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One Variety of Sea Slugs Cuts Out the Energy Middleman
dragonturtle69 writes with this story, short on details but interesting: "These sea slugs, Elysia chlorotica, have evolved the ability to gain energy via photosynthesis. Forget about genetic modifications for sports enhancements. I want to be able to never need to eat again — or do I?"
That was my totally favorite upgrade in Mail Order Monsters - recharge from the sub!
meh
I want to be able to never need to eat again -- or do I?
I'l like the ability to never HAVE to eat again, but I wouldn't want to lose the ability to eat at all. Eating is enjoyable. One would hope that you could control the photosynthesis to keep from getting too fat, though.
Free Martian Whores!
Any other questions that could be easily answered by playing Starcraft?
Stop it, stop it, it's fine. I will *destroy* you.
As everybody knows....
It's not easy being green.
I want to be able to consume as many extra calories as I like, and then radiate the excess as visible light, with radiant area, spectrum and direction under my conscious control.
Or, at least, I'd like to be able to metabolize my food and store excess energy as electric charge, easily transferred to whatever devices are handy.
Once you've "eaten enough algae to steal the necessary chloroplasts", you'll be good to go!
I would happily endure eating algae for X days/weeks/months in order to get photosynthesis going in my body. I realize that I'd have to start going outside, but it sounds like a fair trade off to me.
In a normal plant cell is the chlorophyll produces by the cell and then shuttled to the chloroplast to be used or does the chloroplast itself produce the pigment within it's own membrane? If the latter, I would imagine this gene in the slug is redundant as the creature has to eat algae for the chloroplasts anyways.
No, the statement is essentially correct. The slugs harvest (i.e. gain) energy via trapping photons with chlorophyll. They store that energy as chemical bonds in sugar molecules. They then release the energy as needed by metabolizing the sugar. Photosynthesis is the coupled capturing and storing of energy so saying that it "gains" energy via photosynthesis is a reasonable simplification.
Wouldn't that be a fluke that only needed to happen once? They do point out that the animals also have to get chloroplasts by eating plant material (these are not passed on to offspring), so perhaps they meant to say they aren't sure how they appropriate the chloroplasts. I would agree that's a really good question.
Some species of Sea Slugs have another similar interesting ability -- to adsorb and host nematocysts (stinging cells) from jellyfish and hydrozoans they've eaten, and use them for their own defense. The mechanism is substantially different (foreign cells are sequestered in specialized sacs, compared to the intracellular hosting of an organelle) though.
http://en.wikipedia.org/wiki/Glaucus_atlanticus
Actually the hairs I'm trying to split is the difference between energy and an energy source.
Photosynthesis is not like solar power generation that converts sunlight into a different form of energy (electricity).
Instead it uses the energy to produce an energy source (similar to coal as you point out). This energy source is then metabolized into energy. The sun's energy is used indirectly.
Still it is very cool to see an organism that isn't a plant being able to use the sun for more than just heat.
To summarize the article:
Slugs have somehow included algae DNA with its own, and are now capable of actual photosynthesis. The DNA that was copied didn't code for the creation of chloroplasts, so the slugs have to consume a sufficient amount of algae before they can begin the process.
As long as they are exposed to light for 12 hours per day, they can live without the need for food.
Don't piss on my leg and tell me it is good for me.
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Couldn't you just form an symbiotic relationship with algae or photoplankton, allowing them to live inside you for protection in return for using them for energy? Aren't there already animals that do this?
I've abandoned my search for truth; now I'm just looking for some useful delusions.
What should I say then when I piss on your leg?
William of Ockham had no beard. The most likely explanation is that it was chewed off by squirrels every morning.
I’d say, “hi, did you realise that you’re standing in the toilet?”
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Especially in Third world countries where there is plenty of sun, not much food and not much to do other than subsistence living,. At least it would be enough to get a lot of starving humans through the dry famine months that they get in thrid world countries near the equator.
