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Parasites


freeztar

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euw, just looked up some links

 

how??

By keeping your immune system occupied with useful stuff instead of overreacting to nonexistent dangers and causing the problems you mentioned. We evolved with parasites, and our bodies are geared to maintain a truce, albeit uneasy, with them. It has been found that some animals, including zebras, sicken and eventually die if purged of their parasites.
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I saw this on TV and was absolutely fascinated. The parasite is the Dicrocoelium dendriticum and it moves from cow to snail to ant back to cow. I'll let you read the article below, but the punch line is how the parasite takes control of the ant's mind.

 

It is unimaginable to me how this parasite evolved.

 

From Mind control, ants, and parasites (thing)@Everything2.com

Meet Dicrocoelium, a fellow parasite.

This lancet fluke's lifestyle is a migration through the fluids of three hosts; a cow, a snail and an ant.

Hungry snails eat the dung of the infected cows and swallow inadvertently the sequestered fluke eggs. Once hatching in the snail's intestine, they burrow through the gut wall and into a digestive gland. Within this gland, flukes reproduce a second generation - spewed back into the world by the tormented snail as balls of slime, each sticky drop, a seething mass of flukes.

It is in the third host, the ant host, where we observe mind control. Foraging ants come across the sparkling orbs of snot, sensing the source of moisture that they are, they quench their thirst on the slick beverage. Entering the third hypersea reservoir, the flukes undulate through the ant's fluids, most form cysts in the abdomen, but some home in on the nerve clusters that control the mandibles in the ants head.

The temperature drops into the coolness of evening, and the infected ant feels compelled to leave its brethren, forsaking them to climb a grass stalk spire to its apex - the pastures emergent canopy. Preparing to make itself a sacrifice, it anchors itself to the flimsy blade, attached firmly by its mandibles.

It waits motionless throughout the night to be devoured by the primary host, the cow. Herds like ruminating clouds pass over the ant, blotting out the stars, the hoof falls reminisant of distant thunderclaps. If the ant survives until morning the flukes relinquish their control allowing the ant to scurry back to join its fellow workers in the gloom and away from the solar furnace which would be death to both the host and the backseat driving parasite. By day the ant is a regular Joe indistinguishable from any other ant, but when night falls, again it makes its ascent into 'munch range' over and over until eventually consumed, drowned in cud, bursting open as a swarm of flukes within the cows stomach. The flukes complete the cycle by penetrating the bovines liver, becoming adult egg producers.

Flukes embedded inside another organism, use mind control. Though it could be argued not remote control, but the comparison remains at some level similar, implanting electrodes, the closest we can come to crawling inside another animals CNS. At least hopefully so.

 

-modest

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Wow, that's absolutely amazing!

 

I did some follow up research and found several other parasites with mind controlling abilities.

 

Here is the wiki for Toxoplasma. Apparently this parasite can cause mice to run towards cats rather than away from them. It's also been researched as a cause of schizophrenia.

Toxoplasmosis - Wikipedia, the free encyclopedia

 

Here's a wiki for the cockroach wasp: (I like this wasp!)

Emerald cockroach wasp - Wikipedia, the free encyclopedia

 

As early as the 1940s it was published that wasps of this species sting a roach twice, which modifies the behavior of the prey. A recent study using radioactive labeling proved that the wasp stings precisely into specific ganglia. Ampulex compressa delivers an initial sting to a thoracic ganglion of a roach to mildly paralyze the front legs of the insect. This facilitates the second sting at a carefully chosen spot in the roach's head ganglia (brain), in the section that controls the escape reflex. As a result of this sting, the roach will now fail to produce normal escape responses.

 

The wasp, which is too small to carry the roach, then leads the victim to the wasp's burrow, by pulling one of the roach's antennae in a manner similar to a leash. Once they reach the burrow, the wasp lays an egg on the roach's abdomen and proceeds to fill in the burrow entrance with pebbles, more to keep other predators out than to keep the roach in.

