature. The red colour is from the photosensitive "retina," underneath the clear bulb.

BrianY
03-12-2015, 10:23 PM
I cannot agree with #5 in any way - if one claimes steered evolution to happen, finding ophtalmoid structure somewhere is simply yet another evolutionary pathway to eyes - they have been developed independantly many times. How does making n+1 pathways disprove claims that n or n+1 pathways were steered?

you need to read up on Intelligent Design and the concept of "Irreducible Complexity" and how ID'ers use that concept to "prove" that eyes cannot have evolved. Basically, the idea is that a complex structure such as the eye depends on all of it's component parts working perfectly and at the same time for the structure to function. If any single part does not work perfectly or is not present, then the whole structure is useless. The implication is that the whole structure must have evolved (or have been designed) all together at the same time towards the same "goal" The discovery in the OP shows that this "eye" is the result of the combination of two independently-evolved structures/things/doohickeys (I don't know what to call them). For some reason, these organisms have taken a bit originally from something outside of themselves and figured out how to put it to use in a way that gives them a survival advantage. Could a supernatural entity of some sort have directed these organisms to take on these bits from outside themselves and use them this way? Sure. But that's not what "Intelligent Design Theory" and "Irreducible Complexity" says should happen - it's not supposed to work like that.

Peerie Maa
03-13-2015, 03:46 AM
I cannot agree with #5 in any way - if one claimes steered evolution to happen, finding ophtalmoid structure somewhere is simply yet another evolutionary pathway to eyes - they have been developed independantly many times. How does making n+1 pathways disprove claims that n or n+1 pathways were steered?The Wedge Strategy (http://www.antievolution.org/features/wedge.html) is why Intellegent Design is being pushed in the US. The link sets out the aims of the antiscience organisation.

WszystekPoTrochu
03-13-2015, 05:22 AM
The Wedge Strategy (http://www.antievolution.org/features/wedge.html) is why Intellegent Design is being pushed in the US. The link sets out the aims of the antiscience organisation.

Ok, I've skimmed through the text and I see it exactly as pointless as it is to try proving or disproving the existence of God using scientific methods.
It is equally pointless to try disprove the theories of either random evolution or intelligent design. You cannot prove that minor changes were done by random chance alone, or that the particular mutation was anyhow favored by divine intervention. It's simply not doable.
I do like the idea of keeping faith in science, but data (these from proper science) are not something to argue with - the choice should be admiring God for the beauty of His works and/or admiring the underlying simplicity of laws leading to superbly complicated reality. I choose both.
I do not see anti-science in what You linked - if publications are kept as scientific as "materialistic" science, adding some mentality tweaks should be ok. Why not?


You need to read up on Intelligent Design and the concept of "Irreducible Complexity" and how ID'ers use that concept to "prove" that eyes cannot have evolved. Basically, the idea is that a complex structure such as the eye depends on all of it's component parts working perfectly and at the same time for the structure to function. If any single part does not work perfectly or is not present, then the whole structure is useless.

To be fair, there are lots of stuff we still do not understand - our imagination and rational thinking could not conceive a plausible explanation for half-evolved organs too complicated to appear after a random mutation or two. Some of them may be caused by pleiotropy, maybe.
The eyes are way more simple than they appear, and their evolution is well explained - photosensible regions of skin becoming small cavities, thus detecting direction of light source. Deepening cavity can be then closed with membrane to keep it safe, and filled with liquid in yet another step. Simple and straighforward, evolving muscles is the tricky part. Maybe that's why not all organisms did that step.

Peerie Maa
03-13-2015, 06:11 AM
Ok, I've skimmed through the text and I see it exactly as pointless as it is to try proving or disproving the existence of God using scientific methods.It is equally pointless to try disprove the theories of either random evolution or intelligent design. You cannot prove that minor changes were done by random chance alone, or that the particular mutation was anyhow favored by divine intervention. It's simply not doable.I do like the idea of keeping faith in science, but data (these from proper science) are not something to argue with - the choice should be admiring God for the beauty of His works and/or admiring the underlying simplicity of laws leading to superbly complicated reality. I choose both.I do not see anti-science in what You linked - if publications are kept as scientific as "materialistic" science, adding some mentality tweaks should be ok. Why not?They are anti science when the science disagrees with their conservative christianity. They have a political agenda to discredit science in the US. Their pundits use the language of science to pedal notsience, especially their opposition to the science of evolution. See http://rationalwiki.org/wiki/Discovery_Institute

S/V Laura Ellen
03-13-2015, 06:23 AM
And all in one cell! It's so damn small, you can't tell me God didn't design it! :d

God didn't design it!

Keith Wilson
03-13-2015, 07:16 AM
Ok, I've skimmed through the text and I see it exactly as pointless as it is to try proving or disproving the existence of God using scientific methods. It is equally pointless to try disprove the theories of either random evolution or intelligent design. You cannot prove that minor changes were done by random chance alone, or that the particular mutation was anyhow favored by divine intervention. It's simply not doable.Yes, I agree. Quite reasonable, but you're Roman Catholic (I presume). 'Intelligent design' i.e. trying to prove God's existence through biology, and in the extreme case biblical literalism, is mainly a US fundamentalist Protestant failing.

WszystekPoTrochu
03-13-2015, 08:17 AM
Yes, I agree. Quite reasonable, but you're Roman Catholic (I presume). 'Intelligent design' i.e. trying to prove God's existence through biology, and in the extreme case biblical literalism, is mainly a US fundamentalist Protestant failing.

Yet another case when I get mocked for idiocies of schismatics ;)

Jim Mahan
03-13-2015, 08:39 AM
Like evolution, creation wasn't an event, all said and done, once, a long time ago. Evolution is creation. It has been happening since forever and continues, like geologic or astronomic processes; all the physical crap in the universe is still revolving, spinning, expanding and cooling since TBB. The 'intelligence' isn't an outside force that started things up and is watching how it goes, trying to make sure that some humans will get there in time so we can all be done and apply for the pearly gates access, all based on what sort of behavior has been somehow pleasing to that Creator. Rather it is a current driving force, the primal force, of everything that is evolving—being created. It's not the old man in the sky, and it's not 'turtles all the way down.' To paraphrase Wayne Dyer, creation is what God is doing right now.

Pretty stupid to spend any energy trying to find a way to prove God, when we obviously have so much on our plates just trying to understand how things, like geology and astronomy and genetics, are here and now, and how things might be a hundred or a thousand or more years from now. (Just a bigger view on 'now.') Mitochondria may be the most successful organism in Earth's evolution. Just look at how it invented and used earthly fauna, for instance, humans, to propagate. Just like how corn has subjugated human existence by inventing agriculture so it could take over the flora side of the planet. Vicious little parasites sucking all the solar energy off our sun.