Sure their skin would be green, but that beats starving to death.
Tsukasa: All I really want, is to be left alone...
FTA: "The sneaky slugs seem to have stolen the genes that enable this skill from algae that they've eaten."
I'm gonna go find and chow down on some ninjas right now, so I gain Real Ultimate Power!!
Slugs have been around for millions of years!
Of course the problem with photosynthesis is it doesn't produce energy that quickly so it'd probably be used by slow moving animals like that. Here's a link http://www.nhm.ku.edu/inverts/ebooks/intro.html
Did you know 80 to 90% of the moderators on slashdot wouldn't recognize a troll even if one dragged them under a bridge.
If you think about the laws of thermodynamics, you will realize that "uses the energy to produce an energy source" is just a confusing way to say "cnoverts the energy to another form and stores it".
Here's the thing. Animal cells have the ability to do a lot of biochemistry, but they have very limited ability to do some exotic chemistry that is essential to animal life. The major example of this is a molecule called adenosine triphosphate, aka ATP. All life uses ATP as an energy source.... lemme back up. Chemical reactions are reversible. To get from the reactants to the products requires that you put in a certain amount of energy to get to an intermediate state, and then you get out a certain amount of energy as it goes to the final state. We generally regard the reactant state as higher-energy than the product state (although that's not necessarily true: if you're consistently pulling out one of the reactants, you'll consistently push the products to become reactants.) Enzymes serve to lower the energy that it takes to go from reactants to products.
There are certain classes of chemical reactions that the body *really* wants to force in one direction, so what happens is we have enyzmes that take reactants and ATP, and by splitting the ATP into adenosine diphosphate and a phosphate group, which releases a *lot* of energy, the reactant - product reaction is driven in the direction the body wants. The thing is: animal cells don't have the ability to make ATP. It's a difficult thing to make, and takes a lot of energy (of course, since it releases a lot of energy when it breaks down, it takes more to make the molecule.) So what animal cells have done is ingest bacteria, which we now call mitochondria: they were captured (maybe a billion years ago) and are now used to do the weird chemistry our cells can't do alone. The bit where eukaryotic (animal and plant) cells captured bacteria is where we developed the ability to be large multicellular creatures, rather than just a few cells sort of cooperating. Plants have done the same thing, twice: both mitochondria and chloroplasts are captured bacteria. Chloroplasts contain the structures that convert the energy of captured photons into high-energy molecules that plants use to drive their complicated reactions.
So, these sea slugs have done two interesting things: they've developed the ability to make their own chlorophyll, which is pretty amazing, the equivalent of finding a plant that can make hemoglobin, and they've managed to accomplish the same sort of symbiotic relationship with cyanobacteria that plants and animals did roughly a billion years ago when they formed mitochondria and chloroplasts. The sea slugs are engaging in convergent evolution and ending up with both plant and (primarily) animal characteristics.
Nostalgia's not what it used to be.
Is this actual, observed evolution? Is this the proof creationists are always demanding?
Yes and no. It is one of thousands of examples of observed evolution, and the process is already well proved. This will not stop the demands, however, since the demands are not made in good faith...
"Convictions are more dangerous enemies of truth than lies."
No, God just invented them with the ability to do this to confuse us all. God loves gettin' his jollies off keep mankind eternally confused.
Tsukasa: All I really want, is to be left alone...
According to TFA: 'In fact, the slugs incorporate the genetic material so well, they pass it on to further generations of slugs." Isn't this the long-discredited (allegedly) Lamarckism? Passing on acquired characteristics to the next generation is Lamarckism. And if this isn't Lamarckism, could someone explain why I am wrong? And how can there be 210 comments and, as far as I can tell, no one else noticed this?
Roger Ebert recently wrote about his life after surgery. He can no longer take anything by mouth. I can't imagine life without taste, but he lives it.
... now back to the bit mines.