What is Vampire ? part 3

Physiology

Vampire (Edward) displaying the enhanced muscle structure.

After the change, vampires' physical appearance and muscle mass is enhanced and perfected, eye color changes, and they no longer need to breathe, though they often still do so out of habit, and feel uncomfortable without their sense of smell - the first warning of an impending threat or the smell of potential prey. The ability to cut off airflow from their lungs allows them to remain submerged underwater for as long as they wish, and contributes greatly to their excellent swimming capabilities.
Vampires have uncannily powerful senses. As they grow older and more disciplined, vampires can learn to smell differences between the scents of various humans' blood, as well as scents of other things (like fabrics - the unique scent of denim). The range of their senses can be increased (thought only fractionally) through concentration.
They can hear sounds coming from several miles away, and even with their eyes closed, they can be sure that there are multiple people in a room thanks to their varied breathing patterns. They can hear the sound of a heartbeat, a pulse thudding in a vein, and words spoken too quietly or too fast for humans to detect.
Their enhanced vision allows them to see the smallest details, and extends into the ultraviolet region of the light spectrum. Vampire vision is unhindered by darkness, and is so acute that they view humans as blind, or "mud-eyed", in comparison. Bella describes her sight as being better than an eagle's. Vampires find wearing glasses or contact lenses to be uncomfortable or irritating because they see the miniature imperfections (ex. scratches).
Their bodily scent is based on their venom, and is pleasant, not only to humans, but to other vampires as well.
Their body's natural changes no longer occur. They cannot age or grow (things such as fingernails, toenails, and hair will no longer be able to grow - if they are cut they will never grow back. However, if an arm, leg, nose, or other such appendage should be removed [still painfully], it can be easily reattached. Since the venom is adhesive, coating the severed end with it will help it heal faster). They show no physical or mental illnesses and defects, and their voice becomes more alluring, melodic, and seductive. Their heart no longer beats.
The venom, and venom based liquids replace all of the natural chemical processes and functions in the body. It wets and pools in the mouth instead of saliva. It coats the eyes, burning through contacts after only a few hours, protecting them from damage and thus eliminating all necessity and reason to produce tears. It also lubricates them, allowing them to move around more easily within their sockets. A similar venom based liquid lubricates between the vampires cells allowing their hard stone bodies to move. If a vampire were to remain motionless over thousands of years, dust will actually begin to petrify in response to the venom based liquids, turning their skin powdery and similar to shale in texture, as well as their eyes which develop a milky film over their red irises making the eyes appear pink in color. This can be seen with the ancient Volturi members. These imperfections, however, do not affect the vampires impenetrability or compromise their vision, a vampire that stays motionless would be just as indestructible and sharp as a vampire remaining active.
As vampires describe themselves, they are unchanging, "living stone" beings frozen exactly as they were when they were transformed. (Though to another vampire, the granite-skin feels smooth, soft, and warm and not the icy-hard touch a human would feel). Requiring little or no change to produce sperm, males can still breed, while female vampires cannot, their bodies no longer accommodate the changes related to pregnancy. In male vampires, the venom takes on a form so similar to seminal fluid that can bond with a human ovum, making possible the creation of a human-vampire hybrid. The underlying biochemistry and physiology is currently unknown.
Vampires, although essentially immortal and indestructible, can be killed. Even a human could accomplish it under the right circumstances - venom and venom-based fluids are very flammable. However, humans are unable to compete with vampires in strength and speed, therefore they are unlikely to succeed. If a human were to succeed in lighting a vampire on fire , the vampire could simply take a quick high-speed bound to put it out. This is why it is necessary to rip a vampire's body to pieces before incinerating them into ashes, to prevent them from putting out the fire before it can do serious damage. This is the only known way to kill a vampire.
Thankr to their much greater physical abilities, Children of the Moon and shape-shifters are instead much better equipped to kill a vampire.

