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Why We Have Different Blood Types
How did human blood types evolve to what they are today? Some scientists believe it was our first defense against disease.
I still remember when my mother told me I had O- blood. She said it meant I was a universal donor—anyone could receive my blood, but I could only take O- blood in return. I'll admit feeling prideful of this distinction—as if I've been selected for a duty to help others. It's a fact I've never questioned until recently. After all, what's the evolutionary advantage for having such different blood types? It certainly doesn't do us any favors when receiving a transfusion of a blood not of your type could very well kill you.
Why blood types are so important
In 1900 Austrian physician Karl Landsteiner discovered there are three blood groups A, B, and O. It was a huge find and he won a Nobel Prize in Physiology or Medicine for it in 1930. A few years later researchers would discover the AB group.
What differentiates one blood group from another are its antigens. It's a coating around the red blood cell, which helps the body identify which cells are yours. So, if an A- patient were to receive a transfusion from a B+ donor, the antibodies in the patient's system would reject the transfused blood, attacking what they perceive as a foreign invader. This attack would cause the transfused blood to clot, threatening the life of the patient.
There are two main antigens that form around our red blood cells, they are known as A and B. So, if your blood type AB, then you have both the A and B antigens. Type O lacks the A and B antigens, so the antibodies of a type O patient would attack A or B blood from a transfusion. Think of antigens as a hall pass, if your blood cells have them, then they won't get any trouble from the hall monitors (antibodies).
Photo Credit: InvictaHOG/Wikipedia
The + and – symbols also have significance in blood transfusions, which pertain to another set of antigens known as Rhesus or Rh. This is another collection of 45 different antigens. But they're all produced as a single group, so you either have all of them (Rh positive) or none of them (Rh negative). So, when it comes to transfusions AB+ can take any blood, whereas O- can only accept O- blood.
How different blood types came to be
Back when humans first roamed the Earth, we weren't concerned with blood transfusions. But science has yet to explain why some groups of people are more likely to have one blood type over another.
Based on diagrams from http://anthro.palomar.edu/vary/vary_3.htm
Type A is thought of to be the most ancient. Pre-humans began with type A blood before early humanoids began to exhibit certain mutations in the form of other blood types, which might or might not have turned into survival advantages.
“So about five million years ago, this mutation pops up called group O. And around that time, and subsequently, group B developed,” Dr. Christine Cserti-Gazdewhich, a hematologist at the University of Toronto, told NPR.
One clue to how these mutations survived can be found in their unique resistance to certain diseases. A 2007 study published in the Proceedings of the National Academy of Sciences indicates cells infected with malaria don't stick well with type-B or O blood. So, those with the O or B type lived long enough to reproduce, while the type As died out.
“Infectious organisms that carry A- and B-like antigens may have indeed played a role in the somewhat different distribution of blood types worldwide,” Harvey G. Klein, chief of the department of transfusion medicine for the National Institutes of Health, explained in a post for Scientific American.
Photo Credit: MICHAEL KAPPELER/AFP/Getty Images
Natalie has been writing professionally for about 6 years. After graduating from Ithaca College with a degree in Feature Writing, she snagged a job at PCMag.com where she had the opportunity to review all the latest consumer gadgets. Since then she has become a writer for hire, freelancing for various websites. In her spare time, you may find her riding her motorcycle, reading YA novels, hiking, or playing video games. Follow her on Twitter: @nat_schumaker
How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>
Sexuality dilemmas<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>
Regulating designer babies<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>
The father of all giant sea bugs was recently discovered off the coast of Java.
- A new species of isopod with a resemblance to a certain Sith lord was just discovered.
- It is the first known giant isopod from the Indian Ocean.
- The finding extends the list of giant isopods even further.
