Shape-shifter

Description
Shape-shifters, also misleadingly known as werewolves, descend from ancient Spirit Warriors of the Quileutes. Back then, a spirit warrior/chief could leave his body and wander as a spirit, able to blow fierce winds, communicate with animals, and hear each other's thought.

The legend goes that one spirit warrior wanted to use this power to enslave neighboring tribes. Not haveing any of it, his chief banished him from the tribe. One day, the chief left his body in a hiding place to patrol the area for any danger. The banished warrior had followed him and stolen his body, cutting then his own body' throat to prevent the chief's return. The chief wandered for a while in spirit form, watching the thief do unspeakable things on his people. One day, the chief's spirit found a large, handsome wolf in the woods. Though jealous of the wolf's physical form, an idea came to him. He asked the wolf to share his body for him, and the wolf agreed. Rushing back to the village as the wolf, he met a few warriors, and he tried to make himself known by yelping Quileute songs. One of the warriors realized that the wolf was under a spirit's control, and, disobeying the thief's orders not to enter the spirit world, left his body to talk to it. The false chief killed him for the treachery. The real chief became enraged, and lunged forward intending to kill the man; his emotions were too much for the wolf, and it transformed into a magnificent human. The false chief got killed, and everything else got quickly set right. The chief sired many children, and found out that his sons, at the age of manhood, could transform into wolves as well.

That is how the wolves came to be. The whole pack is made of the great - to however many degrees - grandsons of that original wolf. Thus far only one woman, Leah Clearwater, has become a shapeshifter.

Appearance
Shapeshifters' appearance vary in both human and wolf form.

The wolf that scares Laurent away from Bella Swan is described as enormous, as tall as a horse, but thicker and much more muscular, with dagger-like incisors, and a grisly snarl like a prolonged crack of thunder. It is even mistaken for a "bear".

Another wolw is deep gray, still another brown, neither one quite as tall as the first, and a third a "rusty brown monster". Bella focuses on the last one, realizing only later that it has the black-brown, familiar eyes of Jacob Black.

Each wolf is of a different color, which correlates with each wolf's true self. Quil Ateara and Sam Uley joke with one another that Sam's black fur is connected to his "black heart" while Quil's chocolate-brown fur reflects how "sweet" he is. No real explanation of this phenomenon is given.

In Eclipse, we discover that other correlations between human and wolf form exist. Bella asks why Jacob is furrier than the others: "Because my hair is longer." Active shapeshifters therefore crop their hair short.

The "monstrous size" of these creatures is emphasized again and again. This links clearly with the actual changes in the boys as well, which Bella notes, although she doesn’t connect the two together until later. "These were just four really big half-naked boys." As humans, they are around 7'0" tall, and they become bigger, more muscular, harder in look and substance. Their voice deepens much.

They also become very similar in their human appearance and the synchronization of their movements, so that they could be mistaken for "quadruplets".

Speed
Like vampires, shapeshifters can run superhumanly fast. According to Jacob, it is better and faster than a motorcycle, and is "the best part" of being a wolf.

Even in his human form, Jake seems to be faster: "Then he turned and sprinted through the parking lot, across the road, and into the bordering forest. He flitted into the trees, swift and sleek as a deer." In Breaking Dawn, Jake indicates that he can run at speeds of 100 miles per hour. The comparison to the vampires is quite clear, and Bella herself notes that being on Edward's back as he runs is "a hundred times better than the motorcycle."

The wolves caught Laurent, suggesting that they are faster than some vampires; however, they were unable to catch Victoria, indicating that some vampires are just as or faster than a werewolves. Bella says: "I couldn't imagine that—the wolves running faster than a vampire. When the Cullens ran, they all but turned invisible with speed." This may have to do with the werewolves being quadrupeds (using four feet to run) as opposed to bipedal vampires. It seems that speed is their real weapon, along with the exchange of thoughts within the pack.

Their reflexes are also immensely fast: "With stunning speed, Jacob yanked a can opener from the counter and launched it at Jared's head. Jared's hand flicked up faster than I would have thought possible, and he snagged the tool just before it hit his face." Also in Eclipse, at the Quileute bonfire, Paul harassed Jacob to give him his hot dog. When Jacob flung it across the circle, Paul caught it before it landed in the sand. They are certainly quick enough to tear apart one vampire as a pack, regardless of how strong that vampire is.