Lifestyles

Though there are a range of vampire lifestyles, the most common is nomadic. The majority of vampires move frequently, never settling permanently in one place. This pattern is partly an attempt to hide from the notice of humans. If too many humans disappear from one area, suspicion might be aroused and the Volturi might take notice. Also, if a vampire interacts regularly with humans, eventually the humans will notice that the vampire isn't aging. Another aspect is boredom. Vampire lives are so long that many keep up a continuous search for novelty.
A few covens are exceptions to this rule, and maintain semi-permanent or permanent homes. Doing this requires a great deal of subterfuge - if the coven wants to avoid suspicion and keep the Volturi from becoming involved - and most vampires don't care for the hassle.

Psychology

When a human becomes a vampire, all of his natural behavior, needs and characteristics are frozen within him forever, though they are also heightened at the same time. From the moment a vampire is made, his interests, dislikes and personality is permanently petrified. For instance, if a human with a loving character becomes a vampire, his or her passion is magnified, allowing him or her to love others even more intensely. Another example is if the human was ambitious and cunning, those characteristics become magnified as a vampire, thus making him a ruthless killer. The only aspect that does change is a vampire's outlook on the world.
Aside from their original personalities, they also have ferocious instincts and a compelling drive for consuming blood. The moment they give in to their thirst, all of their characteristics disappear and they could risk hurting one another by competing for the prey. The longer they abstain from blood completely, the harder it becomes for them to resist, and eventually they will give in to their thirst.
Once a vampire falls in love, that feeling never fades and that love is bound for eternity. As a general rule, only the bond between mates is strong enough to survive the competitive drive for blood. Larger covens are less stable, and usually end because of internal violencd. It is possible for a vampire to fall in love after he'd been turned, and that love will be just as permanent as any other.

Driven by fury and grief at James's death, Victoria prepares to attack Bella and Edward.

Another prevalent vampire trait is that of a vengeful nature. Related again to their unchanging state, vampires are not forgiving; they do not move past an insult or injury. The most common example of vampire vengeance is the aftermath of the loss of a mate. When a vampire loses his mate, he never recovers from the pain. He cannot rest until the party responsible is eradicated. Centuries can pass without lessening the ferocity of his need for vengeance. However, it is possible to suppress that desire if they compel themselves to focus.
The second bonding force, and one that is able to keep a large coven stable, is ambition. Vampires are competitive by nature, and some vampires have been able to evolve this competitive disposition into a greater cause capable of uniting many individuals into a secure whole. The pursuit of power is that bonding cause for vampires. The Romanians were the first to do this successfully for a significant length of time.
The third, and rarest, bonding force is the vampire conscience. Very few vampires are born with or develop a value for human life. The consumption of human blood is such a known aspect of vampire life that few ever question it; the driving thirst for human blood seems irresistible. However, those who do learn to value human life in spite of this reality are able to subsist on animal blood. Vampires who live this way are sometimes referred to as "vegetarians". Animal blood is unappealing to vampires, and thus a difficult diet to maintain. Those who make the sacrifice, though, experience related benefits. In the absence of human blood, the competitive drive disappears. Vampires are able to form bonds of love in addition to the bond between mates. The weak coven alliance is replaced by a strong, family-style union. The Olympic and Denali covens are the only two groups to havd successfully adjusted to this diet.

Transformation

"The warmth inside my heart got more and more real, warmer and warmer. Hotter. The heat was so real it was hard to believe I was imagining it. Hotter. Uncomfortable now. Too hot. Much, much too hot."

―Bella

Esme Cullen being transformed into a vampire by Carlisle Cullen.

In Twilight, transformation from human to vampire is described as being "the sharpest memory they have of their human life." A human is bitten, and venom from glands inside the vampire's mouth is injected into the bloodstream.
Depending upon "how much venom is in the bloodstream, and how close the venom is until it enters the heart", the transformation could last anywhere from 2-5 days. During this time, the human will endure indescribable pain. Once the venom is injected, it is described as being "the beginning of the greatest pain you will ever understand". The venom then has to make its way all through the body. Next through the heart, and it will pump again and again in the heart until it starts meeting itself in the veins. Then it will burn all the veins until the heart stops beating. It moves slower than blood because it is thicker, which makes the transformation long-lasting. Each beat of the heart can only push it so far. The changing/burning process is slow. The venom has to saturate every cell in the body before the process can be completed.
There is no medicine that is strong enough to numb the pain; the best one could do is to immobilize the body.

