Are you a chimera?

Thousands of years ago, the Greek poet ­Homer wrote about a specific monster with the chest of a lion, the tail of a snake, the midsection of a goat and heads of all three animals. While this is only mythology, and an exaggerated version at that, there are many natural-borne chimeras around today that we may not even know about.

What is a chimera?

From wiki: a chimera is a single organism (usually an animal) that is composed of two or more different populations of genetically distinct cells that originated from different zygotes. Chimeras are formed from four parent cells (two fertilized eggs or early embryos fused together). Each population of cells keeps its own character, resulting in an organism of mixed tissues. Usually, the condition is inherited, but may also be acquired through the infusion of allogeneic hematopoeitic cells (this happens through transplantation or transfusion). The likelihood of offspring being a chimera is increased if it is created via in vitro fertilization.

There is also a form of congenital chimerism (tetragmetic chimerism). In this way, chimerism occurs through the fertilization of two separate ova by two sperm. The two usually then fuse together at the blastocyst or zygote stage. What results is an organism with intermingled DNA. As the organism develops, it can come to possess organs that have different sets of DNA (i.e. it may have the liver composed of one DNA and a kidney of another. It may even have two different blood types). In CSI (the original), this was a particular key plot in "Bloodlines".

The difference in phenotypes may be subtle (e.g., having one eye a different colour from the other, etc.) or completely undetectable. Chimeras may also show, under a certain spectrum of UV light, distinctive marks on the back resembling that of arrow points pointing downwards from the shoulders down to the lower back in what is called Blaschko's lines.

Blaschko lines form from the fact that chimeras start out with two different cells, each with different DNA (and therefore different instructions). The skin of the person is therefore made up of two different sets of instructions on how to colour the skin. The Blaschko's lines result from the fact that some of a chimera's skin cells say to make darker skin and some say to make lighter.

When there is a big difference between the two DNA's instructions on how dark to make the skin, then you get obvious Blaschko's lines. If the differences are subtle, then you may not be able to see the pattern without the aid of an UV light.

While not as rare as once believed, chimeras may be identified by finding two different populations of red cells, or if the zygotes were of opposite sex, either ambiguous genitalia or hermaphroditism (alone or in combination).

In 2003, scientists had begun to blur the lines of chimerism-producing animal-human hybrids-when Chinese scientists at Shanghai Second Medical University successfully fused human cells with rabbit eggs. While the embryos were successful, after several days of being allowed to develop in a laboratory dish, they were destroyed so that the stem cells could be harvested. And in 2004, pigs were created with human blood.

Why?

Because scientists believe that the more human-like the animal, the better research model it makes for testing drugs or possibly growing "spare parts," such as livers, to transplant into humans.

What do you think about chimeras?

Deconstructing Gremlins

With Halloween approaching, I've been watching a lot of movies. On Saturday, I had a movieathon and one of the movies I watched was Gremlins, a movie I had always been curious about, but had never watched before. I would have been about 1 when it came out and we grew up in quite the isolated bubble.

In the movie, the furry creature found in an old antique store in Chinatown is called a Mogwai. Given as a Christmas present, the boy was told 3 very specific rules:

1. keep out of sunlight (will kill it)
2. stay away from water
3. do not feed after midnight

Of course, the three rules are broken. The creature, named Gizmo is a cute little brown and white puff ball with large ears and eyes. Almost immediately you learn that light hurts the Mogwai. It burns them. By accident rule number 2 is broken when water spills on top of Gizmo. In what looks like agony, Gizmo screeches and writhes as little balls of fur pop off. These balls grow and within minutes, there are at least 5 more Mogwai. It's clear that these new ones are different. They have gathered and named a leader, a creature with a white mohawk. They are devious and seek out ways to break the third rule and when they eat after midnight, go into a cocoon stage where they transform--coming out hairless and evil. Although, I suppose they were always evil, but the transformation was the peak of it. They go around terrorizing the town and killing the people.

While the movie was fairly entertaining, I had a hard time ignoring how implausible the movie was. Now, I've argued this movie before but I thought maybe there'd be something in the movie that would put aside my sense of disbelief. No.

Rule number 1: Stay out of the light

I was fine with this rule. There are reasons to stay out of direct sun. Albinism being one of them. Not that Gizmo had any signs of it. If he would, he would have been all white and his eyes would have been redish due to lack of pigmentation. Direct sun would have burned and made life difficult. That doesn't mean that he couldn't have been affected by the UV radiation. Maybe Mogwais are highly sensitive to it. Who knows.

Like most things paranormal, the fight between evil vs good is often portrayed with the evil creature being unable to go out into light. The only thing is that Gizmo is not evil and he can't go out in sunlight.

