But that story bears little resemblance to the evidence that scientists have gathered about their evolution. After Landsteiner's discovery of human blood types in , other scientists wondered if the blood of other animals came in different types, too. It turned out that some primate species had blood that mixed nicely with certain human blood types. But for a long time it was hard to know what to make of the findings. The fact that a monkey's blood doesn't clump with my type A blood doesn't necessarily mean that the monkey inherited the same type A gene that I carry from a common ancestor we share.
Type A blood might have evolved more than once. The uncertainty slowly began to dissolve, starting in the s with scientists deciphering the molecular biology of blood types. They found that a single gene, called ABO, is responsible for building the second floor of the blood-type house. The A version of the gene differs by a few key mutations from B.
People with type O blood have mutations in the ABO gene that prevent them from making the enzyme that builds either the A or B antigen. Scientists could then begin comparing the ABO gene from humans to other species.
And they've found that our blood types are profoundly old. Gibbons and humans both have variants for A and B blood types, and those variants come from a common ancestor that lived 20 million years ago. Our blood types might be even older, but it's hard to know how old.
Scientists have yet to analyse the genes of all primates, so they can't see how widespread our own versions are among other species. But the evidence that scientists have gathered so far already reveals a turbulent history to blood types.
In some lineages, mutations have shut down one blood type or another. Chimpanzees, our closest living relatives, have only type A and type O blood. Gorillas, on the other hand, have only B. And even in humans, scientists are finding, mutations have repeatedly arisen that prevent the ABO protein from building a second storey on the blood-type house. These mutations have turned blood types from A or B to O.
Being type A is not a legacy of my proto-farmer ancestors, in other words. It's a legacy of my monkey-like ancestors. Surely, if my blood type has endured for millions of years, it must be providing me with some obvious biological benefit. Otherwise, why do my blood cells bother building such complicated molecular structures?
Yet scientists have struggled to identify what benefit the ABO gene provides. The most striking demonstration of our ignorance about the benefit of blood types came to light in Bombay in If A and B are two-storey buildings, and O is a one-storey bungalow, then these Bombay patients had only an empty building lot. Since its discovery, this condition — called the Bombay phenotype — has turned up in other people, although it remains exceedingly rare. And, as far as scientists can tell, there's no harm that comes from it.
The only known medical risk it presents comes when it's time for a blood transfusion. Those with the Bombay phenotype can only accept blood from other people with the same condition. Even blood type O, supposedly the universal blood type, can kill them. The Bombay phenotype proves that there's no immediate life-or-death advantage to having ABO blood types.
Some scientists think that the explanation for blood types may lie in their variation. That's because different blood types may protect us from different diseases.
Doctors first began to notice a link between blood types and different diseases in the middle of the 20th century, and the list has continued to grow. From Greenwell, I learn to my displeasure that blood type A puts me at a higher risk of several types of cancer, such as some forms of pancreatic cancer and leukaemia.
I'm also more prone to smallpox infections, heart disease and severe malaria. On the other hand, people with other blood types have to face increased risks of other disorders. People with type O, for example, are more likely to get ulcers and ruptured Achilles tendons. These links between blood types and diseases have a mysterious arbitrariness about them, and scientists have only begun to work out the reasons behind some of them. For example, Kevin Kain, of the University of Toronto, and his colleagues have been investigating why people with type O are better protected against severe malaria than people with other blood types.
His studies indicate that immune cells have an easier job of recognising infected blood cells if they're type O rather than other blood types. As is often the case with a big summer blockbuster, The Dark Knight Rises has its very own novelization that not only tells the whole story of the movie, but offers some new perspectives on events through some side characters that don't always get their due in the movie.
The Dark Knight Rises adaptation is on sale today from Titan Books, and to celebrate, we've got your exclusive look at the first chapter -- the introduction of Bane!
If you haven't seen the movie or watched the IMAX prologue way back in December in front of Mission Impossible: Ghost Protocol , then obviously there are spoilers here. YES NO. Was this article informative? I have no idea what it's saying.
It's muffled and garbled — vote in our poll below for what you think it sounds like. And therein lies the problem. No one knows what the hell he's saying. It's all shwords from here on out. Bane rises and says mwah wah wah wah wah, and someone pulls off his hood. Gillen looks at Bane's face mask and asks, "If I pull that off, would it be painful? Gillen asks if Bane's plan was just to get caught, and Bane responds that the second part of his plan is to crash this aircraft.
Then, out of nowhere, an even bigger plane zooms in on top of the CIA jet. And oh shit, you just know this has all been a big Bane set up. I mean you don't really know — because you can't understand a word he says, but it's pretty obvious that Bane was in control from the beginning. Gillen realizes he's been set up, but there's really nothing he can do.
People are already jumping out of the giant Bane plane and attaching lines onto the smaller CIA plane. Within minutes, the giant plane has flipped the whole CIA ship and ripped the wings off like a fly.
All that remains is the passenger tube, which flails about clinging onto Bane's bigger plane by the previously mentioned wires. Bane wants the Doctor back, but first he needs to find out exactly what the CIA learned from the scientist. The character is a policeman who, like Bruce Wayne, was an orphan, and uses this experience to deduce that Batman is in fact Bruce Wayne. However, while Blake is obviously correct, it still takes a logical leap to come to that conclusion.
As every math teacher has ever said, he has to show his work. The main message from the Dark Knight Trilogy was always that Batman was a symbol. As such, Batman could be anyone. So, the question is, how long with John Blake last as Batman? The movie ends with one of the tensest scenes in the whole trilogy.
Batman is flying the nuclear bomb out of the city using his Batplane. The audience, and the characters in the movie, are led to believe that Batman has sacrificed himself for Gotham City.
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