Weaknesses

"We have to kill him. Rip him apart and burn the pieces."

―Edward

Victoria is beheaded.

In the Twilight universe, vampires are not known to be killed by human effort, are unharmed by sunlight, garlic, holy water, silver, any kind of stake, cross, and can enter homes without permission. Also, any kind of human weapon, including bullets, bounces off of them without any pain or harm done. The only known way to kill a vampire is to dismember his or her body and burn the remains before it can reconstruct itself. Thus their weakness is the strength of their kind or something as strong, which cannot be copied by humans, and fire that consumes them.
In the films, vampires are more vulnerable as they can be killed by severing their heads or biting it off their necks. However, fire is still the only known method to destroy them completely.

What is Vampire? part 2

Eyes

"I saved his eyes for last, knowing that when I looked into them I was likely to lose my train of thought. They were wide, warm with liquid gold, framed by a thick fringe of black lashes. Staring into his eyes always made me feel extraordinary-sort of like my bones were turning spongy. I was also lightheaded, but that could have been because I'd forgotten to keep breathing. Again."

―Bella Swan

A comparison of the eyes of two vampires: the red (Aro) are of a vampire who feeds on humans, and the golden (Jasper) of one who feeds on animals.

A vampire's eye color changes with both his/her age and diet. Newborn vampires show bright red eyes; a diet of human blood would darken them to a rose red color. However, a diet of animal blood would instead dilute the eyes to a golden color. Thirsty vampires show dark, onyx black eyes.
Only the Cullens (the Olympic Coven) and the Denali Coven are known to be vegetarian vampires, feeding only on animal blood. Their eyes are liquid topaz, or honey-golden, reflecting their diet. These eyes, however, are viewed as strange and somewhat unnatural by other vampires whose diet consist of human blood, such as James and Victoria, and whose eyes are of a vivid deep crimson, becoming even more vivid as they continue to feed on human blood, and a darker burgundy as they abstain. Newborn vampires are known for having incredible strength as well as brilliant crimson eyes. Bnth traits are caused by their own blood that still lingers within their tissues, producing the shockingly bright red eyes that "fade slowly over the course of a year" and incredible strength.
Meyer writes that, if a Cullen were to drink human blood, his/her eyes would instantly turn burgundy, and if two weeks were to pass without blood, his/her eyes would grow dark. If he/she were to return to a diet of animal blood, his/her eyes would become dark gold, and a lighter golden color, if they were to continue on animal blood. As a vampire's thirst grows, his/her eyes grow darker with it, until they at last become a coal black. In contrast, as vampires feed, their eyes become lighter. In addition to the thirst, the purplish-black bruises under their eyes become more pronounced as their thirst grows. Though if they have recently fed the bruises becomes less noticeable, and all but disappear (depending on how well-fed they are). The bruises indicate that vampires never sleep.

Teeth

A vampire's teeth appear no different than regular human teeth. They do not possess fangs. However, a vampire's teeth are flawless, unbreakable, and razor sharp at the edges. They are also incredibly strong, able to bite through almost any solid substance including vampire skin. On her first hunt as a vampire, Bella describes biting through a mountain lion's neck like biting through butter.

Abilities and limitations

A vampire's physical and mental abilities far exceed those of a human being. These traits vary between different vampires depending on what they were more capable of as humans. Certain vampires also develop one extra supernatural power that is developed from his strongest trait as a human.

Speed

Vampire (Victoria) running so fast she becomes blurry.

One of the most amazing among their abilities is their speed. They are able to run in excess of a hundred miles per hour, substantially faster than the human eye can see. When vampires run, they become "all but invisible". The Quileute wolves are noted to be one of the few things that can outrun them. This suggests that vampires are meant to move to a new location every so often. We see the speed of all the Cullens again during the baseball game. Emmett is described as "a blur around the bases", and Edward can move so quickly that he is able to intercept a ball that has been hit "like a meteor."
They can lay down and sit up within the same second, almost without having to even think about going through the motions. After being turned into a vampire, Bella describes her movements as being instantaneous.