Rule number 2: Do not get wet

This is where things started to get murky. The moment water was poured on Gizmo he began to reproduce. (He's like a tribble from Star Trek.) Yes he. The move refers to Gizmo by the male pronoun. It's not completely unbelievable. There are some creatures where males reproduce-- i.e. Syngnathid fishes such as sea horses. However, the difference here is that there was no female Mogwai to place the eggs in pouches on him. Not that we know of at least. You assume he was the only one in that antique store but reality is that there could have been more. How many people have come back from the pet store only to find out that their guinea pig or hamster was pregnant?

Anyway, little balls of fur popped off and grew. What this tells me, without there being a female (let's assume for the time being since we don't know), we have to assume reproduction is done asexually (in gremlin form, they look almost reptilian and some are known to reproduce asexually so it's not a far leap) in a form of parthenogenesis. If Gizmo had been a female, things could have been explained easier, but he isn't. Unless he's a hermaphrodite and we just don't know about it, then...maybe...

But in the rule, it said very clearly not to get the mogwai wet because it'll cause this reproduction. I fought this rule and argued until my face turned red. I question how the mogwai supposed to stay hydrated? Obviously they wouldn't have a long life expectancy if they can't drink anything).

But, aside from staying alive there's the whole issue with the 'Add Water, Will Reproduce'. However, there have been studies that have shown that chemical or electrical stimuli have been used to cause parthenogenesis in scientific studies. If the mogwai have a natural allergy to water, maybe it created a negative external stimuli, causing this asexual reproduction to occur.

I found a site that suggested that if a mogwai was subjected to water to reproduce, the resulting trauma would affect the offspring. The offspring would be evil. However if a mogwai was prepared and underwent normal reproductive means, then the offspring (Gizmo) would be good. This assumes that they have other means of reproduction. Maybe it's explained in more detail later on in the sequels, but in the first movie, there was no implication whatsoever that they could reproduce any other way other than asexually. I'm also not entirely convinced that the trauma of the 'birth' would affect the resulting offspring that dramatically.

I still think it's crazy, but I'm willing to bend a bit.

Rule number 3: Do not feed after midnight

We know what happens. Feed after midnight and the mogwai goes into a cocoon state where it goes through a metamorphosis into the evil little gremlins. Now there's some debate here on the time. Why? Because technically the day starts at midnight, so when is the proper time to feed it (and what do they eat?)? Are mogwai supposed to never eat? All creatures need to eat and drink to survive. And what about time zones? How does this affect the no eating situation?

But that's not the point. We're not debating whether they eat or not. If you go by the 'trauma caused the evil in the offspring' theory, they would have been evil no matter what, even after they went through the change. I'm not so sure. In the first movie, it implied that eating= evil gremlins. Yes they were devious as furballs, but they weren't trying to kill anyone.

Eating (after midnight), is the catalyst to their transformation into the gremlins. While you don't usually see it in reptiles or mammals, butterflies start off as caterpillars and after a period of eating and whatnot, spins a cocoon and then changes. It could be the same type of transformation.

My only question is what does the transformation offer them that they can't do without fur and looking like Yoda? What do you think?

Zombies Pt 3: the zombie brain

In this part of the zombie series, I decided I wanted to have some fun with the zombie brain (the brain eating kind). Check out Pt 1 about Zombies in Nature and Pt 2 on Zombies in History.

Beyond the "living dead" theory, zombies are characterized primarily by their abnormal but sterotyped behaviours. We can see this particularly in many popular Hollywood movies, where zombies aren't portrayed as reanimated dead, but as living humans infected by a biological pathogen such as a virus. They are alive, but different. However the method of transmission, the person is usually transformed into a single-minded hunting machine with all changes to bodily function serving to locate the prey, capture them and then to feed.

Neuroscience has shown that all thoughts and behaviors are associated with neural activity within the brain. Therefore, the zombie brain would also be similar. It makes no sense for it to be different. Because of the behavioural symptoms shown in movies, we're given clues and can piece some of the them together.

Let's break it down by symptoms:

1. Rage: When you look at zombies, they are always trying to eat people (generally angry I guess if they are to feel something). It's an anger that is directed toward everyone simply because they're human or, the next meal course. According to Oscillatory Thoughts, this behaviour has roots in the primitive parts of the brain that center around flight or fight. In humans not infected, these impulses are suppressed by signals in the lower part of the frontal lobe: the orbitofrontal cortex. It sends inhibitory signals to the amygdala.

Like crocodiles (who is driven by the amygdala--studies show that by damaging it, the flight or fight responses is significantly reduced) zombies would be driven by this. Working with the amygdala, the anterior cingulate cortex dampens the excitability, giving the frontal lobe time to process and think what to do. A zombie would potentially have a damaged anterior cingulate cortex. With it affected, the zombie would be unable to regulate the anger, creating hyper-aggression.