 

The stung roach, its escape reflex disabled, will simply rest in the burrow as the wasp's egg hatches. A hatched larva chews its way into the abdomen of the roach and proceeds to live as an endoparasitoid. Over a period of eight days, the wasp larva consumes the roach's internal organs in an order which guarantees that the roach will stay alive, at least until the larva enters the pupal stage and forms a cocoon inside the roach's body. After about four weeks, the fully-grown wasp will emerge from the roach's body to begin its adult life.

 

And another parasitic wasp that uses mind control:

Hymenoepimecis argyraphaga - Wikipedia, the free encyclopedia

 

The adult female wasp temporarily paralyzes the spider and lays an egg on her abdomen. The egg hatches into a larva which sucks the spider's blood through small holes, while the spider goes on about her normal web building and insect catching behavior for the next one to two weeks. When the larva is ready to pupate, it injects a chemical into the spider, causing her to build a web whose design is completely different from any she has ever made, and then to sit motionless in the middle of this web. The wasp larva then molts, kills the spider with a poison and sucks its body dry before discarding it and building a cocoon that hangs from the middle of the web the spider has just built. The larva pupates inside the cocoon, then emerges to mate and begin the cycle over again.

 

This is too cool, anyone know of any other examples?

I'm with Modest, I can't fathom how these traits could have evolved.

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I'm with Modest, I can't fathom how these traits could have evolved.

 

And, especially when you juxtapose how easily a host could evolve a defensive mechanism compared to the parasite evolving a life-cycle that depends on controlling another species' actions and invading multiple hosts by getting them to interact with each other. For example, with the ant-invading parasite: all the ant needs to add to its genetics is a dislike for snail juice and the parasite is out of luck.

 

then again...

 

Perhaps the parasite's traits that seem so complex evolved in order to counter the defense mechanisms thrown at them. If cows slowly stopped eating ants as a defense mechanism - the parasite could slowly evolve ways of making the ant more accessible. This would maybe end up with the freaky kind of mind-control the parasite inflicts.

 

given enough time...

 

The parasite evolves into an evil race of Goa'uld intent on dominating the galaxy and enslaving mankind ;)

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Strepsiptera are pretty strange, too: They undergo metamorphosis twice, actually extend the lifespan of their host (albeit at a not so small price ;)) and the female mates and gives birth through her head. There's a good description at the Pharyngula website. Unfortunately I'm not allowed to post links yet.

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The little buggers have been around for along time and we still cary some with us!

perhaps we would not be as we are today with out them?

New explanation for how regulatory networks of genes evolved

Medical Science News

Published: Thursday, 15-Nov-2007

 

When ancient retroviruses slipped bits of their DNA into the primate genome millions of years ago, they successfully preserved their own genetic legacy.

 

Today an estimated 8 percent of the human genetic code consists of endogenous retroviruses (ERVs)--the DNA remnants from these so-called "selfish parasites."

New explanation for how regulatory networks of genes evolved

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The little buggers have been around for along time and we still cary some with us!

perhaps we would not be as we are today with out them?

 

New explanation for how regulatory networks of genes evolved

 

There is another article on this in post #33 of this thread. Inasmuch as the little buggers predate us, it strikes me as a parent (apparent :read:) that we are what we are because of them and not inspite of them.

 

Just had to bug you a bit on this one Micha! G'donya for playing. ;) :hihi:

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There is another article on this in post #33 of this thread. Inasmuch as the little buggers predate us, it strikes me as a parent (apparent :read:) that we are what we are because of them and not inspite of them.

 

Just had to bug you a bit on this one Micha! G'donya for playing. ;) :hihi:

Thanks/sorry Turtle I missed that.

 

Don't you find this REALLY mind-bogglingly amazing?

 

I mean the 1% DNA that is the difference between us and chimps is probably parasite?

A parasite that has decided to 'turn on ' some of our genes.

That, therefore, makes us what we are !

And just what is that?

Just who are we? ' a congregation of vapours. . ." -" the quintessence of dust. .'

-a walking bag of an assorted "stamp collection" of various DNAs in water?