Strength
In human form, their strength is enhanced, but in wolf form is apparently limitless. Bella notes that Jake handles her "too roughly", and that, when he hugs her, it's so "crushing" that nearly suffocates her. He doesn't seem aware of his strength like the vampires are, but this could well be due to the newness of his phasing. It is worth noting that before he phased, he could only put his arm around Bella and help her back along the trail after the motorcycle accident.

When Jacob discusses being a wolf with her later in the novel, he explains: "It's what we're made for, Bells. We're strong, too." The sounds like the wolves are linked with both strength and ferocity.

Physiology
Werewolves run generally a temperature of about 108°F. Bella feels it first when she believes Jake has got a fever on the way home from the movieseeing trip. "Whoa, Jake—you're burning up!". Vampires show a lower than human temperature; perhaps their physiological make up reflects the tension between them.

This high temperature allows them to withstand very cold weather and makes it difficult for them to become overheated. This extremely high body temperature also makes it extremely difficult for vampires to harm them in combat, due to vampires being extremely sensitive to high temperatures. After Bella becomes a vampire, she describes Jacob's skin as like touching an open fire and unbearable to touch.

The wolves can heal and regenerate very fast and completely. While not built in stone, these capabilities allow the wolves to continue battling even after serious injury. In some cases, however, this accelerated healing can be detrimental. After Jacob's bones were crushed by a group of newborns in Eclipse, his skeleton healed before Carlisle was able to set his bones, forcing Carlisle to break those that had set wrong to make them to heal properly. In Breaking Dawn, Jacob however comments that even a bullet through his temple might not be enough to kill him.

The actual transformation between human and wolf is described in greatest detail in New Moon. Certainly the initial transformation is not an easy one, and is very disconcerting and confusing.

While their skin is much more durable than that of a human being (to the degree that the bones in Bella's hand are broken when she punches Jacob in the face), it is not granite hard like a vampire's. In their wolf form, their fangs are sharp enough to penetrate the granite hard skin of vampires. Bella witnesses this for herself during the climatic battle in Eclipse when she sees Seth easily biting through Riley's skin.

Tattoo
In the movies New Moon and Eclipse, the members of the pack all wear this tattoo.

http://i199.photobucket.com/albums/aa11/cammochick00/twilight/quiluetetatoo.jpg

The tattoo was created for film merchandise much like the Cullen Crest and Volturi symbol. The tattoo features the image of two wolves.

Phasing
The transformation can happen at any time, and isn't dependent upon a full moon. In young werewolves, the change is involuntary, since they have not yet learned to control it: "'What would happen...if you got too mad?' I whispered. 'I'd turn into a wolf,' he whispered." The effects of this sort of transformation is shown in the relationship between Sam and Emily, and the disfiguring injuries she has suffered.

Transformation or "phasing" is a sudden and violent process. The initial transformation seems to be triggered by anger, and Jake explains that his own phasing was staved off by his happiness with Bella: "I was like a time bomb. You know what set me off? I got back from that movie, and Billy said I looked weird. That was all, but I just snapped. And then I—I exploded. I almost ripped his face off—my own father!". Sam Uley's transformation also supports this, as it "took him two weeks to calm down enough to change back."

Jacob's point of view explains the transformation back into human form: "I ignored him [Jared], closing my eyes and pulling myself together again. It felt like the air was trembling around me, shaking out from me in small waves. I lifted myself up on my hind legs, catching the moment just right so that I was fully upright as I shimmered down into my human self."

Jacob seems to find phasing between wolf and human form easier than most. "Even Sam couldn't have phased on the fly like that. He saw Paul losing it, and it took him, what, half a second to attack? The boy's got gift." He explains later to Bella that this may be due to his ancestry: "It takes some practice to phase back and forth, but it's easier for me… because Ephraim Black was my father's grandfather, and Quil Ateara was my mother's grandfather."

Transformation
Phasing appears only when vampires are in the neighborhood. Jacob explains, "There's no exact age... it just builds and builds and then suddenly—" it appears to occur roughly when a boy reaches manhood, and is certainly accompanied by a sudden growth spurt lasting for about two months.