2. Appetite: In the brain, there is an important part that controls feeding. This is the ventromedial hypothalamus. Zombies have an insatiable appetite it seems. They're always hunting for prey to chew on. If zombies were to have damage in this area, they wouldn't know when to stop eating. There have been studies in primates that have shown that damage to this area of the brain causes monkeys to eat anything and uncontrollably.

3. Stumbling/staggering gait:

A zombie isn't the best athlete. They stumble and stagger as they move. The area in the brain responsible for balance and fluid motion is the cerebellum and the basal ganglia. Zombies would probably suffer from some sort of dysfunction, much like cerebellar degeneration such as ataxia.

It's possible that all combined, this could explain the behaviour of zombies. Or at least the ones we know from popular fiction. What other symptoms can you think of?

Zombies Pt 2: Historical Accounts

Last week, I posted about zombies in nature and how it's not all sci-fi and brain eating corpses brought back to life. Such is the tale of Clairvius Narcisse, a man who was allegedly poisoned with the poisons used by a Bokor. In 1962, he "died" and was given a burial. When the Bokor later dug him up, Clairvius was given a paste that at certain doses has hallucinogenic effects that can cause memory loss. He was then forced to work, alongside others, on a sugar plantation until the master's death. Because the doses of the narcotic paste stopped, Clairvius eventually regained his sanity (unlike many others who suffered brain damage). One day in 1980, in a supermarket, Angelina Narcisse was shocked when Clairvius, her brother, walked in.

Accounts of zombies go back even farther. Recently, archaeologists found an 8th century graveyard in Roscommon, Ireland with more than 120 of human skeletons with large stones stuck in their mouths--a ritual researches believe the locals did to stop the dead from returning to walk the Earth as zombies. The bodies in the cemetery dated between the 7th and 14th centuries.

At first, the team of archaeologists thought that they had stumbled across a burial ground for the remains of the victims of the Black Death. Initially, they believed that it possibly could have been related to vampire slayings, where a stake is driven into the heart. During the Middle Ages, the people at the time thought that vampires were believed to spread plague. A stone placed inside the mouth was thought to prevent this, causing the corpse to starve. The only thing against the theory about vampires, was that the vampire culture didn't evolve until the 16th century. Therefore, researchers thought that the act of placing stones in the mouths might have simply acted as a barrier to stop the dead from coming back from the graves, possibly feeding into the theory that the vampires would starve with such methods later on.

One scientist said that the mouth 'was viewed as the main portal for the soul to leave the body upon death. Sometimes, the soul could come back to the body and re-animate it or else an evil spirit could enter the body through the mouth and bring it back to life'.

In fact, many cultures placed something in the mouth of the deceased. Ancient Greeks and Romans, for instances, placed a coin in the the person's mouth before burial, believing that it would be payment for the ferryman who conveyed souls across the river that divided the world of the living from the world of the dead.

There are many practices of putting stone and other objects into the mouth of the deceased. What do you think was going on? Was it to stop the dead from rising? Or some other reason?

(Also, check out this awesome hardware store, taking zombie preparedness to a whole new level!)

Zombies Pt 1: Zombies in nature

Zombies. They're quite popular these days. Movies like Dawn of the Dead, Zombieland, or Residence Evil are everywhere, depicting flesh eating creatures going on a killing spree--either because of a virus, chemical, radiation or some other paranormal explanation. Even the CDC got in on the action and specialized their web-page to prepare you for the zombie apocalypse.

But in reality, zombies have a whole different meaning. The creole word ''zombi' is derived from Nzambi, a West African deity, coming into use in 1929 after the publication of The Magic Island by William B. Seabrook's. The book describes the first 'zombie' Seabrook came across:

"The eyes were the worst. It was not my imagination. They were in truth like the eyes of a dead man, not blind, but staring, unfocused, unseeing. The whole face, for that matter, was bad enough. It was vacant, as if there was nothing behind it. It seemed not only expressionless, but incapable of expression."

Haitian voodoo priests, known as Bokors, study and use black magic to resurrect the deceased. According to local lore, a bokor captures a victim's ti bon ange, or the part of the soul directly connected to an individual, to create a zombie. What the Bokor uses, however, is a powder issued to the victim orally that is often called coup padre. After analyzing the powder, scientists found tetrodoxin (a poison from the puffer fish), a marine toad that also produces a toxic substance, a hyla tree frog, and sometimes, human remains as main ingredients. In addition, some contain other plant and animal ingredients, like lizards and spiders, which would be likely to irritate the skin. Some even included ground glass.

Once the powder gets into the bloodstream, the victim's heart rate begins to slow to a near stop and he/she is perceived as 'dead', despite them only being paralyzed. Thinking the person dead, the public would bury him/her. The victim would then be exhumed by the Bokor. Although alive, the victim's memory would be messed up badly and they are said to be transformed into a mindless drone, often said to be put to work in the fields as slaves.