Viruses prey upon all living organisms, turning them into virus Xerox machines.

 

"It's not a living organism," said immunologist Fabio Romerio of the Institute of Human Virology, founded and directed by Gallo.

"It's simply a well organized molecular parasite."

Inside Look: How Viruses Invade Us | LiveScience

Today an estimated 8 percent of the human genetic code consists of endogenous retroviruses (ERVs)--the DNA remnants from these so-called "selfish parasites."

New explanation for how regulatory networks of genes evolved

So can a viral parasite jump-start evolution & natural selection?

So could some Homo spaiens (var.X) "X-Men" appear to-morrow?

 

 

Interesting too, how they are discovering that so many cancers & leukaemia are caused by viruses.

Is cancer just a genetic adaptation that failed and killed its host?

 

"The world is not only stranger then we know. It is stranger than we can know."

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Thanks/sorry Turtle I missed that.

 

Don't you find this REALLY mind-bogglingly amazing?

 

...Just who are we? ' a congregation of vapours. . ." -" the quintessence of dust. .'

-a walking bag of an assorted "stamp collection" of various DNAs in water?

 

No worries. Absolutely mind-bogglingly amazingatious to say the least. :read: Your line reminded me of an old Star Trek episode wherein the 'evil' alien refers to the humans as 'bags of water'. So we are. :hihi: Whatever the penultimate knowledge we may have of all the particulars, we peeps make a model model of emergence. Que sera sera.

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I used to sing Que sera sera. (badly)

 

Everytime I get a notification of a new post for this tread I also get a list of people wanting to scare me about parasites and sell me a cure!

Some are pretty scary

SEE

Parasite Picture Gallery

Experts claim that 'some type of worm is already in the intestines of over 75 percent of the world's population'. This is a frightening statement.

That is one mean looking "Alien #3" hookworm

and

Human Intestinal Parasites

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Spanish for "What will be, will be". Also the title of a hit song from way back - by Doris Day, I think.

 

After reading as much as I could about parasites, I've come to the conclusion that if they don't bother you, don't bother them. If they do become troublesome, there are a number of antihelminthics available, but accurate diagnosis of the infection is important.

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Here is some more to worry about

Bilharzia

Robyn Williams: In villages around Uganda and other places in Africa, small creatures infect thousands to make their lives a misery. Dr Russell Stothard is at the Natural History Museum at London, and we're looking at the effects of Bilharzia.

Russell Stothard: Here we have a child who's being bathed in a bucket, and this child is very young, he's perhaps a year-and-a half old, but the parasite doesn't differentiate people by age. So if you're exposed to water infected or infested with the parasite then the parasite will be able to penetrate the skin, and if it's a baby or an adult child or an adolescent, it doesn't make any difference.

Robyn Williams: And this is the creature, is it? Ugh!

Russell Stothard: Yes, these white objects, about the size of the grain of rice, and these are the things which actually live inside your bloodstream around your bladder or your bowel. There's quite a lot of them here, perhaps a couple of hundred, so typically a child might have maybe 50 to 100. But you never actually see these worms because they're trapped away inside the blood vessels. What you do see is the eggs that they produce. So, for example, if you diagnose a child with disease you'd be looking for eggs of this parasite in the child's urine or the stool. It's the eggs in fact that cause the disease because they get trapped in tissues.

 

Robyn Williams: And the tissues then swell, do they?

 

Russell Stothard: Quite so. One of the classic signs of Bilharzia is children who have got a very distended or rounded abdomen or stomach.

I'll show you an image here actually which illustrates the point.

This is a photograph of a child, again, I took in Uganda, but this might be a consequence of this particular child who is about nine years old, he might have been infected when he was very much younger, perhaps, as we saw in the other image, the child being bathed in the bucket, but we see the child here having a very distended abdomen.

That's because the spleen and the liver and often the bowel have become congested with the parasite eggs, and as a consequence the whole organ swells.

Transcript

Science Show - 1December2007 - Bilharzia disease

Listen (for next 3 weeks)

Science Show

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