After looking at the science underlying the myth of the werewolf, we cast our scientific gaze towards vampires. The vampire is a creature currently enjoying a considerable resurgence in popular culture. The tale of the vampire dates back to folk tales in 18th century Eastern Europe and entered the mainstream via Bram Stoker’s 1897 novel Dracula. The modern vampire has several easily distinguished characteristics. Elongated eye-teeth, a thirst for blood and violent reactions to sunlight. Ceramic “vampire teeth” are available at your nearest body modification shop, so we’ll focus on the science of the latter characteristics.
Did You Know?
The percentage of a population with specific blood types varies greatly from country to country. The three most common blood types in Canada are A+, O+ or B+ (36, 39 and 7.6 per cent of the population respectively). In India those same types represent 36, 22 and 31 per cent of the population, while in Ireland they make up 47, 26, and 9 per cent of the population respectively.
Blood, as I’m sure you’re aware, is important. It is responsible for distributing oxygen from our lungs to every other part of our body. If, for whatever reason, blood flow to the brain stops, we’d be dead within minutes. This is why blood transfusions are so critical in emergency medicine. However, there is an important caveat when giving blood to someone. If you don’t give them the right type of blood, their body will reject it and cause it to clot. An excellent summary of the ABO blood group system can be found at the American Red Cross website.
A common plot device in tales of modern vampires is for the vampires to manufacture fake blood, which they can consume at their leisure. This idea is founded in a very real and important scientific advancement. The US military’s research arm, DARPA, has found a way to produce type O blood in a lab starting with cells from an umbilical cord. Being able to produce blood that can be given to anyone in an emergency has the potential to save many, many lives on the battlefield and in our hospitals.
Did You Know?
The process of growing blood in a lab is called “pharming”, a portmanteau of pharmacology and farming. The University of Arizona pharms a hepatitis C vaccine in potatoes, and a Canadian company called SemBioSys pharms insulin in safflowers.
We all have a great appreciation for the visible light produced by the sun, but that is just a small part of what the sun produces. The sun produces a wide spectrum of electromagnetic radiation ranging from X-rays (which are very high energy) to radio waves (which are fairly low energy) to visible light (which is somewhere in the middle). Most of the especially harmful, high energy radiation is scrubbed out by the Earth’s atmosphere long before it reaches the Earth’s surface. What gives us most cause for concern is ultraviolet (UV) radiation. UV radiation is responsible for suntans (and sunburns!) as well as more serious problems like skin cancer. It is also, presumably, the UV radiation that vampires fear. A similar condition exists in humans and is called solar urticaria, which is essentially an allergic reaction to sunlight. When an individual with solar urticaria has skin exposed in direct sunlight their skin will become red, raised and itchy (which is a common allergic reaction, called hives). Certainly not as dramatic as the reaction a vampire would have, but similar enough in concept.
Did You Know?
Besides radiation, the sun also produces solar wind. Most notably, the northern lights are produced when solar wind particles collide with the Earth’s magnetic field.
Vampires remain much more fiction than fact, but some of our newer, trendier vampires seem to get ideas right out of the science headlines. It is not often the case, but on occasion the truth is stranger than fiction as we’ll discover when we take a look at the living dead.
Canadian Blood Services - Blood Types
Inheritance of Blood Types and Uses in Determining Paternity
Wired - Darpa's Lab Grown Blood Starts Pumping
Discovery Health - How Solar Urticaria Works
Article first posted April 1, 2011.