Strength

"You are so soft, so fragile. I have to mind my actions every moment that we're together so that I don't hurt you. I could kill you quite easily, Bella, simply by accident... I could reach out, meaning to touch your face, and crush your skull by mistake."

―Edward to Bella on his strength

Ddward exerting his strength to save Bella.

Another enhanced trait is their unstoppable physical strength. A vampire is said to be thousands of times stronger than any human, able to lift objects hundreds of times their own weight. Edward feared his strength when first meeting Bella, and explained that there was barely a difference to him in strength between caressing her head and knocking it off. A good example of their strength is seen when Bella decides to arm wrestle Emmett after becoming a vampire. She describes the power in his one arm to be about the same as a cement truck moving downhill at over 60 miles per hour. She beats him, however, because she is a newborn at the time. Newborn vampires are always stronger than older ones, since their strength derives from the lingering human blood left in their body. Diet does not have a massive impact on strength, since it always depends on the individual vampire. A vampire's strength also enables them to leap incredible distances. Edward was able to leap over a 50 yard wide river with ease during Bella's first hunt as a vampire, while Bella was able to leap over twice his distance, while only using slightly over half of her full force.
A diet of human blood makes a vampire stronger than animal blood (though only fractionally). Vampires who feed on animal blood (vegetarian vampires) find that "big game" - predators like bears or wildcats - not only smell more appealing to them, but also make them stronger than the "weaker" blood of herd animals such as deer or cattle. Strength, of course, is not always physical. If a vampire possessed great mental strength and willpower as a human, he will find it easier to control his wild, animalistic instincts. Even so, if a vampire has not fed for a long time, he will be less likely to think clearly and more likely to give in to their thirst, attacking the first living thing he detects and draining it of blood within seconds, all without a single thought (human or animal). If, however, an unlucky human were to be near their vicinity, they will preferably attack him/her rather than the animal.

Senses

Bella exploring her new senses as a vampire.

A vampire's senses (smell, sight, hearing, etc.) are also greatly enhanced, which enables them to see, hear and smell things imperceptible to humans. While running, a vampire can see and sense everything that is around them, making him able to keep tabs of their surroundings and avoid hitting anything unnecessarily. Their sense of sight exeeds by far that of a hawk.
When a vampire hunts, he uses his sense of smell to find a prey and hearing to track its movements. Smell is most intense to vampires, since he can smell the blood of his prey.

Special Abilities

"Yes, well, there are some vampires who have gifts beyond the usual super strength and super senses. You've seen one aspect in... our coven. Gifts are rare - one in fifty, maybe - but everyone is different. There's a huge range of gifts out there, and some of them are more powerful than others."

―Riley

Jane's gift of tormenting illusion.

Most vampires find their key personality characteristics intensified by the vampire transformation in the same way their physical abilities are strengthened, but relatively few have abilities that can be classified as supernatural. More common would be a human with a love of learning becoming a vampire with an insatiable scholarly curiosity, or a human with a deep value for human life becoming a vampire with the strength to avoid human blood.
But a few vampires do develop additional abilities that go beyond the natural. These extra abilities are due to psychic gifts in the original human that are intensified in the resulting vampire. For example, a human who was very sensitive to other people's moods might develop the vampire ability to read thoughts or influence emotions. A human who had some limited precognition might develop into a vampire with a strong ability to see the future. A human with a good instinct for hunting might become a powerful vampire tracker. If a human already possessed a certain supernatural gift, this talent will be amplified many times after he is transformed into a vampire.
The proportion of supernaturally talented vampires to "normal" vampires is greater than the proportion of psychically gifted humans to "normal" humans. This is due to the same factor of temperament that results in more beautiful humans being selected to become vampires. Vampires are also drawn to gifted humans when they look to create companions. Some vampires actively seek out the gifted in the hope of utilizing that extra ability in their coven.
According to Eleazar, most vampire gifts are manifested in the mind, though there are certain exceptions. Benjamin was the best case - his power over the elements of nature is completely physical.
No gift ever works in the exact same way in two vampires, because no person (human or vampire) is ever exactly the same.