The wolves were believed to be only male until the transformation of Leah Clearwater, which surprised everyone, even though "she's a direct descendant, all right."

Imprinting
The issue of imprinting is also critical as this is how the shapeshifter finds a soulmate: "It's not like love at first sight, really. It's more like... gravity. When you see her, suddenly it's not the earth holding you here anymore. She does. And nothing matters more than her."

Once a shapeshifter is imprinted, he will feel the need of constant being in her soulmate's presence and to unconditionally give her whatever she wants or needs. Should the imprintee be an infant, the shapeshifter will act as an older brother; romantic feelings will not develop until she comes to age. Imprinting works on both humans but on hybrids. As it happens for Jacob, if a shapeshifter imprints on a hybrid, his hatred for vampire will disappear. It has become law that no werewolf may harm the imprintee of a fellow pack member, as this will lead to destructive inpack fighting.

Senses
Their sense of smell has adjusted to help them identify their one enemy. "'Vampire,' he spit out. 'I can smell it! Dammit!'" It is not clear whether it is heightened in other circumstances, but they certainly know vampires at a distance, finding their smell sickly sweet and repellent.

Their eyes are extremely sharp, and can see very far.

They all have excellent hearing even when in their human form. In Breaking Dawn, Jacob was able to hear Quil playing with Claire at First Beach from his bedroom.

Genetics
While treating Jacob, Carlisle takes a blood sample and runs some tests on it. He finds out that they have 24 pairs of chromosomes, one more pair than a human and one less than a vampire.

Werewolves vs. shape-shifters
While talking to the Volturi in Breaking Dawn, Edward reveals that the wolves of La Push are actually "shape-shifters" and not true werewolves. The original Quileute shape-shifters apparently could have taken the form of any animal, but chose wolves. These other werewolves, or "Children of the Moon" seem to go along with what people usually associate with werewolves. That is, they only change during a full moon, and they usually create another werewolf by infecting a human with a bite (like a vampire) rather than genetically like the Quileutes. Though, according to Edward, they are not harmed by silver bullets. "That was just another one of those myths to make humans feel like they had a sporting chance." Also according to Edward, "There aren't very many of them left. Caius has had them hunted into near extinction."

At the bonfire in Eclipse, the Quileutes say that shape-shifters are a natural enemy of vampires when telling their legend of the original tribe of shape-shifters who suddenly felt antagonism when they smelled a vampire's scent.

It is unknown, whether there are shapeshifters who can turn in animals other than wolves.

Pack behavior
In their wolf form, shapeshifters show the general behavior of wolves, though they retain their human intelligence, memories and character, up to and including showing their human eyes. Pack memers are also telepathically linked with each other, enhancing their coordination during hunts and fights but allowing little or no privacy at any time. The Alphas of two different packs may also communicate telepathically, but they manage to choose what thoughts they share; it appears that subordinates of different packs don't show this ability.

The dominant male, the Alpha, can force the other pack members to obey his orders against their will. So does the Beta, though he can't command his own Alpha. Though implied, it is unknown whether this characteristic is also extended down the pack hierarchy. Alpha status seems related to both lineage and phasing order; it is unclear whether a lower ranking pack member can challenge the Alpha for this status. Jacob never uses his voice to impose his will on his packmates, though he has a stronger power than Sam.

The Quileute packs
In Breaking Dawn, Seth is informed that Bella and Edward have returned home and she has contracted a rare disease. Jacob soon finds out that she is pregnant with Edward's child, instead. Sam and the others fear the harm the child could bring and plan to destroy the Cullens including Bella and her mutant spawn. Jacob and Seth leave Sam's pack and form their own, in defense of the Cullens. They are soon joined by Seth's sister, Leah, who wants to get away from Sam and protect her brother. After the birth of Renesmee, Jacob imprints on her and the shape-shifters' feud with the Cullens is put to an end.

Sam Uley's pack

 * Sam Uley - Alpha
 * Paul
 * Jared
 * Collin
 * Brady
 * Seven unknowns

Jacob Black's pack

 * Jacob Black - Alpha
 * Leah Clearwater - Beta
 * Seth Clearwater
 * Embry Call
 * Quil Ateara