The ocean depths are home to many creatures that some consider to be unnatural.<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzU2NzY4My9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTYxNTUwMzg0NX0.BTK3zVeXxoduyvXfsvp4QH40_9POsrgca_W5CQpjVtw/img.png?width=980" id="b6fb0" class="rm-shortcode" data-rm-shortcode-id="2739ec50d9f9a3bd0058f937b6d447ac" data-rm-shortcode-name="rebelmouse-image" data-width="1512" data-height="2224" />
What benefit does this find have for science? And is it as evil as it looks?<div class="rm-shortcode" data-media_id="7XqcvwWp" data-player_id="FvQKszTI" data-rm-shortcode-id="8506fcd195866131efb93525ae42dec4"> <div id="botr_7XqcvwWp_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/7XqcvwWp-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/7XqcvwWp-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/7XqcvwWp-FvQKszTI.js"></script> </div> <p>The discovery of a new species is always a cause for celebration in zoology. That this is the discovery of an animal that inhabits the deeps of the sea, one of the least explored areas humans can get to, is the icing on the cake.</p><p>Helen Wong of the National University of Singapore, who co-authored the species' description, explained the importance of the discovery:</p><p>"The identification of this new species is an indication of just how little we know about the oceans. There is certainly more for us to explore in terms of biodiversity in the deep sea of our region." </p><p>The animal's visual similarity to Darth Vader is a result of its compound eyes and the curious shape of its <a href="https://lkcnhm.nus.edu.sg/research/sjades2018/" target="_blank" rel="noopener noreferrer dofollow" style="">head</a>. However, given the location of its discovery, the bottom of the remote seas, it may be associated with all manner of horrifically evil Elder Things and <a href="https://en.wikipedia.org/wiki/Cthulhu" target="_blank" rel="dofollow">Great Old Ones</a>. <em></em></p>
We look back at a year ravaged by a global pandemic, economic downturn, political turmoil and the ever-worsening climate crisis.
Billions are at risk of missing out on the digital leap forward, as growing disparities challenge the social fabric.
Image: Global Risks Report 2021<h3>Widespread effects</h3><p>"The immediate human and economic costs of COVID-19 are severe," the report says. "They threaten to scale back years of progress on reducing global poverty and inequality and further damage social cohesion and global cooperation."</p><p>For those reasons, the pandemic demonstrates why infectious diseases hits the top of the impact list. Not only has COVID-19 led to widespread loss of life, it is holding back economic development in some of the poorest parts of the world, while amplifying wealth inequalities across the globe.</p><p>At the same time, there are concerns the fight against the pandemic is taking resources away from other critical health challenges - including a <a href="https://www.weforum.org/agenda/2020/09/charts-covid19-malnutrition-educaion-mental-health-children-world/" target="_blank" rel="noopener noreferrer">disruption to measles vaccination programmes</a>.</p>
A new study explains how a chaotic region just outside a black hole's event horizon might provide a virtually endless supply of energy.
- In 1969, the physicist Roger Penrose first proposed a way in which it might be possible to extract energy from a black hole.
- A new study builds upon similar ideas to describe how chaotic magnetic activity in the ergosphere of a black hole may produce vast amounts of energy, which could potentially be harvested.
- The findings suggest that, in the very distant future, it may be possible for a civilization to survive by harnessing the energy of a black hole rather than a star.
The ergosphere<p>The ergosphere is a region just outside a black hole's event horizon, the boundary of a black hole beyond which nothing, not even light, can escape. But light and matter just outside the event horizon, in the ergosphere, would also be affected by the immense gravity of the black hole. Objects in this zone would spin in the same direction as the black hole at incredibly fast speeds, similar to objects floating around the center of a whirlpool.</p><p>The Penrose process states, in simple terms, that an object could enter the ergosphere and break into two pieces. One piece would head toward the event horizon, swallowed by the black hole. But if the other piece managed to escape the ergosphere, it could emerge with more energy than it entered with.</p><p>The movie "Interstellar" provides an example of the Penrose process. Facing a fuel shortage on a deep-space mission, the crew makes a last-ditch effort to return home by entering the ergosphere of a blackhole, ditching part of their spacecraft, and "slingshotting" away from the black hole with vast amounts of energy.</p><p>In a recent study published in the American Physical Society's <a href="https://journals.aps.org/prd/abstract/10.1103/PhysRevD.103.023014" target="_blank" style="">Physical Review D</a><em>, </em>physicists Luca Comisso and Felipe A. Asenjo used similar ideas to describe another way energy could be extracted from a black hole. The idea centers on the magnetic fields of black holes.</p><p style="margin-left: 20px;">"Black holes are commonly surrounded by a hot 'soup' of plasma particles that carry a magnetic field," Comisso, a research scientist at Columbia University and lead study author, told <a href="https://news.columbia.edu/energy-particles-magnetic-fields-black-holes" target="_blank" rel="noopener noreferrer">Columbia News</a>.</p>
Event Horizon Telescope Collaboration<p>While there might not be immediate applications for the theory, it could help scientists better understand and observe black holes. On an abstract level, the findings may expand the limits of what scientists imagine is possible in deep space.</p><p style="margin-left: 20px;">"Thousands or millions of years from now, humanity might be able to survive around a black hole without harnessing energy from stars," Comisso said. "It is essentially a technological problem. If we look at the physics, there is nothing that prevents it."</p>
A popular and longstanding wave of thought in psychology and psychotherapy is that diagnosis is not relevant for practitioners in those fields.