There are also natural sources of zombie-nism that can be found. Recently, a stalk of fungus species Ophiocordyceps camponoti-balzani was found growing out of a "zombie" ant's head in Brazil. The fungus was found to infect an ant and take over its brain. Once the ant gets to an ideal location for the fungi to grow and spread their spores, the ant is killed.

Another natural "zombie" is created in South America by a female phorid fly. With the use of a needle-like appendage, the female fly will inject their egg into a fire ant. The egg grows and the larva migrates to the ant's head, living there for weeks as it eats at the brain. Sometimes, the ant is compelled to move away from its colony to avoid attack by the other ants. Once it's grown, the fly decapitates its host, exiting through the ant's head.

There's also the case of a parasitic jewel wasp that uses a venom injected into a cockroach's brain to inhibit it of free will. The venom was found to block a chemical substance called octopamine (a brain substance that places insects in an alert state, inspires them to move, and allows them to perform demanding physical tasks) in the cockroach's brain. Unable to fight back, the "zombie" cockroach can be pulled into the wasp's underground lair where an egg is laid in its abdomen. Much like with the fire ant, the larva eats the still living cockroach from the inside out in about seven to eight days.

These are just a few instances of natural zombie-nism and how it could occur. How do you feel about pop culture's obsession with the brain-eating zombies?

Mermaids: Pt 2- Reproduction

Last week I talked about mermaids and how they could potentially see under the water—eyes like fish, not like ours. Today’s discussion is how mermaids could possibly reproduce if they were real. This isn’t going to be a sex-ed. I imagine it’d be something similar to dolphins. However, that wasn’t the question a friend asked me. She asked whether mermaids would lay eggs or have live birth.

Would they take after the fishes, considering they’re fish-like from the waist down or would they take on the live birth like mammals? If we go by the fact, for the moment, that they are fish-like completely from the waist down, then we should assume that their reproductive organs are as well. That would mean that they’d lay eggs. But let’s step back a moment. If mermaids did lay eggs and then were fertilized by the males after, there wouldn’t be much diversity of the species as a whole. Also, fish can lay hundreds of eggs. Even if only half of them hatch, that’s a lot of mermaids. You’d expect a lot more sightings.

Therefore, this leads to the explanation that mermaids would have to take after whales and porpoises= live birth. Not just that, but mermaids have been depicted with mammalian traits (i.e. breasts and a navel). If you account for probably only one baby per pregnancy, maybe two, the odds seem more reasonable. Also, if you look at the depictions of their tails, it closely resembles that of a dolphin rather than a fish.

What about their scales? Dolphins and whales don’t have colourful scales like fish do. I would assume that it is just artistic license. If you look at drawings of dolphins, some are drawn with scales as well and we know they don’t.

So what do you think? If mermaids were real, how do you think they would reproduce? On a fiction note, do you like stories of mermaids?

Time travel-- Impossible or impossible for now?

We've all watched sci-fi shows and movies with time travel where something is either sent backwards in time or forward into the future. In various shows, a person is usually the one going back and forth (usually with the aid of some kind of device). The idea is based on Einstein's general theory of relativity, suggesting that time slows down for objects moving at high speeds. it also suggests that space and time get pulled out of shape near an accelerated or rotating object.

In the 1920s and 1930s, scientists that an infinitely long cylinder spinning at speeds close to the speed of light could be used to warp space-time. Many experiments have been done, including one by Carrol Alley who synchronized two atomic clocks and put one on an airplane. The one on the plane became microseconds behind the one on ground, suggesting that perhaps time had slowed with the speed of the plane.

And in 2001, Ronald Mallet theorized that the gravitational field produced by a laser beam could be manipulated to allow time travel. Wormholes have also been theorized to perhaps allow instant travel from one point to another (whether it's to one point in time to another or one dimension to another).

However, physicists at Hong Kong have recently demonstrated that a photon cannot be accelerated beyond the speed of light, implying that time travel is impossible at least in one area. The research team, working to Einstein's special theory of relativity (that nothing can travel faster than the speed of light) showed that this is true.

What do you think? Do you think time travel is possible through other means? If you could go back in time, where would you go? Or would you go into the future?

Read the article here.

Vampires Pt.4- Why Vampires Can't Exist (second part)

I've been hearing a lot about Vitamin D deficiency recently and how it works to cause osteoporosis and then it came to me... a reason why vampires can't exist. Vampires technically still have the skeletal system of a human. Or they should. There is no real reason why they wouldn't. So wouldn't they still be affected by osteoporosis as well? You get your vitamin D mostly by the sunlight. Vampires don't go out in the sun. So why is there not more vampires with osteoporosis. If you think about it, it's not like they are drinking milk. The only other explanation would be for them to take supplements the rest of their life, otherwise, they'd fall apart.

Just a random thought...